IPAC2013 - List of Keywords (lattice)

Paper	Title	Other Keywords	Page
MOPEA003	Status and Very First Commissioning of the ASTRID2 Synchrotron Light Source	vacuum, quadrupole, cavity, booster	64
	S.P. Møller, N. Hertel, J.S. Nielsen ISA, Aarhus, Denmark
	ASTRID2 is the new 10 nm UV and soft x-ray light source at Aarhus University. It will replace the ageing source ASTRID, which will be used as the full-energy (580 MeV) booster for ASTRID2. An upgrade of the beamlines at ASTRID are presentlytaking place before being transferred to ASTRID2 until the end of 2013. In addition new beamlines and insertion devices are being procured. Presently, ASTRID2 commissioning is alternating with ASTRID operation to continue during 2013. Status in spring 2013 includes operation of most sub-systems resulting in top-up mode operation to 150 mA. The lattice have been qualifies although a re-alignment is planned. The poster will present experiences from the first commissioning and give the status of the project.

MOPEA007	Study of Lower Emittance Optics Using Multi-Bend-Achromat Lattice at SOLEIL	emittance, dipole, optics, quadrupole	76
	R. Nagaoka, P. Brunelle, X. Gavaldà, M. Klein, A. Loulergue, A. Nadji, L.S. Nadolski, M.-A. Tordeux SOLEIL, Gif-sur-Yvette, France
	In the framework of a future upgrade of the SOLEIL 354 m long and 2.75 GeV storage ring, a series of lattice studies has been launched to aim at reducing by an order of magnitude the current 4 nm.rad horizontal emittance. In this exercise, the main constraint imposed is to leave all the existing 24 straight sections for insertion devices untouched. In the previous study (presented at IPAC 2012), the possibility of using superbends and exploiting their longitudinal dipole field variation was pursued in lowering the emittance, finding solutions with a horizontal emittance in the sub nanometer range. In the present study, the use of MBA (Multi-Bend-Achromat) lattice is explored, which is widely recognized today as the optimal lattice in reaching an ultra-low emittance. The study aims to clarify the adaptability of the MBA and the range of attainable emittance for the SOLEIL ring, in view particularly of the short straight sections existing in half of the original DBA cells in between the dipoles. The possibility of combining the previously obtained superbend solutions with the MBA lattice is also examined.

MOPEA008	A Low-Emittance Lattice for the ESRF	sextupole, emittance, dipole, injection	79
	L. Farvacque, N. Carmignani, J. Chavanne, A. Franchi, G. Le Bec, S.M. Liuzzo, B. Nash, T.P. Perron, P. Raimondi ESRF, Grenoble, France
	In the framework of its upgrade, the ESRF is looking at a new lattice for replacing the present Double Bend Achromat structure. This new lattice must have the same length and periodicity as the present one and keep the beamline source points unchanged. We will describe our design of an 844 m long lattice based on a 7-bend achromat. It is optimized for minimising the operation costs, in particular the wall-plug power, provides a large dynamic aperture allowing off-axis injection with the present ESRF injector, and gives an horizontal emittance of less than 200 pm at 6 GeV, thus considerably improving the brilliance and transverse coherence of the ESRF.

MOPEA025	Closed Orbit Correction in the High Field Lattice of ILSF Storage Ring	storage-ring, closed-orbit, dipole, sextupole	127
	H. Ghasem IPM, Tehran, Iran E. Ahmadi, F. Saeidi ILSF, Tehran, Iran
	In the high intensity storage rings, there are many sources of errors which lead to closed orbit distortion (COD). To study effect of errors on closed orbit and to find optimum arrangement of beam position monitors (BPMs) and strength of corrector magnets, different types of expected misalignments and field errors were imposed randomly in the high field lattice of ILSF storage ring. This paper gives the results of closed orbit correction in the ILSF ring and stipulates the strength of correctors.

MOPEA047	Ramping of the Solaris Storage Ring Achromat	quadrupole, optics, dipole, sextupole	184
	A.I. Wawrzyniak, C.J. Bocchetta, D. Einfeld, R. Nietubyć Solaris, Kraków, Poland D. Einfeld MAX-lab, Lund, Sweden R. Nietubyć NCBJ, Świerk/Otwock, Poland
	Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program:POIG.02.01.00-12-213/09, The combined function magnets implemented for the MAX IV and Solaris 1.5 GeV storage ring double bend achromats (DBAs) represents a challenging task in magnetic design. The constituent magnets in the DBA block may be sensitive to saturation effects which must be accounted for, especially in the case of energy ramping, as is the case for Solaris and not for MAXIV, where injection will take place at a beam energy of 0.55-0.6 GeV. The magnetic field distribution was calculated as a function of energy in the range from 0.5 GeV up to 1.5 GeV for the gradient dipole and for the quadrupoles containing a sextupole component. Results show that for the dipole, which generates the strongest field, the relative change of quadrupole strength is lower than 4.10^-3. For the quadrupoles the sextupole component is within the relative range of less than 0.7.10-4. The impact on linear and non-linear optics at low energies has been accordingly studied. This is on-going studies and only preliminary results are presented in this paper.

MOPEA049	The First Experience of PLS-II Operation	injection, linac, storage-ring, insertion	190
	S.H. Nam, M.-H. Cho, J.Y. Huang, C.D. Park, S. Shin PAL, Pohang, Kyungbuk, Republic of Korea
	Funding: Mministry of Education, Science and Technology (MEST) of Korea One of recent major activities of the Pohang Accelerator Laboratory (PAL) in Korea has been PLS-II user operation. The PLS-II is a Korea’s only and brand new 3rd generation synchrotron radiation source that was upgraded from the 16-year-old PLS in 2011. The old PLS started user service from 1995 and shutdown on Dec. 10, 2010. The PLS-II has been open to users from March 2012 with upgraded performance. The performance parameters of the PLS-II are 5.8 nm-rad emittance, 3.0GeV beam energy, and 400mA beam current with the top-up injection. The unique feature of PLS-II will be the implementation of 20 insertion-devices in a compact double-bend-achromat storage ring of 280m-long circumference. Among 20 insertion-devices, 14 are in-vacuum undulators. The first year operation in 2012 will be successfully completed and the operational statistics will be summarized and discussed.

MOPEA056	Measuring and Improving the Momentum Acceptance and Horizontal Acceptance at MAX III	cavity, electron, vacuum, storage-ring	205
	A. Hansson, Å. Andersson, J. Breunlin, G. Skripka, E.J. Wallén MAX-lab, Lund, Sweden
	Lifetime measurements for varying horizontal scraper positions performed at different RF frequencies suggested a horizontal aperture restriction in the MAX III synchrotron light source. A combination of local orbit distortions and horizontal scraper measurements pinpointed the location of the horizontal aperture restriction to the center of the main cavity straight section. The aperture restriction was determined to be located 10.4 ± 0.3 mm from the beam center. The precise result was achieved by measurements and calculations of the Touschek lifetime as a function of the main cavity voltage. Realignment of the main cavity increased the average lattice momentum acceptance from 0.0116 ± 0.0003 to 0.0158 ± 0.0003 and the horizontal acceptance from 26 ± 2 × 10^-6 m to larger than 44 ± 2 × 10^-6 m. The increase in momentum acceptance increased the lifetime in MAX III by a factor of two.

MOPEA060	Design of Low Momentum Compaction Lattices for the TPS Storage Ring	emittance, sextupole, injection, dipole	217
	C.-C. Kuo, H.-J. Tsai NSRRC, Hsinchu, Taiwan
	The nominal bunch length is around 10 ps rms in the Taiwan Photon Source (TPS), which is currently under construction. To further reduce bunch length to a few ps rms range, low momentum compaction factor configurations (low alpha), i.e., quasi-isochronous machines, are designed. The beam dynamics issues of the TPS low alpha lattices are reported.

MOPEA066	Investigation and Test of the Possibility of Reducing the Emittance of the Diamond Storage Ring	emittance, optics, wiggler, injection	234
	B. Singh, M. Apollonio, R. Bartolini, E.C. Longhi Diamond, Oxfordshire, United Kingdom R. Bartolini, T. Pulampong JAI, Oxford, United Kingdom
	Theoretical and experimental studies have been carried out at the Diamond Light Source to assess the possibility of reducing the emittance of the existing storage ring by means of a change to the optics. The optics solutions obtained so far using a Multi Objective Genetic Algorithm (MOGA) increase the dispersion and the horizontal beta function in the straight section. While the emittance can be reduced to 2.1 nm this optics is limited by the operation of high field superconducting wiggler devices. In this report we present details of the new optics and present results of practical tests. We also compare the theoretical emittance growth due to a wiggler in a dispersive region with test results.

MOPEA067	Ultra-low Emittance Upgrade Options for Third Generation Light Sources	emittance, dipole, resonance, dynamic-aperture	237
	R. Bartolini Diamond, Oxfordshire, United Kingdom T. Pulampong JAI, Oxford, United Kingdom
	The increasing efforts in the synchrotron light sources community toward the design of a diffraction limited source at multi-keV photon energy have eventually stimulated the existing facilities to investigate possible upgrade paths to higher photon brightness and lower emittances to maintain their competitiveness within the users’ community. We present a possible option for upgrading 3rd generation light sources based on a rebiuld of the arcs with MBA cells, using diamond as an example. Emphasis is given to the AP desing issues with a view to minimal changes to the machine layout, contained cost and minimal downtime

MOPEA068	Novel Lattice Upgrade Studies for Diamond Light Source	vacuum, dipole, optics, quadrupole	240
	R. Bartolini, C.P. Bailey, M.P. Cox, N.P. Hammond, J. Kay, R.P. Walker Diamond, Oxfordshire, United Kingdom R. Bartolini, T. Pulampong JAI, Oxford, United Kingdom
	Many synchrotron radiation facilities are studying lattice upgrades in order to lower the natural emittance and hence increase the radiation brightness. At Diamond we are pursuing a novel alternative, not targeting the minimum possible emittance but instead introducing additional insertion device (ID) straights and hence increasing the capacity of the facility, while still possibly achieving a more limited reduction in emittance. The new scheme involves converting some of the DBA lattice cells into a double-DBA or DDBA, with a new ID straight between the two achromats. This then allows existing or future bending magnet ports (which in Diamond are taken from near the entrance to the second dipole of the DBA lattice) to be served by a much more powerful insertion device. We present here the design concept and preliminary lattice design, and discuss the challenging magnet, vacuum and engineering issues.

MOPEA069	Tuning of the Injector System to Match Possible Lattice Upgrades at Diamond Light Source	linac, booster, injection, storage-ring	243
	C. Christou, R. Bartolini, J. Kay Diamond, Oxfordshire, United Kingdom R. Bartolini JAI, Oxford, United Kingdom
	Studies of novel lattice upgrades for Diamond Light Source to achieve an increase in the number of insertion devices and/or a lower natural emittance are underway (as reported elsewhere at this conference). Such upgrades if carried out progressively would result in successive reductions in storage ring circumference. To maintain synchronous injection then requires the injector system to operate at various frequencies to match these changes. This paper describes the tests carried out with beam, to prove that the injector system of Linac and full energy Booster can be tuned over an extended frequency range.

MOPEA070	Operating the Diamond Light Source in Low Alpha Mode for Users	injection, factory, optics, electron	246
	I.P.S. Martin, R. Bartolini, G. Cinque, G. Rehm, C.A. Thomas Diamond, Oxfordshire, United Kingdom R. Bartolini JAI, Oxford, United Kingdom
	Since its first introduction in April 2009, the low alpha operational mode has been continually refined in order to best meet the needs of the user community. Initially the optics were used only to generate short x-ray pulses, for which a stable, low emittance, single bunch was requested, with the emphasis placed on increased bunch charge over shortest absolute pulse duration. More recently, the optics have been adapted to enhance the CSR gain in the THz region of the electromagnetic spectrum. In this paper we summarise the work carried out in order to meet these two demands.

MOPEA072	Recent Improvement of the APS Booster Synchrotron	booster, emittance, injection, synchrotron	252
	C. Yao, R. Laird, V. Sajaev, N. Sereno, H. Shang, J. Wang, S. Xu ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-ACO2-O6CH11357. The APS booster injector is a 7-GeV electron synchrotron. Several improvements have been implemented in the booster area, including the development of the 92-nm low emittance lattice, upgrading the ramp current readback ADC, and development of a new firing card for the main ramp supplies. Recently we have completed the commissioning of the low emittance lattice and it is now APS operational lattice. Combined with improvement in the optimization in the storage ring lattice and injection, we have achieved close to 100% storage ring injection efficiency. This report presents the improvements and measured beam parameters and the measured performance of the ramp control.

MOPEA074	Lattice Studies for a Potential Soft X-ray Diffraction Limited Upgrade of the ALS	emittance, brightness, scattering, injection	258
	C. Steier, J.M. Byrd, R.W. Falcone, S.D. Kevan, D. Robin, C. Sun, H. Tarawneh, W. Wan LBNL, Berkeley, California, USA
	Funding: The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The Advanced Light Source (ALS) at Berkeley Lab has seen many upgrades over the years, keeping it one of the brightest sources for soft x-rays worldwide. Recent developments in magnet technology and lattice design (multi bend achromat lattices) appear to open the door for very large further increases in brightness, particularly by reducing the horizontal emittance, even within the space constraints of the existing tunnel. Initial studies yielded candidate lattices which approach the soft x-ray diffraction limit (around 2 keV) in both planes within the ALS footprint.

MOPEA075	Completion of the Brightness Upgrade of the ALS	brightness, emittance, insertion, sextupole	261
	C. Steier, B.J. Bailey, K. Berg, A. Biocca, A.T. Black, P.W. Casey, D. Colomb, R.F. Gunion, N. Li, A. Madur, S. Marks, H. Nishimura, G.C. Pappas, K.V. Petermann, G.J. Portmann, S. Prestemon, A.W. Rawlins, D. Robin, S.L. Rossi, T. Scarvie, D. Schlueter, C. Sun, H. Tarawneh, W. Wan, E.C. Williams LBNL, Berkeley, California, USA C. Chen, J. Jin, Y.M. Wen, J. Wu, L. Yin, J.D. Zhang, Q.G. Zhou SINAP, Shanghai, People's Republic of China
	Funding: The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The Advanced Light Source (ALS) at Berkeley Lab remains one of the brightest sources for soft x-rays worldwide. A multiyear upgrade of the ALS is underway, which includes new and replacement x-ray beamlines, a replacement of many of the original insertion devices and many upgrades to the accelerator. The accelerator upgrade that affects the ALS performance most directly is the ALS brightness upgrade, which reduced the horizontal emittance from 6.3 to 2.0 nm (2.5 nm effective). Magnets for this upgrade were installed starting in 2012 followed by a transition to user operations with 2.0 nm emittance in spring 2013.

MOPEA078	Commissioning and Operation of Wiggler Switchyard System for Duke FEL and HIGS	wiggler, FEL, vacuum, storage-ring	267
	Y.K. Wu, M.D. Busch, M. Emamian, J.F. Faircloth, H. Hao, J.Y. Li, S.F. Mikhailov, V. Popov, G. Swift, P.W. Wallace, P. Wang, J. Yan FEL/Duke University, Durham, North Carolina, USA A.L. Wu USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. To enable the Duke storage ring FEL to operate in VUV with adequate gain, a major storage ring upgrade was carried out in 2012 to install two additional helical FEL wigglers with a wiggler switchyard system. Using the switchyard, a quick changeover can be made between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight section. This system preserves the linear polarization capabilities of the Duke FEL and gamma-ray beams at the High Intensity Gamma-ray Source (HIGS), while enabling VUV FEL operation with a higher gain using a longer FEL with as many as four helical wigglers. The wiggler switchyard upgrade was completed in Summer 2012, followed by a rapid and successful commissioning of the Duke storage ring, FEL system, and HIGS. In this paper, we will present the results of accelerator and light source commissioning with the wiggler switchyard. We will also present preliminary results of operating the OK-5 FEL in different configurations. With the wiggler switchyard, we are well positioned to realize the operation of a VUV FEL below 190 nm and production of Compton gamma-ray beams above 100 MeV in circular polarization.

MOPEA079	Improving Emittances in Existing Storage Rings by Defocusing Dipoles	dipole, emittance, quadrupole, optics	270
	C.E. Mayes, L. Gupta, G.H. Hoffstaetter, V.O. Kostroun, A.A. Mikhailichenko CLASSE, Ithaca, New York, USA
	Designs for ultimate storage rings typically employ two strategies to lower the emittances: 1) adding more bending magnets, and 2) using only focusing quadrupole magnets, with additional defocusing in the bending magnets. In an existing storage ring, the first strategy is precluded because the number of bends is typically fixed, but the second strategy could be used at modest expense. With the CESR storage ring as an example, we show how this is possible and propose an optics that reduces its emittance by more than a factor of 20. Furthermore, such an upgrade would could be installed incrementally without any long dark-time period.

MOPME023	ORBIT Beam Simulation Progress in the 3-GeV Rapid Cycling Synchrotron of J-PARC	simulation, injection, impedance, synchrotron	521
	P.K. Saha, H. Harada, H. Hotchi, Y. Shobuda, M. Yamamoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan J.A. Holmes ORNL, Oak Ridge, Tennessee, USA S. Kato Tohoku University, Graduate School of Science, Sendai, Japan
	We have made a numerous progress for beam simulation in the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) by using 3-D particle tracking code, ORBIT. Namely, the TEAPOT lattice file used for ORBIT tracking has been made to give exactly same results to that with SAD model used for the RCS beam commissioning. In addition, time dependent lattice functions of the injection chicane magnets and similar other time dependent lattice imperfections, which are already found to have significant influences on the beam losses in the real machine have also been successfully introduced. At present, time dependent transverse and longitudinal impedances are going to be introduced. That should prove the ORBIT code much more matured for beam simulations in synchrotrons. Latest beam simulation results illustrating these new realistic features are presented.

MOPME066	Radiation of a Charged Particle Bunch Moving along Boundary of Wire Metamaterial	radiation, vacuum, diagnostics, optics	628
	A.V. Tyukhtin, S.N. Galyamin, V.V. Vorobev Saint-Petersburg State University, Russia
	Funding: Work supported by Russian Foundation for Basic Research and the Dmitry Zimin “Dynasty” Foundation. The material under consideration represents a periodical volume structure of long parallel conductive wires. If wavelengths are much greater than periods, the structure can be described as some anisotropic medium possessing both frequency and spatial dispersion* (so-called wire metamaterial). Earlier we considered the radiation of bunches moving in boundless wire metamaterial. It has been discovered that this radiation is nondivergent, and it is perspective for diagnostics of bunches*. Now we consider the case when the bunch moves in vacuum along the boundary of the semi-infinite metamaterial perpendicularly to the wires. Analytical and numerical analysis of the problem is performed. It is shown that radiation from a point charge concentrates in some vicinity of certain planes and propagates along the wires with speed of light. Series of computations show that the radiation under consideration can be useful for determination of sizes and shape of bunch. A.V. Tyukhtin, E.G. Doilnitsina, J. Phys. D - Appl. Phys., 44, 265401 (2011). **V.V. Vorobev, A.V. Tyukhtin, Phys. Rev. Lett., 108, 184801 (2012).

MOPME076	Determination of Octupole and Sextupole Polarities in the LHC	octupole, sextupole, coupling, injection	655
	M.J. McAteer, Y.I. Levinsen, E.H. Maclean, T. Persson, P.K. Skowroński, R.J. Steinhagen, R. Tomás CERN, Geneva, Switzerland
	We report the results of measurements to verify the polarity of the LHC’s lattice focusing and defocusing octupoles (MOF and MOD), spool piece octupole correctors (MCO), arc skew sextupole correctors (MSS), and interaction region sextupoles (MCSX and MCSSX). Octupole polarities were determined by measuring the change to second order chromaticity when a magnet family was trimmed. The MSS skew sextupole corrector polarities were checked by measuring the change to chromatic coupling when a magnet family was trimmed. The polarities of the MCSSX skew sextupoles in IR 1 and the MCSX normal sextupoles in IR 5 were checked by measuring the tune shift due to a magnet trim. Comparison of measurements with model predictions indicates that the polarities of the octupoles and the IR sextupoles are correct, and the polarities of the MSS skew sextupole correctors are reversed.

MOPWO018	Cellular Automaton Simulating the Motion of the Charged Particles Beam	acceleration, controls, simulation	918
	S.N. Andrianov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia V. Ryabusha Saint Petersburg State University, Saint Petersburg, Russia
	In this research we formulate and formalize the rules for the cellular automaton that emulates the motion of the charged particles beam under the effect of Coulomb force for one-, two- and three-dimensional cases. In this research we also describe the main principles of the realization of this approach in a paralleled cluster environment.

MOPWO019	An IDE for Spin-orbit Dynamics Simulation	simulation, controls, betatron, optics	921
	A.N. Ivanov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia
	In this paper a prototype of an IDE for simulation of spin-orbit motion is described. It is based on the component software development and provides a flexible graphic user interface. One of the main parts of it is numerical methods for ordinary differential equations integration. For numerical simulation it is possible use either the matrix map algorithm or traditional step-by-step methods. This workflow allows choosing one of numerical algorithms and to provide necessary computational experiments. It is also contains both a visual designer of an accelerator lattice and additional tools for control parameters of the model. There is also exists possibility for code generation in different programming languages and computation on high-performance systems.

MOPWO021	Data Management and Analysis for Beam Dynamics Simulation	simulation, EPICS, quadrupole, site	927
	D. Zyuzin FZJ, Jülich, Germany S.N. Andrianov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia
	Computer simulation of modern accelerator system is based on a number of specialized computer codes. Complexity of concerned processes and interpretation of simulation results requires comfortable and effective tools to design accelerator structure and beam characteristics, carry out computer experiments, process and visualize data. This paper proposes a prototype system with web-interface which allows the full research cycle: from lattice generation to data visualization. This approach represents a valuable tool for beam physicist providing methods to benchmark simulation engines as well as providing additional instruments for understanding physical processes in accelerator. The corresponding tools were used in application to the spin-orbit motion problems in electrostatic accelerators.

MOPWO027	Improved TEAPOT Method and Tracking with Thick Quadrupoles for the LHC and its Upgrade	quadrupole, optics, insertion, multipole	945
	H. Burkhardt, R. De Maria, M. Giovannozzi, T. Risselada CERN, Geneva, Switzerland
	The comparison between tracking with thick and thin lens models for the LHC have been studied. A widely-used method to generate thin models is based on the TEAPOT slicing, which, in the original implementation is limited in the number of slices. In this paper an improved method is presented, which overcomes some of the limitations of the original TEAPOT. The performance is analysed and the impact on numerical simulation of the dynamic aperture is evaluated, both for the LHC and its upgrade, HL-LHC.

MOPWO058	Injection Simulations for TPS Storage Ring	injection, storage-ring, simulation, kicker	1022
	C.C. Chiang, P.J. Chou NSRRC, Hsinchu, Taiwan
	We present injection simulations for the TPS (Taiwan Photon Source) storage ring. The baseline lattice of TPS storage ring is a 6-fold structure with 24 double bend cells. For the Step I commissioning, only baseline lattice with dummy chambers are installed. The three double mini-beta-y lattice with insertion devices will be applied during Step II commissioning. The Tracy-2 program is used to simulate the particle motion in 6-D phase space. We adopt lattice models which include errors of alignments and magnet fields. The particle loss due to scraping by chamber limit is recorded in Tracy-2 simulation. We can estimate the radiation distribution of a ring and provide a reference for the shielding design accordingly.

MOPWO059	Development of MATLAB-based Application Programs for the Optics Matching, Beam Steering, and Injection Conditioning in TPS Commissioning	linac, optics, injection, electron	1025
	M.-S. Chiu, H.-P. Chang, P.J. Chou, F.H. Tseng NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) is a third generation 3GeV synchrotron light source. Its first beam commissioning is scheduled in 2014. Intensive efforts are devoted to achieve efficient transportation of the first beam from the LINAC, passing through the LTB transfer line, and its injection into the booster ring. After the beam energy has been ramped up to 3GeV in booster, the beam is extracted to the BTS transfer line. At the end of BTS, the beam is injected into the storage ring and circulates around the storage ring. In order to achieve efficient beam transportation, we have developed various MATLAB-based commissioning tools for the optics matching of transfer lines, beam steering and injection conditioning of booster and storage ring.

TUODB102	Intrabeam Scattering Studies for Low Emittance of BAPS	emittance, wiggler, damping, storage-ring	1123
	S.K. Tian, Y. Jiao, J.Q. Wang, G. Xu IHEP, Beijing, People's Republic of China
	In modern storage ring light sources, intra-beam scattering (IBS) is often thought of as a fundamental limitation to achieving ultra-low emittance and hence higher brightness. Beijing Advanced Photon Source (BAPS) is under design at Institute of High Energy Physics (IHEP) which aims to emittance less than 1nm at 5GeV. To improve the coherence and high brightness, low emittance- in both transverse planes at the diffraction limit for the range of x-ray wavelengths(≈10 pm)- is being pursued. Thus, due to the very low emittance, intra-beam scattering effect is an issue. Accurate estimation to check if the design goal can be reached is necessary. In this paper, we use the 6-D accelerator simulation code-elegant and Accelerator Toolbox (AT)-a collection of tools to model storage rings in the MATLAB environment. Based on a temporary design lattice of BAPS, we present the results of particle simulation study of intra-beam scattering effect versus the beam energy, the emittance coupling factor, the bunch length, the bunch current and so on. We also studied the mitigating method by adopting damping wigglers in one or more dispersion-free regions.
	Slides TUODB102 [2.338 MB]

TUOAB203	ESRF Upgrade Phase II	emittance, storage-ring, vacuum, brilliance	1140
	J.-L. Revol, P. Berkvens, J.C. Biasci, J-F. B. Bouteille, N. Carmignani, F. Ewald, L. Farvacque, A. Franchi, L. Goirand, M. Hahn, L. Hardy, J. Jacob, J.M. Koch, G. Lebec, S.M. Liuzzo, B. Nash, T.P. Perron, E. Plouviez, P. Raimondi, K.B. Scheidt, V. Serrière ESRF, Grenoble, France
	Four years after the launch of the Upgrade Programme, the ESRF is midway through its first phase (2009-2015) and has defined the objectives for the ensuing second phase. The first phase paved the way to a new generation of nano-beam X-ray beamlines fed by an X-ray source itself substantially improved in terms of reliability, stability and brilliance. The second phase envisions a major upgrade of the source to best serve the science case of this new generation of beamlines. In December 2012, the ESRF Council endorsed Management's proposal to launch the technical design study of a new 7-bend achromat lattice. This new configuration will allow the ESRF storage ring to operate with a decrease in horizontal emittance by a factor of about 30 and a consequent increase in brilliance and coherence of the photon beam. The increase will be substantially higher at X-ray energies larger than 50 keV.
	Slides TUOAB203 [3.664 MB]

TUPEA001	Generation of Anomalous Intensive Transition Radiation for FEL	electron, radiation, dipole, polarization	1161
	K.B. Oganesyan, A.S. Gevorkyan, E.M. Sarkisyan ANSL, Yerevan, Armenia Y. Rostovtsev University of North Texas, Denton, Texas, USA
	The 3D spin-glass system in the external standing electromagnetic field is considered. It is shown on an example of amorphous quartz, under the influence of a standing microwave field, at its certain parameters, superlattice is created in the medium where difference in values of dielectric constants of neighboring layers can be up to third order. Note that this superlattice exists during the nanosecond however it is sufficient for using it as a radiator for generation of transition radiation by relativistic electrons.

TUPEA068	Wake-field Reduction in Hybrid Photonic Crystal Accelerator Cavities	wakefield, cavity, dipole, simulation	1289
	D. A. Rehn Colorado University at Boulder, Boulder, Colorado, USA C.A. Bauer, J.R. Cary, G.R. Werner CIPS, Boulder, Colorado, USA J.R. Cary, C.D. Zhou Tech-X, Boulder, Colorado, USA
	Funding: This work is supported by the U.S. Dept. of Energy, grant DE-FG02-04ER41317. Photonic crystals (PhCs) have attractive properties for manipulating electromagnetic radiation. In one application, PhCs are composed of a number of dielectric rods that can be arranged to make an accelerator cavity. These structures trap an accelerating mode and allow higher order modes to propagate out. Previous work showed that PhC structures allow excitation of unwanted transverse wake-fields that can disrupt the beam and limit luminosity levels. This work focuses on optimizing PhC cavities to reduce transverse wake-fields by minimizing the Q-factor of unwanted modes, while keeping the Q-factor of the accelerating mode high. The transverse wake-fields in the new optimized structures are compared with previously optimized structures and the CLIC cavity with HOM damping.

TUPEA085	Optics Tuning and Compensation in LCLS-II	quadrupole, undulator, focusing, optics	1313
	Y. Nosochkov, T.O. Raubenheimer, M. Woodley SLAC, Menlo Park, California, USA
	Funding: Work supported by the US Department of Energy contract DE-AC02-76SF00515. The LCLS-II is a future upgrade of the Linear Coherent Light Source (LCLS) at SLAC. It will include two new Free Electron Lasers (FELs) to generate soft and hard X-ray radiation. The 2.9 km LCLS-II lattice will include 1/3 of the SLC linac located just before the existing LCLS, the 1.2 km bypass line, the bend section, the beam separation and diagnostic regions, and the FEL undulators and dump. The LCLS operation showed that occasionally the beam phase space may be significantly mismatched due to various errors in the beamline. This requires correction to ensure good beam quality in the undulators. Similarly, the LCLS-II must have lattice correction system with a large tuning range to cancel such errors. Since the various LCLS-II regions are connected using matching sections, the latter naturally can be used for correction of the mismatched lattice functions. In addition, the large tuning capability is required to provide a wide range of focusing conditions at the FEL undulators. The compensation and tuning abilities of the LCLS-II lattice have been studied for incoming beam errors equivalent to 160% of beta beat and for a factor of 5 in the range of undulator quadrupole strengths.

TUPFI016	Optimization of Triplet Quadrupoles Field Quality for the LHC High Luminosity Lattice at Collision Energy	target, quadrupole, dynamic-aperture, luminosity	1364
	Y. Nosochkov, Y. Cai, M.-H. Wang SLAC, Menlo Park, California, USA R. De Maria, S.D. Fartoukh, M. Giovannozzi, E. McIntosh CERN, Geneva, Switzerland
	Funding: Work supported by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404; and by the US DOE contract DE-AC02-76SF00515. For the high luminosity upgrade of the LHC (HL-LHC), the beta functions at two interaction points (IP) will be significantly reduced compared to the nominal LHC lattice. This will result in much higher peak beta functions in the inner triplet (IT) quadrupoles adjacent to these IPs. The consequences are a larger beam size in these quadrupoles, higher IT chromaticity, and stronger effects of the IT field errors on dynamic aperture (DA). The IT chromaticity will be compensated using the Achromatic Telescopic Squeezing scheme. The increased IT beam size will be accommodated by installing large aperture Nb3Sn superconducting quadrupoles with 150 mm coil diameter. The field error tolerances in these magnets must satisfy the required acceptable DA while being reasonably close to realistically achievable field quality. Evaluation of the IT field errors was performed for the LHC upgrade layout version SLHCV3.01 with IT gradient of 123 T/m and IP collision beta functions of 15 cm in both planes. Dynamic aperture calculations were performed using SixTrack. Details of the optimization of the IT field errors are presented along with corrections to achieve the field quality specifications. S. Fartoukh, “An Achromatic Telescopic Squeezing (ATS) Scheme for LHC Upgrade’’, in proceedings of IPAC11, p. 2088.

TUPFI017	Evaluation of Field Quality for Separation Dipoles and Matching Section Quadrupoles for the LHC High Luminosity Lattice at Collision Energy	quadrupole, dipole, simulation, dynamic-aperture	1367
	Y. Nosochkov, Y. Cai, M.-H. Wang SLAC, Menlo Park, California, USA R. De Maria, S.D. Fartoukh, M. Giovannozzi, E. McIntosh CERN, Geneva, Switzerland
	Funding: Work supported by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404; and by the US DOE contract DE-AC02-76SF00515. The high luminosity upgrade of the LHC (HL-LHC) lattice requires new larger aperture magnets to be installed in the low-beta interaction regions (IRs). These include Nb3Sn superconducting (SC) triplet quadrupoles, Nb-Ti SC separation dipoles D1 and D2, and SC Q4 quadrupoles. The upgrade significantly reduces the beta functions at these IRs, producing higher beta functions and larger beam size in these magnets, and requiring a larger aperture. The high beta functions also increase the impact of high order field errors in these new magnets on dynamic aperture (DA). Therefore, to maintain an acceptable DA, new specifications for the magnet field quality are required. Since the IR error effects at collision are dominated by the triplets, their field quality has been studied and specified first. As a next step, the field errors were added to the D1 and D2 dipoles and Q4 quadrupoles while maintaining the triplet errors to specifications. The impact of the errors on DA has been determined in long term tracking simulations using SixTrack. The optimized field error specifications for the D1, D2 and Q4 magnets are presented. Y. Nosochkov, Y. Cai, M-H. Wang, S. Fartoukh, M. Giovannozzi, R. de Maria, E. McIntosh, “Optimization of Triplet Field Quality for the LHC High Luminosity Lattice at Collision Energy”, IPAC 2013.

TUPFI019	Magnet Misalignment Studies for the Front-end of the Neutrino Factory	target, simulation, proton, factory	1373
	G. Prior, I. Efthymiopoulos CERN, Geneva, Switzerland D.V. Neuffer, P. Snopok Fermilab, Batavia, USA C.T. Rogers STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom D. Stratakis BNL, Upton, Long Island, New York, USA
	In the Neutrino Factory Front-End the muon beam coming from the interaction of a high-power (4 MW) proton beam on a mercury jet target, is transformed through a buncher, a phase rotator and an ionization cooling channel before entering the downstream acceleration system. The muon Front-End channel is densely packed with solenoid magnets, normal conducting radio-frequency cavities and absorber windows (for the cooling section). The tolerance to the misalignment of the different components has to be determined in order on one hand to set the limits beyond which the performance of the Front-End channel would be degraded; on the other hand to optimize the design and assembly of the Front-End cells such that the component alignment can be checked and corrected for where crucial for the performance of the channel. In this paper we will show the results of the simulations of the Front-End channel performance where different components such as magnets, cavities have been randomly shifted or rotated. Detailed simulations have been done in G4BeamLine. T. J. Roberts et al. G4BeamLine 2.06 (2010) http://g4beamline.muonsinc.com/

TUPFI023	Optics Design and Lattice Optimisation for the HL-LHC	optics, luminosity, quadrupole, cavity	1385
	B.J. Holzer, R. De Maria, S.D. Fartoukh CERN, Geneva, Switzerland R. Appleby, S. Kelly, M.B. Thomas, L.N.S. Thompson UMAN, Manchester, United Kingdom A.V. Bogomyagkov BINP SB RAS, Novosibirsk, Russia A. Chancé CEA, Gif-sur-Yvette, France B. Dalena CEA/IRFU, Gif-sur-Yvette, France A. Faus-Golfe, J. Resta IFIC, Valencia, Spain K.M. Hock, M. Korostelev, L.N.S. Thompson, A. Wolski Cockcroft Institute, Warrington, Cheshire, United Kingdom C. Milardi INFN/LNF, Frascati (Roma), Italy J. Payet CEA/DSM/IRFU, France A. Wolski The University of Liverpool, Liverpool, United Kingdom
	Funding: The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Cap. Spec. Progr, Grant Agreement 284404. The luminosity upgrade project of the LHC collider at CERN is based on a strong focusing scheme to reach smallest beam sizes at the collision points. Depending on the available magnet technology (Nb3Sn or NbTi) a number of beam optics has been developed to define the specifications for the new super conducting quadrupoles. In the context of the optics matching new issues have been addressed and new concepts have been used: Quadrupole strength flexibility and chromatic corrections have been studied, as well as the influence of quadrupole fringe fields. The lattice has been optimised including the needs of the foreseen crab cavities and the transition between injection and low β optics had to guarantee smooth gradient changes over a wide range of β* values. Tolerances on misalignments and power converter ripple have been re-evaluated. Finally the combination of the quadrupole strengths in the high luminosity matching sections with those in the neighboring sectors is explained, a key concept of the ATS to reach smallest β* values. This paper presents the results obtained within the HiLumi collaboration Task 2.2 and summarises the main parameters of the project.

TUPFI035	Head-on and Long range Beam-beam Interactions in the LHC: Effective Tune Spread and Beam Stability due to Landau Damping	octupole, damping, luminosity, feedback	1421
	X. Buffat EPFL, Lausanne, Switzerland W. Herr, N. Mounet, E. Métral, T. Pieloni CERN, Geneva, Switzerland
	We discuss the Landau damping of coherent instabilities in the presence of betatron tune spread. This tune spread can originate from dedicated non-linear magnets such as octupoles, or through the beam-beam interaction. In the latter case we have to distinguish the contribution from head-on and parasitic beam-beam interactions and the collision pattern of different bunches plays an important role. The interplay of these sources of tune spread and the resulting stability is discussed for the case of the LHC.

TUPFI077	Commissioning Progress of the RHIC Electron Lenses	electron, solenoid, proton, controls	1526
	W. Fischer, Z. Altinbas, M. Anerella, M. Blaskiewicz, D. Bruno, W.C. Dawson, D.M. Gassner, X. Gu, R.C. Gupta, K. Hamdi, J. Hock, L.T. Hoff, R.L. Hulsart, A.K. Jain, P.N. Joshi, R.F. Lambiase, Y. Luo, M. Mapes, A. Marone, R.J. Michnoff, T.A. Miller, M.G. Minty, C. Montag, J.F. Muratore, S. Nemesure, D. Phillips, A.I. Pikin, S.R. Plate, P.J. Rosas, L. Snydstrup, Y. Tan, C. Theisen, P. Thieberger, J.E. Tuozzolo, P. Wanderer, S.M. White, W. Zhang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy. In polarized proton operation, the RHIC performance is limited by the head-on beam-beam effect. To overcome these limitations two electron lenses were installed and are under commissioning. One lens uses a newly manufactured superconducting solenoid, in the other lens the spare superconducting solenoid of the BNL Electron Beam Ion Source is installed to allow for propagation of the electron beam. (This spare magnet will be replaced by the same type of superconducting magnet that is also used in the other lens during the 2013 shut-down.) We give an overview of the commissioning configuration of both lenses, and report on first results in commissioning the hardware and electron beam. We also report on lattice modifications needed to adjust the phase advance between the beam-beam interactions and the electron lenses, as well as upgrades to the proton instrumentation for the commissioning.

TUPFI083	Simulation Study of Head-on Beam-beam Compensation with Realistic RHIC Lattices	dynamic-aperture, proton, resonance, simulation	1541
	Y. Luo, M. Bai, W. Fischer, C. Montag, V.H. Ranjbar, S. Tepikian BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. We performed numerical simulations to study the effects of head-on beam-beam compensation with the realistic RHIC lattices. To better cancel the beam-beam resonance driving terms during half beam-beam compensation operation, the betatron phase advances between the interaction point IP8 and the center of the electron lens should be multiples of pi. for this purpose two shunt power supplies were added to the main quadrupole circuit buses in the arc between them. For the realistic beam-beam compensation lattices, the integer tunes are (27, 29) for the Blue ring and (29, 30) for the Yellow ring. The betatron phase advances between IP8 and the e-lens are (8pi,11pi) in the Blue ring and (11pi, 9pi) in the Yellow ring. Recent simulation results will be presented.

TUPFI084	RHIC Polarized Proton Operation for 2013	emittance, polarization, injection, resonance	1544
	V.H. Ranjbar, L. A. Ahrens, E.C. Aschenauer, M. Bai, J. Beebe-Wang, M. Blaskiewicz, J.M. Brennan, K.A. Brown, D. Bruno, R. Connolly, T. D'Ottavio, K.A. Drees, Y. Dutheil, W. Fischer, C.J. Gardner, J.W. Glenn, X. Gu, M. Harvey, T. Hayes, H. Huang, R.L. Hulsart, A.I. Kirleis, J.S. Laster, C. Liu, Y. Luo, Y. Makdisi, G.J. Marr, A. Marusic, F. Méot, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, S. Nemesure, P.H. Pile, A. Poblaguev, V. Ptitsyn, G. Robert-Demolaize, T. Roser, W.B. Schmidke, V. Schoefer, F. Severino, T.C. Shrey, D. Smirnov, K.S. Smith, D. Steski, S. Tepikian, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, M. Wilinski, K. Yip, A. Zaltsman, A. Zelenski, K. Zeno, S.Y. Zhang BNL, Upton, Long Island, New York, USA O. Eyser UCR, Riverside, California, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The 2013 operation of the Relativistic Heavy Ion Collider (RHIC) marks the second year of running under the RHIC II era. Additionally this year saw the implementation of several important upgrades designed to push the intensity frontier. Two new E-lenses have been installed, along with a new lattice designed for the E-lens operation. A new polarized proton source which generates about factor of 2 more intensity was commissioned as well as a host of RF upgrades from a new longitudinal damper, Landau cavity in RHIC to a new low level RF and new harmonic structure for the AGS. We present an overview of the challenges and results from this years run.

TUPFI086	A Tapered Six Dimensional Cooling Lattice for a Muon Collider	emittance, collider, simulation, focusing	1547
	D. Stratakis, R.C. Fernow, R.B. Palmer BNL, Upton, Long Island, New York, USA
	Designs for Neutrino Factories and Muon Colliders use ionization cooling to reduce the emittance of the muon beam prior to acceleration. Two lattices based on the original RFOFO ring design representing different configurations of the magnetic field are considered. One is with a flip magnetic field and one with a non-flip magnetic field configuration that is used to eliminate for possible space-charge effects. The details of the G4Beamline tracking studies of both channels are presented and compared to the independent ICOOL code.

TUPFI087	Alternative Muon Cooling Options based on Particle-Matter-Interaction for a Neutrino Factory	cavity, focusing, solenoid, proton	1550
	D. Stratakis BNL, Upton, Long Island, New York, USA A. Alekou CERN, Geneva, Switzerland D.V. Neuffer, P. Snopok Fermilab, Batavia, USA J. Pasternak STFC/RAL, Chilton, Didcot, Oxon, United Kingdom J. Pasternak Imperial College of Science and Technology, Department of Physics, London, United Kingdom C.T. Rogers STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom P. Snopok Illinois Institute of Technology, Chicago, Illinois, USA
	Funding: This work is funded by US Dept. of Energy grant numbers DE AC02-98CH10886 An ionization cooling channel is a tightly spaced lattice containing absorbers for reducing the momentum of the muon beam, rf cavities for restoring the momentum and strong solenoids for focusing the beam. Such a lattice is an essential feature of most designs for Neutrino Factories and Muon Colliders. Here, we explore three different approaches for designing ionization cooling channels with periodic solenoidal focusing. Key parameters such as the engineering constraints that are arising from the length and separation between the solenoidal coils are systematically examined. In addition, we propose novel approaches for reducing the peak magnetic field inside the rf cavities by using either a magnetic shield system or a bucked coils configuration. Our lattice designs are numerically examined against two independent codes: The ICOOL and G4BL code. The feasibility of our proposed cooling channels to muon accelerators is examined by applying the proposed lattices to the front-end of a Neutrino Factory.

TUPFI088	Space-charge Studies for Ionization Cooling Lattices	emittance, space-charge, collider, simulation	1553
	D. Stratakis, R.B. Palmer BNL, Upton, Long Island, New York, USA D.P. Grote LLNL, Livermore, California, USA
	Funding: This work is funded by US Dept. of Energy grant numbers DE AC02-98CH10886 Intense muon beams provide a promising solution to a variety of applications ranging from nanotechnology to nuclear detections systems and from medical sciences to high energy physics. Production of such intense beam requires the beam to be cooled and ionization cooling via particle matter interaction is considered one of the most practical methods. Here a theoretical and numerical study on space-charge effects on such ionization cooling channels is presented. We show that space-charge can strongly affect the design of muon cooling systems by limiting their minimum cooling rate. Space-charge compensation solutions are discussed and the minimum cooling emittance as a function of the beam charge and pulse width is identified.

TUPME002	Design Integration at the International Linear Collider	positron, electron, damping, civil-engineering	1559
	B. List, L. Hagge, J. Kreutzkamp, N.J. Walker DESY, Hamburg, Germany
	In preparation for the Technical Design Report of the International Linear Collider, a comprehensive design of the accelerator has been compiled. DESY has contributed a systematic design integration approach, which helps to achieve a complete, correct and consistent design. We use the lattice as the leading element for design integration. Geometry information including 3D visualization models are derived from the lattice, and are used to ensure that the beamlines fit and suited for access and installation. The 3D models are also used as basis for tunnel and cavern layout. As detailed designs of components become available, the lattice is adjusted and the overall models are iterated. Lists of components are derived from the lattice and are used to generate a component bill of materials, which in turn serves as basis for cost estimation and installation planning. An integrated 3D model of the entire accelerator and all the civil construction elements helps to optimize the design for example with regard to space efficiency, ease of access for installation, and life safety. Setting up design integration in an early project stage results in a better design helps to reduce costs.

TUPME007	Beam Lifetime in Low Emittance Rings	scattering, simulation, background, factory	1574
	M. Boscolo INFN/LNF, Frascati (Roma), Italy
	In this paper I will review the main effects in low emittance rings that determine the beam lifetime by causing beam losses along the ring. As an example, the case for a B-factory based on the crab-waist collision scheme has been studied. During the machine design all the effects that determine the beam lifetime and induce backgrounds in the detector have been analyzed in details. The crab-waist scheme provides an higher luminosity, but at the same time it induces higher beam losses at the final focus. For this reason single beam effects such as Touschek and beam-gas scattering have been studied in details, by means of a macroparticle tracking code developed for this purpose. Also Radiative Bhabha scattering, that is the dominant effect to lifetime and backgrounds has been studied with the same technique to check possible multiturn losses at IR. An efficient collimation system has been designed to intercept scattered particles that would be lost in the IR in both the horizontal and the vertical plane. Recently, the Touschek tracking simulation code has been implemented to study the lifetime behavior for extremely low-emittance rings. M. Boscolo and P. Raimondi, “Monte Carlo simulation for the Touschek effect with the crab-waist scheme”, Phys. Rev. ST-AB 15 104201 (2012)

TUPME016	Crosstalk Between Beam-beam Interaction and Lattice Nonlinearities in the SuperKEKB	simulation, luminosity, resonance, betatron	1601
	D. Zhou, K. Ohmi, Y. Ohnishi, K. Oide, H. Sugimoto KEK, Ibaraki, Japan
	Momentum-dependent lattice nonlinearities have been proven to be important for the luminosity performance in the KEKB B-factory. As an upgrade of KEKB, the SuperKEKB adopts nano-beam scheme, in which the colliding beams are squeezed to extremely small sizes at the interaction point. Consequently, the lattice nonlinearities in SuperKEKB become more stronger than in KEKB. Using two codes, SAD and BBWS, we did various simulations to study the crosstalk between beam-beam interaction and lattice nonlinearities. It is found that lattice nonlinearities can cause remarkable luminosity loss in the SuperKEKB.

TUPME022	Study on the Single Bunch Transverse Emittance Growth in BAPS	emittance, wakefield, vacuum, wiggler	1619
	J. Gao, D. Wang IHEP, Beijing, People's Republic of China
	Funding: Supported by the National Foundation of Natural Sciences Contract 11175192. Beijing Advanced photon Source (BAPS) is a proposed next synchrotron radiation facility which has much smaller transverse emittance after SSRF in China, with 5 GeV energy and 1.5 km circumference. In order to explore how small the transverse emittance we can get on BAPS, this paper studies the single bunch transverse emittance growth due to short range wakefield according to J. Gao’ theory. The mechanism of wakefield induced single bunch emittance is explained first and then the transverse emittance at the design beam current is estimated. Also, the tolerances for the transverse loss factor and the vacuum chamber misalignment (or the closed orbit distortion) are presented.

TUPME055	Strawman Optics Design for the CERN LHeC ERL Test Facility	linac, optics, emittance, electron	1694
	A. Valloni, O.S. Brüning, R. Calaga, E. Jensen, M. Klein, R. Tomás, F. Zimmermann CERN, Geneva, Switzerland S.A. Bogacz, D. Douglas JLAB, Newport News, Virginia, USA
	In preparation for a future Large Hadron electron Collider (LHeC) at CERN, an ERL test facility is foreseen as a test bed for SRF development, cryogenics, and advanced beam instrumentation, as well as for studies of ERL-specific beam dynamics. The CERN ERL test facility would comprise two linacs, each consisting of 4 superconducting 5-cell cavities at 802 MHz, and two return arcs on either side. With an RF voltage of 75 MeV per linac a final electron energy of about 300 MeV is reached. The average beam current should be above 6 mA to explore the parameter range of the future LHeC. In this paper we present a preliminary optics layout.

TUPME064	Envelope Perturbations in a Space-Charge-Dominated Electron Beam	simulation, resonance, space-charge, quadrupole	1712
	W.D. Stem, B.L. Beaudoin, I. Haber, R.A. Kishek, T.W. Koeth UMD, College Park, Maryland, USA
	Funding: Supported by the US Dept. of Energy, Office of High Energy Physics, and by the US Dept. of Defense, Office of Naval Research and the Joint Technology Office. Linear perturbation analysis of the RMS envelope equations predicts a frequency splitting of the transverse envelope resonances with the onset of space charge. These resonances are a potential source of beam degradation for space-charge-dominated particle accelerators and storage rings. We use WARP for both envelope code integration and particle-in-cell (PIC) simulations to predict the behavior of these resonances for an existing alternating gradient lattice storage ring. The focus of these simulations is tailored toward examining physics that is scalable to future high-intensity accelerators. This paper provides detailed simulation results and a design for an experimental demonstration at the University of Maryland Electron Ring (UMER), a high intensity 10 keV electron storage ring.

TUPME065	Experimental Study of Horizontal-Longitudinal Coupling at CesrTA	coupling, cavity, simulation, scattering	1715
	M. P. Ehrlichman, A. Chatterjee, W. Hartung, D.P. Peterson, N.T. Rider, D. L. Rubin, J.P. Shanks, S. Wang CLASSE, Ithaca, New York, USA
	Funding: This research was supported by NSF and DOE contracts PHY-0734867, PHY-1002467, PHYS-1068662, DE-FC02-08ER41538, DE-SC0006505. In storage rings, the presence of horizontal dispersion in the RF cavities introduces x-z coupling. The result is that the beam is skewed in the horizontal-longitudinal plane. The skew angle is proportional to the V15 term of the 6X6 coupling matrix which is proportional to the RF cavity voltage and the horizontal dispersion in the cavity. Here we report experiments at CesrTA where x-z coupling was explored using three distinct lattice configurations with different V15 coupling terms. We explore x-z coupling for each of these lattices by measuring the horizontal projection of the beam with a beam size monitor, as the RF voltage is varied. The first lattice has about 1 m dispersion in the RF cavities, resulting in a V15 term at the beam size monitor source point corresponding to 16 mrad x-z tilt. In the second, the V15 generated in one pair of cavities is compensated at the second pair by adjusting the horizontal betatron phase advance between the cavity pairs. In the third, the optics are adjusted so that the RF cavity region is dispersion-free, eliminating the coupling entirely. Additionally, intra-beam scattering is evident in our measurements of beam size vs. RF voltage.

TUPWA020	The Implementation of Equipartitioning in the Proton Linac Code PADSC	emittance, space-charge, quadrupole, linac	1766
	Y.L. Zhao, S. Fu, Z. Li IHEP, Beijing, People's Republic of China
	The high intensity accelerator projects place extremely stringent requirements on particle loss, since even very small losses can lead to unacceptably high levels of radioactivity that can hinder or prevent hands-on maintenance. Such losses are known to be associated with emittance growth and beam halo. Non-equipartitioning contributes a lot for emittance growth and beam halo. The present equipartitioning realization has assumed that the emittance and space charge force are keeping constant, which will induce errors. The implementation in the proton linac code PADSC does equipartitioning optimization according to the real space charge force and emittance in the quasi period lattice.

TUPWA045	Longitudinal Space Charge Effects in the CLIC Drive Beam	space-charge, simulation, quadrupole, luminosity	1811
	R.L. Lillestøl, S. Döbert, A. Latina, D. Schulte CERN, Geneva, Switzerland E. Adli, K.N. Sjobak University of Oslo, Oslo, Norway
	The CLIC main beam is accelerated by rf power generated from a high-intensity, low-energy electron drive beam. The accelerating fields are produced in Power Extraction and Transfer Structures, and are strongly dependent on the drive beam bunch distribution, as well as other parameters. We investigate how longitudinal space charge affects the bunch distribution and the corresponding power production, and discuss how the bunch length evolution can affect the main beam. We also describe the development of a Particle-in-Cell space charge solver which was used for the study.

TUPWA046	Experimental Results from the Test Beam Line in the CLIC Test Facility 3	emittance, simulation, quadrupole, extraction	1814
	R.L. Lillestøl, S. Döbert, M. Olvegård CERN, Geneva, Switzerland E. Adli University of Oslo, Oslo, Norway
	In the CLIC two-beam scheme, the main beam is accelerated by rf power provided by energy extraction from a secondary drive beam. This energy is extracted in decelerators, and the first prototype decelerator is the Test Beam Line in the CLIC Test Facility 3. The line is currently equipped with 12 Power Extraction and Transfer Structures (PETS), which allows for extracting up to 40% of the beam energy. We correlate the measured deceleration with predictions from the beam current and the rf power produced in the PETS. We also discuss recent bunch length measurements and how it influences the deceleration. Finally we look at the evolution of the transverse emittance.

TUPWA057	Effects of Transient CSR Wakefields on Microbunching in a Bunch Compressor	wakefield, impedance, radiation, FEL	1832
	C.E. Mitchell, J. Qiang LBNL, Berkeley, California, USA
	Funding: Supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The standard analytical model of CSR-induced microbunching in a bunch compressor chicane makes use of a steady-state 1-D model of the longitudinal CSR interaction. This model is numerically generalized to include the effects of transient CSR wakefields due to bend entry and exit, as well as CSR that is generated in upstream bends and propagates across one or more lattice elements before interacting with the beam. The resulting linear integral equation for CSR-induced microbunching is solved numerically for the second bunch compressor of a proposed Next Generation Light Source.

TUPWO001	A New 5BA Low Emittance Lattice for Sirius	emittance, dipole, sextupole, coupling	1874
	L. Liu, N. Milas, A.H.C. Mukai, X.R. Resende, A.R.D. Rodrigues, F. H. de Sá LNLS, Campinas, Brazil
	Sirius is a third-generation low emittance synchrotron light source under construction at LNLS, the Brazilian Synchrotron Light Laboratory. A new 5BA lattice was designed in replacement for the previous TBA lattice with the aim to reduce the emittance to sub-nm.rad values. The new design has a circumference of 518 m with 20 achromatic straight sections and a natural emittance of 0.28 nm.rad at 3 GeV for the bare lattice (without IDs). The dipoles combine low 0.58 T field magnets for the main beam deflection with a 2 T short superbend magnet sandwiched in the center dipole. This creates a longitudinal dipole gradient that is used both to lower the emittance and to provide hard X-ray dipole sources.

TUPWO003	CLIC 3 TeV Beam Size Optimization with Radiation Effects	radiation, quadrupole, dipole, photon	1877
	O.R. Blanco, P. Bambade LAL, Orsay, France R. Tomás CERN, Geneva, Switzerland
	Horizontal beamsize contribution due to radiation on bending magnets is calculated using theoretical results and recent improvements in mapclass (Mapclass2). In order to verify the code and validity of its approximations, a simple lattice with no geometrical nor chromatic aberrations, one dipole and a final drift has been used to compare Mapclass2 calculations and Placet tracking results. CLIC 3TeV lattice is optimized including the radiation effects. Current results show that correction of chromatic aberrations impose constraints in radiation improvement.

TUPWO005	Survey of Beam Optics Solutions for the MLS Lattice	optics, emittance, quadrupole, cavity	1883
	M. Ries, J. Feikes, T. Goetsch, G. Wüstefeld HZB, Berlin, Germany
	The Metrology Light Source (MLS) is an electron storage ring containing 24 quadrupole magnets which can be powered individually. Fully exploring the capabilities of the machine optics by tracking or experiment would be very time consuming. Therefore the quadrupoles were combined in five families and a numerical brute force approach was used to scan for areas of stable solutions in the scope of linear beam optics. In order to get information on the expected beam lifetimes for each generated optics, a model for the Touschek lifetime was implemented. Simulation results as well as experimental tests of selected optics will be presented.

TUPWO015	Off-Energy Injection Into Newsubaru	injection, septum, synchrotron, betatron	1913
	Y. Shoji LASTI, Hyogo, Japan Y. Minagawa, Y. Takemura JASRI/SPring-8, Hyogo-ken, Japan
	NewSUBARU is temporarily operated in non-achromatic mode for the research using chromaticity modulation. At this special mode, a normal injection scheme does not work because of the larger stored beam size and smaller ring acceptance. In order to obtain good injection efficiency, which enables top-up operation, the injected beam energy is displaced from the ring energy. The finite dispersion of 1.1 m at the injection point and the energy displacement of 0.7% reduce the betatron oscillation amplitude of the injected beam. A trade off is a synchrotron oscillation produced by the energy mismatch. Using this technique, it became possible to inject new beam using a closed fast injection bump and also a top-up operation. Although it is not possible to inject beam to a normal achromatic lattice using a closed bump. Especially in non-achromatic quasi-isochronous ring, it would be possible that the energy mismatch is reduced by the betatron amplitude dependent shift of the equilibrium energy.

TUPWO022	Space Charge Effects Study and Optimization in CSNS/LRBT	space-charge, emittance, linac, injection	1928
	Z.P. Li, N. Huang, W.B. Liu, S. Wang IHEP, Beijing, People's Republic of China
	The linac to ring beam transport line (LRBT) of China Spallation Neutron Source (CSNS) connecting the linac and the rapid cycling synchrotron (RCS) transports 80 MeV negative hydrogen ions (H⁻) beams for RCS injection. Space charge effect in LRBT is significant due to small emittance and high current density of the beam, which is a major cause of emittance growth and beam loss. An achromatic transverse optical matching was performed by TRACE 3D code. Emittance growths of beams with different initial distributions in different LRBT lattices were studied separately. Simulation results show that the LRBT design with triplet can mitigate the emittance growth by lattice optimization of the front matching section and no beam loss occurs at 15mA. The location and parameters of the debuncher in LRBT were also optimized to reduce the momentum spread and energy jitter.

TUPWO033	Effects Estimation of Superconducting Wiggler in SSRF	emittance, dynamic-aperture, optics, quadrupole	1946
	Q.L. Zhang, B.C. Jiang, S.Q. Tian, W.Z. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	Superconducting wiggler (SW) may greatly impact on the beam dynamics in a storage ring. The effects of a 4.5T SW has been studied in SSRF including impaction on the emittance and the energy spread. To keep an undegraded storage ring performance, a local achromatic lattice is considered. The combat between the damping effect of the SW and emittance growth of local achromatic lattice is the main concern of this paper. Other effects (tune shift, beta beating, dynamics aperture, etc.) with the SW are also simulated and optimized in this paper.

TUPWO035	Physical Design of Beam Transport Line of a Compact Terahertz FEL	undulator, quadrupole, electron, FEL	1952
	H. Zeng, Q.S. Chen, Q. Fu, B. Qin, B. Wu, Y.Q. Xiong HUST, Wuhan, People's Republic of China G. Feng, Y.J. Pei USTC/NSRL, Hefei, Anhui, People's Republic of China
	The single pass, linac-based compact terahertz source at HUST is now in the physical design stage. To match Twiss parameters and dispersion function of the electron beam at the undulator entrance and get smaller beta function in the whole line, several lattices based on the double bending achromat(DBA) structure were discussed and the optimized design is given with beam dynamics results–calculated by MAD and Trace 3D.

TUPWO042	Modeling Results from Magnetic and Beam Based Measurements of the ALBA Gradient Dipoles	dipole, focusing, quadrupole, storage-ring	1967
	X. Gavaldà SOLEIL, Gif-sur-Yvette, France G. Benedetti, J. Marcos, Z. Martí CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The ALBA lattice is a DBA-like structure where most of vertical focusing is provided by gradient dipoles. In the first year of machine operation, the model parameters describing the focusing strength of the 32 dipoles have been calibrated by fitting the measured closed orbit response matrix. The mean k-value obtained from this analysis differs by -0.3% with respect to the value taken from the magnetic measurements previous to the magnet installation, while the k variation within the 32 dipoles is of the same order of magnitude. The optics results (tunes, beta beating, dispersion) obtained with the beam based model are compared with the predicted ones from the magnetic measurement model.

TUPWO063	Reducing HLS-II Emittance by Radiation Damping Partition Factor Exchange	wiggler, emittance, storage-ring, damping	2009
	J.Y. Li FEL/Duke University, Durham, North Carolina, USA W. Li, G. Liu, W. Xu USTC/NSRL, Hefei, Anhui, People's Republic of China Y. Li BNL, Upton, Long Island, New York, USA
	Funding: The Introduction of Outstanding Technological Talents Program of Chinese Academy of Sciences, 2010. In this paper, we present a preliminary study on using a Robinson wiggler, a wiggler with transverse gradient, to reduce the horizontal beam emittance of the Hefei Light Source II (HLS-II) storage ring. A proof-of-principle study demonstrates that it is possible to further reduce the horizontal beam emittance by 50\% using a 2-meter long Robinson wiggler installed on a dispersive straight section. This encouraging result suggests a feasible option to significantly improve the HLS-II performance at a relative low cost and without significant modification to its global configuration in the near future.

TUPWO069	Optimization of FACET Optics	sextupole, optics, chromatic-effects, simulation	2024
	M.-H. Wang, F.-J. Decker, N. Lipkowitz, Y. Nosochkov, G.R. White, U. Wienands, M. Woodley, G. Yocky SLAC, Menlo Park, California, USA
	Funding: supported by the US Department of Energy contract DE-AC02-76SF00515. The FACET accelerator facility is designed to provide short and intense e^- or e⁺ bunches with small spot size for plasma wakefield accelerator research and other experiments. It is based on the SLAC linac with a compressor chicane in sector-10, and a second compressor chicane and final focus in sector-20 (S20). Originally, the S20 chicane was designed to be compatible with an upgrade to include a second S20 chicane for simultaneous transport of e^- and e⁺ bunches. This placed additional optics constraints which lead to strong focusing in the S20 chicane. The latter increases the effects of errors causing emittance growth. Lately, it has been decided not to proceed with the upgrade option. Therefore, there is a potential for improving the optics by relaxing the constraints. In this study, we explore alternative optics designs where beta functions in the S20 chicane and final focus are reduced in order to minimize the error effects. The optics and non-linear aberrations are evaluated, and the chromatic correction is optimized for each design. Beam tracking simulations are performed using Elegant and Lucretia. The most optimal designs are identified based on these simulations.

WEPWA060	The Kharkov X-ray Generator Facility NESTOR	storage-ring, electron, controls, injection	2253
	A.A. Shcherbakov, V.P. Androsov, N. Ayzatsky, V.N. Boriskin, E.V. Bulyak, A.N. Dovbnya, P. Gladkikh, A.N. Gordienko, V.A. Grevtsev, A. Gvozd, V.E. Ivashchenko, A.A. Kalamayko, I.I. Karnaukhov, I.M. Karnaukhov, V.P. Kozin, V.A. Kushnir, V.P. Lyashchenko, V.S. Margin, N.I. Mocheshnikov, V.V. Mytrochenko, A. Mytsykov, I.M. Neklyudov, T.F. Nikitina, F.A. Peev, O.V. Ryezayev, V.L. Skirda, V.A. Skomorokhov, Y.N. Telegin, V.I. Trotsenko, A.Y. Zelinsky, O.D. Zvonarjova NSC/KIPT, Kharkov, Ukraine J.I.M. Botman TUE, Eindhoven, The Netherlands I.V. Drebot LAL, Orsay, France
	The last few years the sources of the X-rays NESTOR based on a storage ring with low beam energy and Compton scattering of intense laser beam are under design and development in NSC KIPT. The main task of the project is to develop compact intense X-ray generator on the base of relatively cheap accelerator equipment and up-to-date laser technologies. The paper is devoted to description of the last results on construction and commissioning of the facility.

WEPWO004	Studies of Systematic Flux Expulsion in Superconducting Niobium	niobium, cavity, simulation, controls	2316
	J.M. Vogt, J. Knobloch, O. Kugeler HZB, Berlin, Germany
	The quality factor Q0 that can be obtained in a superconducting cavity is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We believe that cooling conditions have an additional impact, as they appear to influence the amount of trapped flux and hence the residual resistance. We have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach Tc from below in the superconducting state. Although the sample remains in the superconducting state, a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Furthermore, simulations using the Radia software package for Mathematica developed by the ESR were used to better unterstand the measured changes in magnetic flux around the Sample. Applying a similar procedure for minimization of trapped magnetic flux to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q0.

WEPEA008	Influence of Higher Order Phase Slip Factor Contributions on Beam Loss during SIS-100 Proton Operation	quadrupole, sextupole, simulation, dynamic-aperture	2507
	S. Sorge, O. Boine-Frankenheim, G. Franchetti GSI, Darmstadt, Germany
	The projected FAIR synchrotron SIS-100 is envisaged to accelerate intense proton and heavy-ion beams. The maximum proton energy will be E=29 GeV. In order to stay below transition energy a special powering scheme of the quadrupoles has been introduced which provides a maximum transition gamma of 45.5. The resulting settings of the quadrupole focusing strengths generate large maxima of the horizontal beta and dispersion functions. In particle tracking simulation we observed beam loss caused by a large momentum spread in the deformed rf bucket close to transition. Application of the chromaticity correction sextupoles led to a reduction of the first-order phase slip factor term and of the beam losses. In this contribution we will analyze the effect of the sextupoles on the higher-order components of the phase slip factor. The rf bucket shape will be discussed as well as the transverse beam loss and possible longitudinal instabilities.

WEPEA012	Study of Laser Wakefield Accelerators as Injectors for Synchrotron Light Sources	laser, synchrotron, simulation, storage-ring	2519
	S. Hillenbrand, V. Judin, A.-S. Müller KIT, Karlsruhe, Germany R.W. Aßmann, S. Hillenbrand CERN, Geneva, Switzerland O. Jansen, A.M. Pukhov HHUD, Dusseldorf, Germany
	Short bunch lengths, high beam energies, and small facility footprint make Laser Wakefield Accelerators (LWFA) very interesting as injectors for Synchrotron Light Sources. In this paper, we describe exemplary investigations for the ANKA storage ring.

WEPEA022	Analytical Estimations of the Dynamic Apertures of Beams with Momentum Deviation and Application in FFAG	dynamic-aperture, sextupole, positron, simulation	2546
	M. Xiao, J. Gao IHEP, Beijing, People's Republic of China
	Analytical formulae for estimating the dynamic apertures of synchrotron particles has been well established. Based on the standard mapping, we extend the analytical formulae of dynamic aperture for off-momentum particles in circular accelerator. And we compare the analytical results with the simulation ones in the BEPC-II positron ring lattice under some conditions. What's more, we give the analytical formulae of dynamic aperture for FFAG in the similar way.

WEPEA023	Space Charge Effects for Different CSNS/RCS Working Points	resonance, simulation, space-charge, emittance	2549
	S.Y. Xu, N. Wang, S. Wang IHEP, Beijing, People's Republic of China
	The China Spallation Neutron Source (CSNS) operates at 25 Hz repetition rate with the design beam power of 100 KW. CSNS consists of an 80-MeV linac and a 1.6-GeV Rapid Cycling Synchrotron (RCS). Due to the high beam density and high repetition rate for CSNS/RCS, the rate of beam loss must be controlled to a very low level. The major source of beam loss is associated with resonances. Thus, choosing he best suitable working points on the tune diagram is important to reach low beam loss. Different tune areas are explored and compared by considering resonances and the effects of space charge, which can drive particles into the excited resonances. Different working points are simulated and compared by using the codes ORBIT and SIMPSONS.

WEPEA025	Chromatic Sextupole Pair Optimization Methods for Enlarging Dynamic Aperture	sextupole, dynamic-aperture, focusing, storage-ring	2555
	Z. Bai, Q.K. Jia, W. Li, L. Wang, Q. Zhang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Based on the step-by-step chromaticity compensation method [1] and artificial intelligence algorithms, we propose new numerical methods, called chromatic sextupole pair optimization methods, for enlarging the dynamic aperture of electron storage rings. In the new methods, the decision variables related to chromatic sextupole pairs are optimized using artificial intelligence algorithms to enlarge the dynamic aperture. We demonstrate that the new methods are equivalent to the recently used numerical method, in which the decision variables, sextupole strengths, are optimized using artificial intelligence algorithms. [1] E. Levichev, P. Piminov, Proceedings of EPAC 2006, p. 2116.

WEPEA029	The SHER-HIAF Ring Lattice Design	injection, quadrupole, ion, kicker	2561
	X. Gao, W.P. Chai, G.D. Shen, J. Shi, J.W. Xia, J.C. Yang IMP, Lanzhou, People's Republic of China
	Super Heavy Experimental Ring (SHER) is one of the rings of the next accelerator complex High Intensity Heavy Ion Accelerator Facility (HIAF) at IMP[4]. Here, present ideas of the lattice design for the operation of the large acceptance ring are presented. The SHER ring has to be optimized for e-cooling and the lattice is designed for different modes. First of all, it is designed in the so called isochronous mode as time-of-flight mass spectrometer for short-lived secondary nuclei. Secondly, SHER can also be used to be a storage ring for collecting and cooling the secondary rare isotope beams from the transport line. In order to fulfill it's purpose, the ion optics can be set to different ion optical modes

WEPEA037	Testing of Symplectic Integrator of Spin-orbit Motion Based on Matrix Formalism	simulation, storage-ring, electromagnetic-fields	2582
	A.N. Ivanov, S.N. Andrianov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia R. Maier, Y. Senichev, D. Zyuzin FZJ, Jülich, Germany
	Investigation of spin-orbital motion in electromagnetic fields requires different numerical methods. Approaches for long-term evolution modelling need both performance and symplecticity. In this paper we discuss matrix maps method for numerical simulation. We examine symplectification and accuracy in terms of electostatic storage ring. The results are compared with traditional symplectic step-by-step methods.

WEPEA050	Analysis of Possible Functional Forms of the Scaling Law for Dynamic Aperture as a Function of Time	dynamic-aperture, luminosity, beam-losses, simulation	2618
	M. Giovannozzi, R. De Maria, F. Lang CERN, Geneva, Switzerland
	Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404. In recent studies, the evolution of the dynamic aperture with time has been fitted with a simple scaling law based on a limited number of free parameters. In this paper, different approaches to improve the numerical stability of the fit are presented, together with a new functional form. The results are discussed in details and applied to a set of numerical simulations for the LHC.

WEPME056	Application of Z-transform to Noise Response Modeling of a Bunch-by-bunch Feedback System	feedback, storage-ring, pick-up, monitoring	3058
	C. Yao, N.P. Di Monte, A.J. Scaminaci, H. Shang ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-ACO2-O6CH11357. The APS storage ring has an electron beam energy of 7 GeV and a single current of up to 16 mA. Transverse beam instability is corrected by a combination of chromatic correction and bunch-by-bunch feedback system. Noises produced in the pickup circuits is processed and transferred to the beam the same as a beam signal, which contributes to beam motion when the loops are closed. By analyzing the input data stream of the feedback system, one can passively obtain useful information, such as the tunes, loop stability, noise spectrum, etc. This approach has been reported by J. Klute and D. Teytelman. We implemented a passive and continuous tune monitoring process at the APS storage ring. In order to understand the underlying principle, we applied z-transform analysis to the noise-response model of a bunch-by-bunch feedback system. Our analysis shows a clear relationship between the spectrum of the noise response and the open-loop response of the beam. The noise-response model can also be applied to other areas, such as stability and noise analysis of a bunch-by-bunch feedback system. This report presents our analysis and some experimental data.

THYB101	Suppressing Transverse Beam Halo with Nonlinear Magnetic Fields	resonance, space-charge, damping, octupole	3099
	S.D. Webb, D.T. Abell, D.L. Bruhwiler, J.R. Cary Tech-X, Boulder, Colorado, USA V.V. Danilov ORNL, Oak Ridge, Tennessee, USA S. Nagaitsev, A. Valishev Fermilab, Batavia, USA
	Funding: This work was supported in part by the US Department of Energy's Office of Science, Office of High Energy Physics, under grant No. DE-SC0006247. Traditional space charge driven resonances, such as beam halo, arise due to the underlying linear nature of accelerator lattices. In this talk, we present initial results on a new class of intrinsically nonlinear lattices, which introduce a large tune spread naturally. The resulting nonlinear decoherence suppresses the onset of beam halo.
	Slides THYB101 [63.510 MB]

THOBB102	Beam Coupling Impedance Localization Technique Validation and Measurements in the CERN Machines	impedance, kicker, quadrupole, betatron	3106
	N. Biancacci, G. Arduini, T. Argyropoulos, H. Bartosik, R. Calaga, K. Cornelis, S.S. Gilardoni, N. Mounet, E. Métral, Y. Papaphilippou, S. Persichelli, G. Rumolo, B. Salvant, G. Sterbini, R. Tomás, R. Wasef CERN, Geneva, Switzerland M. Migliorati, L. Palumbo URLS, Rome, Italy
	The beam coupling impedance could lead to limitations in beam brightness and quality, and therefore it needs accurate quantification and continuous monitoring in order to detect and mitigate high impedance sources. In the CERN machines, for example, kickers and collimators are expected to be the main contributors to the total imaginary part of the transverse impedance. In order to detect the other sources, a beam based measurement was developed: from the variation of betatron phase beating with intensity, it is possible to detect the locations of main impedance sources. In this work we present the application of the method with beam measurements in the CERN PS, SPS and LHC.
	Slides THOBB102 [7.224 MB]

THPPA02	Features and Applications of the Program ELEGANT	simulation, electron, linac, FEL	3139
	M. Borland ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357. ELEGANT is an open-source accelerator design and simulation code that has been in use and development for nearly two decades. In that time, it has evolved into a fairly general code for the design and modeling of linacs and storage rings, due in no small measure to suggestions and feedback from users world-wide. The code is best known for modeling of linacs for free electron lasers and particularly its relatively fast and straightforward modeling of coherent synchrotron radiation in magnetic bunch compression systems. This capability led to the discovery of a microbunching instability in such systems, thus helping to seed a new field of research. ELEGANT's capabilities are enhanced by the use of self-describing data files and the Self-Describing Data Sets (SDDS) toolkit. In this paper, we briefly review the features and capabilities of the code, then give a series of application examples from simulation of linear accelerators and storage rings.
	Slides THPPA02 [0.477 MB]

THPEA057	Compensation Schemes for Operation of FEL Wigglers on Duke Storage Ring	wiggler, FEL, storage-ring, quadrupole	3270
	J.Y. Li, H. Hao, S.F. Mikhailov, V. Popov, W. Wu, Y.K. Wu FEL/Duke University, Durham, North Carolina, USA
	Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. The Duke FEL is the photon driver for the High Intensity Gamma-ray Source (HIGS). To extend the capabilities of the FEL and HIGS to higher photon energy regions, a FEL wiggler switchyard system was developed in the recent years. This system was installed and commissioned in 2012. The FEL wiggler switchyard is used to change between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight section in a short period of time (a few days). With a total of six electromagnetic wigglers, the Duke FEL can be operated in a number of wiggler configurations and with a wide range of magnetic fields. The operation of uncompensated FEL wigglers can cause significant changes to the electron beam closed orbit and magnetic lattice. To maintain a sufficiently large dynamic aperture for an efficient injection and good beam lifetime, a set of complex compensation schemes, including magnetic field and lattice compensation, have been developed for the operation of the FEL wigglers. This paper reports the overall architecture and performance of the FEL wiggler compensation schemes and their implementation in the accelerator controls system using the feedforward mechanism.

THPEA059	Database for Accelerator Modeling	controls, simulation, monitoring, extraction	3273
	C.P. Chu, J. Wu SLAC, Menlo Park, California, USA D. Dohan, G. Shen BNL, Upton, Long Island, New York, USA H.H. Lv IHEP, Beijing, People's Republic of China Y. Zhang FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661. A database for model data is design for the Facility for Rare Isotope Beams (FRIB) Project. The database schema design takes most general approach and is not limited to FRIB models. Programmatically access to the database can be done through a set of Application Programming Interfaces (APIs). Initial data population demonstrates that the database is suitable for XAL application framework. The model database is also part of a collaboration for complete database needs among various domains across an accelerator.

THPWO027	Lattice and Error Studies for J-PARC Linac Upgrade to 50mA/400MeV	emittance, linac, simulation, focusing	3818
	Y. Liu KEK/JAEA, Ibaraki-Ken, Japan M. Ikegami J-PARC, KEK & JAEA, Ibaraki-ken, Japan
	Equi-partitioning (EP) setting is applied as base-line design for the J-PARC linac upgrade from present 15mA/181MeVto 50mA/400MeV H⁻ beam. We also studied the possibility of mitigating the intra-beam stripping (IBSt) with constant-envelop setting for the frequency jump from 324MHz to the 972MHz ACS section. Since the constant-envelop setting here for the frequency jump is away from equi-partitioning and close to the resonances kz=3kx, kz=2kx and so on, considerable emittance exchange and mismatch were found in the simulation. It is natural to continue the work to explore the parameter space around the above two typical settings. Three key points are to be checked. The first is the tradeoff between the envelopes big enough to suppress the IBSt and tunes not to be too depressed to the space charge region. The second point is the sensitivity of these lattices vs. errors. The third is about the criterion of mismatch in the presence of emittance exchange. When emittance exchange is serious the mismatch can be unavoidable. So it is crucial to ensure the settings are in the safe region free from un-controlled mismatch.

THPWO090	MEBT Design for the Front End Test Stand Project at RAL	quadrupole, cavity, diagnostics, emittance	3969
	M. Aslaninejad, J.K. Pozimski, P. Savage Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	The Front End Test Stand (FETS) linear accelerator at Rutherford Appleton laboratory (RAL) will accelerate a 60 mA, 2 ms, 50 pps H⁻ beam up to 3 MeV. A new lattice design for the Medium Energy Beam Transport (MEBT) with a fast-slow chopping system is presented. Beam dynamic simulation has shown very good particle transmission in this new lattice with space charge effects included. The beam energy distribution on the beam choppers dumps is also calculated.

THPWO091	Staging Scenarios for Project-X	linac, emittance, rfq, acceleration	3972
	N. Solyak, J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A. Saini, A. Vivoli, V.P. Yakovlev Fermilab, Batavia, USA
	Funding: US DOE under contract DE-AC02-76CH03000. Project-X is a high intensity proton source in development at Fermilab. At its heart is a linac based on superconducting technology comprising two distinct sections. The first one operates in CW mode and delivers beam with a flexible time structure to simultaneous experimental programs at 1 and 3 GeV. The second one operates in pulsed mode and accelerates a modest fraction (5%) of the beam from 3 GeV to 8 GeV for accumulation in the existing Main Injector complex. In an era of constrained budgets, construction in stages -with each stage capable of supporting worthy scientific programs - may be advantageous. Requirements for each program, coupled to the physical constraints imposed by the Fermilab site have led to a few possible scenarios, which are discussed in this contribution. In particular, we examine the implications of introducing bends in the linac at 1 and 3 GeV in terms of overall performance, flexibility and cost.

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MOPEA003

Status and Very First Commissioning of the ASTRID2 Synchrotron Light Source

vacuum, quadrupole, cavity, booster

64

S.P. Møller, N. Hertel, J.S. Nielsen
ISA, Aarhus, Denmark

ASTRID2 is the new 10 nm UV and soft x-ray light source at Aarhus University. It will replace the ageing source ASTRID, which will be used as the full-energy (580 MeV) booster for ASTRID2. An upgrade of the beamlines at ASTRID are presentlytaking place before being transferred to ASTRID2 until the end of 2013. In addition new beamlines and insertion devices are being procured. Presently, ASTRID2 commissioning is alternating with ASTRID operation to continue during 2013. Status in spring 2013 includes operation of most sub-systems resulting in top-up mode operation to 150 mA. The lattice have been qualifies although a re-alignment is planned. The poster will present experiences from the first commissioning and give the status of the project.

MOPEA007

Study of Lower Emittance Optics Using Multi-Bend-Achromat Lattice at SOLEIL

emittance, dipole, optics, quadrupole

76

R. Nagaoka, P. Brunelle, X. Gavaldà, M. Klein, A. Loulergue, A. Nadji, L.S. Nadolski, M.-A. Tordeux
SOLEIL, Gif-sur-Yvette, France

In the framework of a future upgrade of the SOLEIL 354 m long and 2.75 GeV storage ring, a series of lattice studies has been launched to aim at reducing by an order of magnitude the current 4 nm.rad horizontal emittance. In this exercise, the main constraint imposed is to leave all the existing 24 straight sections for insertion devices untouched. In the previous study (presented at IPAC 2012), the possibility of using superbends and exploiting their longitudinal dipole field variation was pursued in lowering the emittance, finding solutions with a horizontal emittance in the sub nanometer range. In the present study, the use of MBA (Multi-Bend-Achromat) lattice is explored, which is widely recognized today as the optimal lattice in reaching an ultra-low emittance. The study aims to clarify the adaptability of the MBA and the range of attainable emittance for the SOLEIL ring, in view particularly of the short straight sections existing in half of the original DBA cells in between the dipoles. The possibility of combining the previously obtained superbend solutions with the MBA lattice is also examined.

MOPEA008

A Low-Emittance Lattice for the ESRF

sextupole, emittance, dipole, injection

79

L. Farvacque, N. Carmignani, J. Chavanne, A. Franchi, G. Le Bec, S.M. Liuzzo, B. Nash, T.P. Perron, P. Raimondi
ESRF, Grenoble, France

In the framework of its upgrade, the ESRF is looking at a new lattice for replacing the present Double Bend Achromat structure. This new lattice must have the same length and periodicity as the present one and keep the beamline source points unchanged. We will describe our design of an 844 m long lattice based on a 7-bend achromat. It is optimized for minimising the operation costs, in particular the wall-plug power, provides a large dynamic aperture allowing off-axis injection with the present ESRF injector, and gives an horizontal emittance of less than 200 pm at 6 GeV, thus considerably improving the brilliance and transverse coherence of the ESRF.

MOPEA025

Closed Orbit Correction in the High Field Lattice of ILSF Storage Ring

storage-ring, closed-orbit, dipole, sextupole

127

H. Ghasem
IPM, Tehran, Iran
E. Ahmadi, F. Saeidi
ILSF, Tehran, Iran

In the high intensity storage rings, there are many sources of errors which lead to closed orbit distortion (COD). To study effect of errors on closed orbit and to find optimum arrangement of beam position monitors (BPMs) and strength of corrector magnets, different types of expected misalignments and field errors were imposed randomly in the high field lattice of ILSF storage ring. This paper gives the results of closed orbit correction in the ILSF ring and stipulates the strength of correctors.

MOPEA047

Ramping of the Solaris Storage Ring Achromat

quadrupole, optics, dipole, sextupole

184

A.I. Wawrzyniak, C.J. Bocchetta, D. Einfeld, R. Nietubyć
Solaris, Kraków, Poland
D. Einfeld
MAX-lab, Lund, Sweden
R. Nietubyć
NCBJ, Świerk/Otwock, Poland

Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program:POIG.02.01.00-12-213/09,
The combined function magnets implemented for the MAX IV and Solaris 1.5 GeV storage ring double bend achromats (DBAs) represents a challenging task in magnetic design. The constituent magnets in the DBA block may be sensitive to saturation effects which must be accounted for, especially in the case of energy ramping, as is the case for Solaris and not for MAXIV, where injection will take place at a beam energy of 0.55-0.6 GeV. The magnetic field distribution was calculated as a function of energy in the range from 0.5 GeV up to 1.5 GeV for the gradient dipole and for the quadrupoles containing a sextupole component. Results show that for the dipole, which generates the strongest field, the relative change of quadrupole strength is lower than 4.10^-3. For the quadrupoles the sextupole component is within the relative range of less than 0.7.10-4. The impact on linear and non-linear optics at low energies has been accordingly studied. This is on-going studies and only preliminary results are presented in this paper.

MOPEA049

The First Experience of PLS-II Operation

injection, linac, storage-ring, insertion

190

S.H. Nam, M.-H. Cho, J.Y. Huang, C.D. Park, S. Shin
PAL, Pohang, Kyungbuk, Republic of Korea

Funding: Mministry of Education, Science and Technology (MEST) of Korea
One of recent major activities of the Pohang Accelerator Laboratory (PAL) in Korea has been PLS-II user operation. The PLS-II is a Korea’s only and brand new 3rd generation synchrotron radiation source that was upgraded from the 16-year-old PLS in 2011. The old PLS started user service from 1995 and shutdown on Dec. 10, 2010. The PLS-II has been open to users from March 2012 with upgraded performance. The performance parameters of the PLS-II are 5.8 nm-rad emittance, 3.0GeV beam energy, and 400mA beam current with the top-up injection. The unique feature of PLS-II will be the implementation of 20 insertion-devices in a compact double-bend-achromat storage ring of 280m-long circumference. Among 20 insertion-devices, 14 are in-vacuum undulators. The first year operation in 2012 will be successfully completed and the operational statistics will be summarized and discussed.

MOPEA056

Measuring and Improving the Momentum Acceptance and Horizontal Acceptance at MAX III

cavity, electron, vacuum, storage-ring

205

A. Hansson, Å. Andersson, J. Breunlin, G. Skripka, E.J. Wallén
MAX-lab, Lund, Sweden

Lifetime measurements for varying horizontal scraper positions performed at different RF frequencies suggested a horizontal aperture restriction in the MAX III synchrotron light source. A combination of local orbit distortions and horizontal scraper measurements pinpointed the location of the horizontal aperture restriction to the center of the main cavity straight section. The aperture restriction was determined to be located 10.4 ± 0.3 mm from the beam center. The precise result was achieved by measurements and calculations of the Touschek lifetime as a function of the main cavity voltage. Realignment of the main cavity increased the average lattice momentum acceptance from 0.0116 ± 0.0003 to 0.0158 ± 0.0003 and the horizontal acceptance from 26 ± 2 × 10^-6 m to larger than 44 ± 2 × 10^-6 m. The increase in momentum acceptance increased the lifetime in MAX III by a factor of two.

MOPEA060

Design of Low Momentum Compaction Lattices for the TPS Storage Ring

emittance, sextupole, injection, dipole

217

C.-C. Kuo, H.-J. Tsai
NSRRC, Hsinchu, Taiwan

The nominal bunch length is around 10 ps rms in the Taiwan Photon Source (TPS), which is currently under construction. To further reduce bunch length to a few ps rms range, low momentum compaction factor configurations (low alpha), i.e., quasi-isochronous machines, are designed. The beam dynamics issues of the TPS low alpha lattices are reported.

MOPEA066

Investigation and Test of the Possibility of Reducing the Emittance of the Diamond Storage Ring

emittance, optics, wiggler, injection

234

B. Singh, M. Apollonio, R. Bartolini, E.C. Longhi
Diamond, Oxfordshire, United Kingdom
R. Bartolini, T. Pulampong
JAI, Oxford, United Kingdom

Theoretical and experimental studies have been carried out at the Diamond Light Source to assess the possibility of reducing the emittance of the existing storage ring by means of a change to the optics. The optics solutions obtained so far using a Multi Objective Genetic Algorithm (MOGA) increase the dispersion and the horizontal beta function in the straight section. While the emittance can be reduced to 2.1 nm this optics is limited by the operation of high field superconducting wiggler devices. In this report we present details of the new optics and present results of practical tests. We also compare the theoretical emittance growth due to a wiggler in a dispersive region with test results.

MOPEA067

Ultra-low Emittance Upgrade Options for Third Generation Light Sources

emittance, dipole, resonance, dynamic-aperture

237

R. Bartolini
Diamond, Oxfordshire, United Kingdom
T. Pulampong
JAI, Oxford, United Kingdom

The increasing efforts in the synchrotron light sources community toward the design of a diffraction limited source at multi-keV photon energy have eventually stimulated the existing facilities to investigate possible upgrade paths to higher photon brightness and lower emittances to maintain their competitiveness within the users’ community. We present a possible option for upgrading 3rd generation light sources based on a rebiuld of the arcs with MBA cells, using diamond as an example. Emphasis is given to the AP desing issues with a view to minimal changes to the machine layout, contained cost and minimal downtime

MOPEA068

Novel Lattice Upgrade Studies for Diamond Light Source

vacuum, dipole, optics, quadrupole

240

R. Bartolini, C.P. Bailey, M.P. Cox, N.P. Hammond, J. Kay, R.P. Walker
Diamond, Oxfordshire, United Kingdom
R. Bartolini, T. Pulampong
JAI, Oxford, United Kingdom

Many synchrotron radiation facilities are studying lattice upgrades in order to lower the natural emittance and hence increase the radiation brightness. At Diamond we are pursuing a novel alternative, not targeting the minimum possible emittance but instead introducing additional insertion device (ID) straights and hence increasing the capacity of the facility, while still possibly achieving a more limited reduction in emittance. The new scheme involves converting some of the DBA lattice cells into a double-DBA or DDBA, with a new ID straight between the two achromats. This then allows existing or future bending magnet ports (which in Diamond are taken from near the entrance to the second dipole of the DBA lattice) to be served by a much more powerful insertion device. We present here the design concept and preliminary lattice design, and discuss the challenging magnet, vacuum and engineering issues.

MOPEA069

Tuning of the Injector System to Match Possible Lattice Upgrades at Diamond Light Source

linac, booster, injection, storage-ring

243

C. Christou, R. Bartolini, J. Kay
Diamond, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

Studies of novel lattice upgrades for Diamond Light Source to achieve an increase in the number of insertion devices and/or a lower natural emittance are underway (as reported elsewhere at this conference). Such upgrades if carried out progressively would result in successive reductions in storage ring circumference. To maintain synchronous injection then requires the injector system to operate at various frequencies to match these changes. This paper describes the tests carried out with beam, to prove that the injector system of Linac and full energy Booster can be tuned over an extended frequency range.

MOPEA070

Operating the Diamond Light Source in Low Alpha Mode for Users

injection, factory, optics, electron

246

I.P.S. Martin, R. Bartolini, G. Cinque, G. Rehm, C.A. Thomas
Diamond, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

Since its first introduction in April 2009, the low alpha operational mode has been continually refined in order to best meet the needs of the user community. Initially the optics were used only to generate short x-ray pulses, for which a stable, low emittance, single bunch was requested, with the emphasis placed on increased bunch charge over shortest absolute pulse duration. More recently, the optics have been adapted to enhance the CSR gain in the THz region of the electromagnetic spectrum. In this paper we summarise the work carried out in order to meet these two demands.

MOPEA072

Recent Improvement of the APS Booster Synchrotron

booster, emittance, injection, synchrotron

252

C. Yao, R. Laird, V. Sajaev, N. Sereno, H. Shang, J. Wang, S. Xu
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-ACO2-O6CH11357.
The APS booster injector is a 7-GeV electron synchrotron. Several improvements have been implemented in the booster area, including the development of the 92-nm low emittance lattice, upgrading the ramp current readback ADC, and development of a new firing card for the main ramp supplies. Recently we have completed the commissioning of the low emittance lattice and it is now APS operational lattice. Combined with improvement in the optimization in the storage ring lattice and injection, we have achieved close to 100% storage ring injection efficiency. This report presents the improvements and measured beam parameters and the measured performance of the ramp control.

MOPEA074

Lattice Studies for a Potential Soft X-ray Diffraction Limited Upgrade of the ALS

emittance, brightness, scattering, injection

258

C. Steier, J.M. Byrd, R.W. Falcone, S.D. Kevan, D. Robin, C. Sun, H. Tarawneh, W. Wan
LBNL, Berkeley, California, USA

Funding: The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source (ALS) at Berkeley Lab has seen many upgrades over the years, keeping it one of the brightest sources for soft x-rays worldwide. Recent developments in magnet technology and lattice design (multi bend achromat lattices) appear to open the door for very large further increases in brightness, particularly by reducing the horizontal emittance, even within the space constraints of the existing tunnel. Initial studies yielded candidate lattices which approach the soft x-ray diffraction limit (around 2 keV) in both planes within the ALS footprint.

MOPEA075

Completion of the Brightness Upgrade of the ALS

brightness, emittance, insertion, sextupole

261

C. Steier, B.J. Bailey, K. Berg, A. Biocca, A.T. Black, P.W. Casey, D. Colomb, R.F. Gunion, N. Li, A. Madur, S. Marks, H. Nishimura, G.C. Pappas, K.V. Petermann, G.J. Portmann, S. Prestemon, A.W. Rawlins, D. Robin, S.L. Rossi, T. Scarvie, D. Schlueter, C. Sun, H. Tarawneh, W. Wan, E.C. Williams
LBNL, Berkeley, California, USA
C. Chen, J. Jin, Y.M. Wen, J. Wu, L. Yin, J.D. Zhang, Q.G. Zhou
SINAP, Shanghai, People's Republic of China

Funding: The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source (ALS) at Berkeley Lab remains one of the brightest sources for soft x-rays worldwide. A multiyear upgrade of the ALS is underway, which includes new and replacement x-ray beamlines, a replacement of many of the original insertion devices and many upgrades to the accelerator. The accelerator upgrade that affects the ALS performance most directly is the ALS brightness upgrade, which reduced the horizontal emittance from 6.3 to 2.0 nm (2.5 nm effective). Magnets for this upgrade were installed starting in 2012 followed by a transition to user operations with 2.0 nm emittance in spring 2013.

MOPEA078

Commissioning and Operation of Wiggler Switchyard System for Duke FEL and HIGS

wiggler, FEL, vacuum, storage-ring

267

Y.K. Wu, M.D. Busch, M. Emamian, J.F. Faircloth, H. Hao, J.Y. Li, S.F. Mikhailov, V. Popov, G. Swift, P.W. Wallace, P. Wang, J. Yan
FEL/Duke University, Durham, North Carolina, USA
A.L. Wu
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033.
To enable the Duke storage ring FEL to operate in VUV with adequate gain, a major storage ring upgrade was carried out in 2012 to install two additional helical FEL wigglers with a wiggler switchyard system. Using the switchyard, a quick changeover can be made between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight section. This system preserves the linear polarization capabilities of the Duke FEL and gamma-ray beams at the High Intensity Gamma-ray Source (HIGS), while enabling VUV FEL operation with a higher gain using a longer FEL with as many as four helical wigglers. The wiggler switchyard upgrade was completed in Summer 2012, followed by a rapid and successful commissioning of the Duke storage ring, FEL system, and HIGS. In this paper, we will present the results of accelerator and light source commissioning with the wiggler switchyard. We will also present preliminary results of operating the OK-5 FEL in different configurations. With the wiggler switchyard, we are well positioned to realize the operation of a VUV FEL below 190 nm and production of Compton gamma-ray beams above 100 MeV in circular polarization.

MOPEA079

Improving Emittances in Existing Storage Rings by Defocusing Dipoles

dipole, emittance, quadrupole, optics

270

C.E. Mayes, L. Gupta, G.H. Hoffstaetter, V.O. Kostroun, A.A. Mikhailichenko
CLASSE, Ithaca, New York, USA

Designs for ultimate storage rings typically employ two strategies to lower the emittances: 1) adding more bending magnets, and 2) using only focusing quadrupole magnets, with additional defocusing in the bending magnets. In an existing storage ring, the first strategy is precluded because the number of bends is typically fixed, but the second strategy could be used at modest expense. With the CESR storage ring as an example, we show how this is possible and propose an optics that reduces its emittance by more than a factor of 20. Furthermore, such an upgrade would could be installed incrementally without any long dark-time period.

MOPME023

ORBIT Beam Simulation Progress in the 3-GeV Rapid Cycling Synchrotron of J-PARC

simulation, injection, impedance, synchrotron

521

P.K. Saha, H. Harada, H. Hotchi, Y. Shobuda, M. Yamamoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
J.A. Holmes
ORNL, Oak Ridge, Tennessee, USA
S. Kato
Tohoku University, Graduate School of Science, Sendai, Japan

We have made a numerous progress for beam simulation in the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) by using 3-D particle tracking code, ORBIT. Namely, the TEAPOT lattice file used for ORBIT tracking has been made to give exactly same results to that with SAD model used for the RCS beam commissioning. In addition, time dependent lattice functions of the injection chicane magnets and similar other time dependent lattice imperfections, which are already found to have significant influences on the beam losses in the real machine have also been successfully introduced. At present, time dependent transverse and longitudinal impedances are going to be introduced. That should prove the ORBIT code much more matured for beam simulations in synchrotrons. Latest beam simulation results illustrating these new realistic features are presented.

MOPME066

Radiation of a Charged Particle Bunch Moving along Boundary of Wire Metamaterial

radiation, vacuum, diagnostics, optics

628

A.V. Tyukhtin, S.N. Galyamin, V.V. Vorobev
Saint-Petersburg State University, Russia

Funding: Work supported by Russian Foundation for Basic Research and the Dmitry Zimin “Dynasty” Foundation.
The material under consideration represents a periodical volume structure of long parallel conductive wires. If wavelengths are much greater than periods, the structure can be described as some anisotropic medium possessing both frequency and spatial dispersion* (so-called wire metamaterial). Earlier we considered the radiation of bunches moving in boundless wire metamaterial. It has been discovered that this radiation is nondivergent, and it is perspective for diagnostics of bunches**. Now we consider the case when the bunch moves in vacuum along the boundary of the semi-infinite metamaterial perpendicularly to the wires. Analytical and numerical analysis of the problem is performed. It is shown that radiation from a point charge concentrates in some vicinity of certain planes and propagates along the wires with speed of light. Series of computations show that the radiation under consideration can be useful for determination of sizes and shape of bunch.
*A.V. Tyukhtin, E.G. Doilnitsina, J. Phys. D - Appl. Phys., 44, 265401 (2011).
**V.V. Vorobev, A.V. Tyukhtin, Phys. Rev. Lett., 108, 184801 (2012).

MOPME076

Determination of Octupole and Sextupole Polarities in the LHC

octupole, sextupole, coupling, injection

655

M.J. McAteer, Y.I. Levinsen, E.H. Maclean, T. Persson, P.K. Skowroński, R.J. Steinhagen, R. Tomás
CERN, Geneva, Switzerland

We report the results of measurements to verify the polarity of the LHC’s lattice focusing and defocusing octupoles (MOF and MOD), spool piece octupole correctors (MCO), arc skew sextupole correctors (MSS), and interaction region sextupoles (MCSX and MCSSX). Octupole polarities were determined by measuring the change to second order chromaticity when a magnet family was trimmed. The MSS skew sextupole corrector polarities were checked by measuring the change to chromatic coupling when a magnet family was trimmed. The polarities of the MCSSX skew sextupoles in IR 1 and the MCSX normal sextupoles in IR 5 were checked by measuring the tune shift due to a magnet trim. Comparison of measurements with model predictions indicates that the polarities of the octupoles and the IR sextupoles are correct, and the polarities of the MSS skew sextupole correctors are reversed.

MOPWO018

Cellular Automaton Simulating the Motion of the Charged Particles Beam

acceleration, controls, simulation

918

S.N. Andrianov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia
V. Ryabusha
Saint Petersburg State University, Saint Petersburg, Russia

In this research we formulate and formalize the rules for the cellular automaton that emulates the motion of the charged particles beam under the effect of Coulomb force for one-, two- and three-dimensional cases. In this research we also describe the main principles of the realization of this approach in a paralleled cluster environment.

MOPWO019

An IDE for Spin-orbit Dynamics Simulation

simulation, controls, betatron, optics

921

A.N. Ivanov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia

In this paper a prototype of an IDE for simulation of spin-orbit motion is described. It is based on the component software development and provides a flexible graphic user interface. One of the main parts of it is numerical methods for ordinary differential equations integration. For numerical simulation it is possible use either the matrix map algorithm or traditional step-by-step methods. This workflow allows choosing one of numerical algorithms and to provide necessary computational experiments. It is also contains both a visual designer of an accelerator lattice and additional tools for control parameters of the model. There is also exists possibility for code generation in different programming languages and computation on high-performance systems.

MOPWO021

Data Management and Analysis for Beam Dynamics Simulation

simulation, EPICS, quadrupole, site

927

D. Zyuzin
FZJ, Jülich, Germany
S.N. Andrianov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia

Computer simulation of modern accelerator system is based on a number of specialized computer codes. Complexity of concerned processes and interpretation of simulation results requires comfortable and effective tools to design accelerator structure and beam characteristics, carry out computer experiments, process and visualize data. This paper proposes a prototype system with web-interface which allows the full research cycle: from lattice generation to data visualization. This approach represents a valuable tool for beam physicist providing methods to benchmark simulation engines as well as providing additional instruments for understanding physical processes in accelerator. The corresponding tools were used in application to the spin-orbit motion problems in electrostatic accelerators.

MOPWO027

Improved TEAPOT Method and Tracking with Thick Quadrupoles for the LHC and its Upgrade

quadrupole, optics, insertion, multipole

945

H. Burkhardt, R. De Maria, M. Giovannozzi, T. Risselada
CERN, Geneva, Switzerland

The comparison between tracking with thick and thin lens models for the LHC have been studied. A widely-used method to generate thin models is based on the TEAPOT slicing, which, in the original implementation is limited in the number of slices. In this paper an improved method is presented, which overcomes some of the limitations of the original TEAPOT. The performance is analysed and the impact on numerical simulation of the dynamic aperture is evaluated, both for the LHC and its upgrade, HL-LHC.

MOPWO058

Injection Simulations for TPS Storage Ring

injection, storage-ring, simulation, kicker

1022

C.C. Chiang, P.J. Chou
NSRRC, Hsinchu, Taiwan

We present injection simulations for the TPS (Taiwan Photon Source) storage ring. The baseline lattice of TPS storage ring is a 6-fold structure with 24 double bend cells. For the Step I commissioning, only baseline lattice with dummy chambers are installed. The three double mini-beta-y lattice with insertion devices will be applied during Step II commissioning. The Tracy-2 program is used to simulate the particle motion in 6-D phase space. We adopt lattice models which include errors of alignments and magnet fields. The particle loss due to scraping by chamber limit is recorded in Tracy-2 simulation. We can estimate the radiation distribution of a ring and provide a reference for the shielding design accordingly.

MOPWO059

Development of MATLAB-based Application Programs for the Optics Matching, Beam Steering, and Injection Conditioning in TPS Commissioning

linac, optics, injection, electron

1025

M.-S. Chiu, H.-P. Chang, P.J. Chou, F.H. Tseng
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) is a third generation 3GeV synchrotron light source. Its first beam commissioning is scheduled in 2014. Intensive efforts are devoted to achieve efficient transportation of the first beam from the LINAC, passing through the LTB transfer line, and its injection into the booster ring. After the beam energy has been ramped up to 3GeV in booster, the beam is extracted to the BTS transfer line. At the end of BTS, the beam is injected into the storage ring and circulates around the storage ring. In order to achieve efficient beam transportation, we have developed various MATLAB-based commissioning tools for the optics matching of transfer lines, beam steering and injection conditioning of booster and storage ring.

TUODB102

Intrabeam Scattering Studies for Low Emittance of BAPS

emittance, wiggler, damping, storage-ring

1123

S.K. Tian, Y. Jiao, J.Q. Wang, G. Xu
IHEP, Beijing, People's Republic of China

In modern storage ring light sources, intra-beam scattering (IBS) is often thought of as a fundamental limitation to achieving ultra-low emittance and hence higher brightness. Beijing Advanced Photon Source (BAPS) is under design at Institute of High Energy Physics (IHEP) which aims to emittance less than 1nm at 5GeV. To improve the coherence and high brightness, low emittance- in both transverse planes at the diffraction limit for the range of x-ray wavelengths(≈10 pm)- is being pursued. Thus, due to the very low emittance, intra-beam scattering effect is an issue. Accurate estimation to check if the design goal can be reached is necessary. In this paper, we use the 6-D accelerator simulation code-elegant and Accelerator Toolbox (AT)-a collection of tools to model storage rings in the MATLAB environment. Based on a temporary design lattice of BAPS, we present the results of particle simulation study of intra-beam scattering effect versus the beam energy, the emittance coupling factor, the bunch length, the bunch current and so on. We also studied the mitigating method by adopting damping wigglers in one or more dispersion-free regions.

Slides TUODB102 [2.338 MB]

TUOAB203

ESRF Upgrade Phase II

emittance, storage-ring, vacuum, brilliance

1140

J.-L. Revol, P. Berkvens, J.C. Biasci, J-F. B. Bouteille, N. Carmignani, F. Ewald, L. Farvacque, A. Franchi, L. Goirand, M. Hahn, L. Hardy, J. Jacob, J.M. Koch, G. Lebec, S.M. Liuzzo, B. Nash, T.P. Perron, E. Plouviez, P. Raimondi, K.B. Scheidt, V. Serrière
ESRF, Grenoble, France

Four years after the launch of the Upgrade Programme, the ESRF is midway through its first phase (2009-2015) and has defined the objectives for the ensuing second phase. The first phase paved the way to a new generation of nano-beam X-ray beamlines fed by an X-ray source itself substantially improved in terms of reliability, stability and brilliance. The second phase envisions a major upgrade of the source to best serve the science case of this new generation of beamlines. In December 2012, the ESRF Council endorsed Management's proposal to launch the technical design study of a new 7-bend achromat lattice. This new configuration will allow the ESRF storage ring to operate with a decrease in horizontal emittance by a factor of about 30 and a consequent increase in brilliance and coherence of the photon beam. The increase will be substantially higher at X-ray energies larger than 50 keV.

Slides TUOAB203 [3.664 MB]

TUPEA001

Generation of Anomalous Intensive Transition Radiation for FEL

electron, radiation, dipole, polarization

1161

K.B. Oganesyan, A.S. Gevorkyan, E.M. Sarkisyan
ANSL, Yerevan, Armenia
Y. Rostovtsev
University of North Texas, Denton, Texas, USA

The 3D spin-glass system in the external standing electromagnetic field is considered. It is shown on an example of amorphous quartz, under the influence of a standing microwave field, at its certain parameters, superlattice is created in the medium where difference in values of dielectric constants of neighboring layers can be up to third order. Note that this superlattice exists during the nanosecond however it is sufficient for using it as a radiator for generation of transition radiation by relativistic electrons.

TUPEA068

Wake-field Reduction in Hybrid Photonic Crystal Accelerator Cavities

wakefield, cavity, dipole, simulation

1289

D. A. Rehn
Colorado University at Boulder, Boulder, Colorado, USA
C.A. Bauer, J.R. Cary, G.R. Werner
CIPS, Boulder, Colorado, USA
J.R. Cary, C.D. Zhou
Tech-X, Boulder, Colorado, USA

Funding: This work is supported by the U.S. Dept. of Energy, grant DE-FG02-04ER41317.
Photonic crystals (PhCs) have attractive properties for manipulating electromagnetic radiation. In one application, PhCs are composed of a number of dielectric rods that can be arranged to make an accelerator cavity. These structures trap an accelerating mode and allow higher order modes to propagate out. Previous work showed that PhC structures allow excitation of unwanted transverse wake-fields that can disrupt the beam and limit luminosity levels. This work focuses on optimizing PhC cavities to reduce transverse wake-fields by minimizing the Q-factor of unwanted modes, while keeping the Q-factor of the accelerating mode high. The transverse wake-fields in the new optimized structures are compared with previously optimized structures and the CLIC cavity with HOM damping.

TUPEA085

Optics Tuning and Compensation in LCLS-II

quadrupole, undulator, focusing, optics

1313

Y. Nosochkov, T.O. Raubenheimer, M. Woodley
SLAC, Menlo Park, California, USA

Funding: Work supported by the US Department of Energy contract DE-AC02-76SF00515.
The LCLS-II is a future upgrade of the Linear Coherent Light Source (LCLS) at SLAC. It will include two new Free Electron Lasers (FELs) to generate soft and hard X-ray radiation. The 2.9 km LCLS-II lattice will include 1/3 of the SLC linac located just before the existing LCLS, the 1.2 km bypass line, the bend section, the beam separation and diagnostic regions, and the FEL undulators and dump. The LCLS operation showed that occasionally the beam phase space may be significantly mismatched due to various errors in the beamline. This requires correction to ensure good beam quality in the undulators. Similarly, the LCLS-II must have lattice correction system with a large tuning range to cancel such errors. Since the various LCLS-II regions are connected using matching sections, the latter naturally can be used for correction of the mismatched lattice functions. In addition, the large tuning capability is required to provide a wide range of focusing conditions at the FEL undulators. The compensation and tuning abilities of the LCLS-II lattice have been studied for incoming beam errors equivalent to 160% of beta beat and for a factor of 5 in the range of undulator quadrupole strengths.

TUPFI016

Optimization of Triplet Quadrupoles Field Quality for the LHC High Luminosity Lattice at Collision Energy

target, quadrupole, dynamic-aperture, luminosity

1364

Y. Nosochkov, Y. Cai, M.-H. Wang
SLAC, Menlo Park, California, USA
R. De Maria, S.D. Fartoukh, M. Giovannozzi, E. McIntosh
CERN, Geneva, Switzerland

Funding: Work supported by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404; and by the US DOE contract DE-AC02-76SF00515.
For the high luminosity upgrade of the LHC (HL-LHC), the beta functions at two interaction points (IP) will be significantly reduced compared to the nominal LHC lattice. This will result in much higher peak beta functions in the inner triplet (IT) quadrupoles adjacent to these IPs. The consequences are a larger beam size in these quadrupoles, higher IT chromaticity, and stronger effects of the IT field errors on dynamic aperture (DA). The IT chromaticity will be compensated using the Achromatic Telescopic Squeezing scheme*. The increased IT beam size will be accommodated by installing large aperture Nb3Sn superconducting quadrupoles with 150 mm coil diameter. The field error tolerances in these magnets must satisfy the required acceptable DA while being reasonably close to realistically achievable field quality. Evaluation of the IT field errors was performed for the LHC upgrade layout version SLHCV3.01 with IT gradient of 123 T/m and IP collision beta functions of 15 cm in both planes. Dynamic aperture calculations were performed using SixTrack. Details of the optimization of the IT field errors are presented along with corrections to achieve the field quality specifications.
* S. Fartoukh, “An Achromatic Telescopic Squeezing (ATS) Scheme for LHC Upgrade’’, in proceedings of IPAC11, p. 2088.

TUPFI017

Evaluation of Field Quality for Separation Dipoles and Matching Section Quadrupoles for the LHC High Luminosity Lattice at Collision Energy

quadrupole, dipole, simulation, dynamic-aperture

1367

Y. Nosochkov, Y. Cai, M.-H. Wang
SLAC, Menlo Park, California, USA
R. De Maria, S.D. Fartoukh, M. Giovannozzi, E. McIntosh
CERN, Geneva, Switzerland

Funding: Work supported by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404; and by the US DOE contract DE-AC02-76SF00515.
The high luminosity upgrade of the LHC (HL-LHC) lattice requires new larger aperture magnets to be installed in the low-beta interaction regions (IRs). These include Nb3Sn superconducting (SC) triplet quadrupoles, Nb-Ti SC separation dipoles D1 and D2, and SC Q4 quadrupoles. The upgrade significantly reduces the beta functions at these IRs, producing higher beta functions and larger beam size in these magnets, and requiring a larger aperture. The high beta functions also increase the impact of high order field errors in these new magnets on dynamic aperture (DA). Therefore, to maintain an acceptable DA, new specifications for the magnet field quality are required. Since the IR error effects at collision are dominated by the triplets, their field quality has been studied and specified first*. As a next step, the field errors were added to the D1 and D2 dipoles and Q4 quadrupoles while maintaining the triplet errors to specifications. The impact of the errors on DA has been determined in long term tracking simulations using SixTrack. The optimized field error specifications for the D1, D2 and Q4 magnets are presented.
* Y. Nosochkov, Y. Cai, M-H. Wang, S. Fartoukh, M. Giovannozzi, R. de Maria, E. McIntosh, “Optimization of Triplet Field Quality for the LHC High Luminosity Lattice at Collision Energy”, IPAC 2013.

TUPFI019

Magnet Misalignment Studies for the Front-end of the Neutrino Factory

target, simulation, proton, factory

1373

G. Prior, I. Efthymiopoulos
CERN, Geneva, Switzerland
D.V. Neuffer, P. Snopok
Fermilab, Batavia, USA
C.T. Rogers
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
D. Stratakis
BNL, Upton, Long Island, New York, USA

In the Neutrino Factory Front-End the muon beam coming from the interaction of a high-power (4 MW) proton beam on a mercury jet target, is transformed through a buncher, a phase rotator and an ionization cooling channel before entering the downstream acceleration system. The muon Front-End channel is densely packed with solenoid magnets, normal conducting radio-frequency cavities and absorber windows (for the cooling section). The tolerance to the misalignment of the different components has to be determined in order on one hand to set the limits beyond which the performance of the Front-End channel would be degraded; on the other hand to optimize the design and assembly of the Front-End cells such that the component alignment can be checked and corrected for where crucial for the performance of the channel. In this paper we will show the results of the simulations of the Front-End channel performance where different components such as magnets, cavities have been randomly shifted or rotated. Detailed simulations have been done in G4BeamLine*. * T. J. Roberts et al. G4BeamLine 2.06 (2010) http://g4beamline.muonsinc.com/

TUPFI023

Optics Design and Lattice Optimisation for the HL-LHC

optics, luminosity, quadrupole, cavity

1385

B.J. Holzer, R. De Maria, S.D. Fartoukh
CERN, Geneva, Switzerland
R. Appleby, S. Kelly, M.B. Thomas, L.N.S. Thompson
UMAN, Manchester, United Kingdom
A.V. Bogomyagkov
BINP SB RAS, Novosibirsk, Russia
A. Chancé
CEA, Gif-sur-Yvette, France
B. Dalena
CEA/IRFU, Gif-sur-Yvette, France
A. Faus-Golfe, J. Resta
IFIC, Valencia, Spain
K.M. Hock, M. Korostelev, L.N.S. Thompson, A. Wolski
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C. Milardi
INFN/LNF, Frascati (Roma), Italy
J. Payet
CEA/DSM/IRFU, France
A. Wolski
The University of Liverpool, Liverpool, United Kingdom

Funding: The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Cap. Spec. Progr, Grant Agreement 284404.
The luminosity upgrade project of the LHC collider at CERN is based on a strong focusing scheme to reach smallest beam sizes at the collision points. Depending on the available magnet technology (Nb3Sn or NbTi) a number of beam optics has been developed to define the specifications for the new super conducting quadrupoles. In the context of the optics matching new issues have been addressed and new concepts have been used: Quadrupole strength flexibility and chromatic corrections have been studied, as well as the influence of quadrupole fringe fields. The lattice has been optimised including the needs of the foreseen crab cavities and the transition between injection and low β optics had to guarantee smooth gradient changes over a wide range of β* values. Tolerances on misalignments and power converter ripple have been re-evaluated. Finally the combination of the quadrupole strengths in the high luminosity matching sections with those in the neighboring sectors is explained, a key concept of the ATS to reach smallest β* values. This paper presents the results obtained within the HiLumi collaboration Task 2.2 and summarises the main parameters of the project.

TUPFI035

Head-on and Long range Beam-beam Interactions in the LHC: Effective Tune Spread and Beam Stability due to Landau Damping

octupole, damping, luminosity, feedback

1421

X. Buffat
EPFL, Lausanne, Switzerland
W. Herr, N. Mounet, E. Métral, T. Pieloni
CERN, Geneva, Switzerland

We discuss the Landau damping of coherent instabilities in the presence of betatron tune spread. This tune spread can originate from dedicated non-linear magnets such as octupoles, or through the beam-beam interaction. In the latter case we have to distinguish the contribution from head-on and parasitic beam-beam interactions and the collision pattern of different bunches plays an important role. The interplay of these sources of tune spread and the resulting stability is discussed for the case of the LHC.

TUPFI077

Commissioning Progress of the RHIC Electron Lenses

electron, solenoid, proton, controls

1526

W. Fischer, Z. Altinbas, M. Anerella, M. Blaskiewicz, D. Bruno, W.C. Dawson, D.M. Gassner, X. Gu, R.C. Gupta, K. Hamdi, J. Hock, L.T. Hoff, R.L. Hulsart, A.K. Jain, P.N. Joshi, R.F. Lambiase, Y. Luo, M. Mapes, A. Marone, R.J. Michnoff, T.A. Miller, M.G. Minty, C. Montag, J.F. Muratore, S. Nemesure, D. Phillips, A.I. Pikin, S.R. Plate, P.J. Rosas, L. Snydstrup, Y. Tan, C. Theisen, P. Thieberger, J.E. Tuozzolo, P. Wanderer, S.M. White, W. Zhang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy.
In polarized proton operation, the RHIC performance is limited by the head-on beam-beam effect. To overcome these limitations two electron lenses were installed and are under commissioning. One lens uses a newly manufactured superconducting solenoid, in the other lens the spare superconducting solenoid of the BNL Electron Beam Ion Source is installed to allow for propagation of the electron beam. (This spare magnet will be replaced by the same type of superconducting magnet that is also used in the other lens during the 2013 shut-down.) We give an overview of the commissioning configuration of both lenses, and report on first results in commissioning the hardware and electron beam. We also report on lattice modifications needed to adjust the phase advance between the beam-beam interactions and the electron lenses, as well as upgrades to the proton instrumentation for the commissioning.

TUPFI083

Simulation Study of Head-on Beam-beam Compensation with Realistic RHIC Lattices

dynamic-aperture, proton, resonance, simulation

1541

Y. Luo, M. Bai, W. Fischer, C. Montag, V.H. Ranjbar, S. Tepikian
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We performed numerical simulations to study the effects of head-on beam-beam compensation with the realistic RHIC lattices. To better cancel the beam-beam resonance driving terms during half beam-beam compensation operation, the betatron phase advances between the interaction point IP8 and the center of the electron lens should be multiples of pi. for this purpose two shunt power supplies were added to the main quadrupole circuit buses in the arc between them. For the realistic beam-beam compensation lattices, the integer tunes are (27, 29) for the Blue ring and (29, 30) for the Yellow ring. The betatron phase advances between IP8 and the e-lens are (8pi,11pi) in the Blue ring and (11pi, 9pi) in the Yellow ring. Recent simulation results will be presented.

TUPFI084

RHIC Polarized Proton Operation for 2013

emittance, polarization, injection, resonance

1544

V.H. Ranjbar, L. A. Ahrens, E.C. Aschenauer, M. Bai, J. Beebe-Wang, M. Blaskiewicz, J.M. Brennan, K.A. Brown, D. Bruno, R. Connolly, T. D'Ottavio, K.A. Drees, Y. Dutheil, W. Fischer, C.J. Gardner, J.W. Glenn, X. Gu, M. Harvey, T. Hayes, H. Huang, R.L. Hulsart, A.I. Kirleis, J.S. Laster, C. Liu, Y. Luo, Y. Makdisi, G.J. Marr, A. Marusic, F. Méot, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, S. Nemesure, P.H. Pile, A. Poblaguev, V. Ptitsyn, G. Robert-Demolaize, T. Roser, W.B. Schmidke, V. Schoefer, F. Severino, T.C. Shrey, D. Smirnov, K.S. Smith, D. Steski, S. Tepikian, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, M. Wilinski, K. Yip, A. Zaltsman, A. Zelenski, K. Zeno, S.Y. Zhang
BNL, Upton, Long Island, New York, USA
O. Eyser
UCR, Riverside, California, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The 2013 operation of the Relativistic Heavy Ion Collider (RHIC) marks the second year of running under the RHIC II era. Additionally this year saw the implementation of several important upgrades designed to push the intensity frontier. Two new E-lenses have been installed, along with a new lattice designed for the E-lens operation. A new polarized proton source which generates about factor of 2 more intensity was commissioned as well as a host of RF upgrades from a new longitudinal damper, Landau cavity in RHIC to a new low level RF and new harmonic structure for the AGS. We present an overview of the challenges and results from this years run.

TUPFI086

A Tapered Six Dimensional Cooling Lattice for a Muon Collider

emittance, collider, simulation, focusing

1547

D. Stratakis, R.C. Fernow, R.B. Palmer
BNL, Upton, Long Island, New York, USA

Designs for Neutrino Factories and Muon Colliders use ionization cooling to reduce the emittance of the muon beam prior to acceleration. Two lattices based on the original RFOFO ring design representing different configurations of the magnetic field are considered. One is with a flip magnetic field and one with a non-flip magnetic field configuration that is used to eliminate for possible space-charge effects. The details of the G4Beamline tracking studies of both channels are presented and compared to the independent ICOOL code.

TUPFI087

Alternative Muon Cooling Options based on Particle-Matter-Interaction for a Neutrino Factory

cavity, focusing, solenoid, proton

1550

D. Stratakis
BNL, Upton, Long Island, New York, USA
A. Alekou
CERN, Geneva, Switzerland
D.V. Neuffer, P. Snopok
Fermilab, Batavia, USA
J. Pasternak
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
J. Pasternak
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
C.T. Rogers
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
P. Snopok
Illinois Institute of Technology, Chicago, Illinois, USA

Funding: This work is funded by US Dept. of Energy grant numbers DE AC02-98CH10886
An ionization cooling channel is a tightly spaced lattice containing absorbers for reducing the momentum of the muon beam, rf cavities for restoring the momentum and strong solenoids for focusing the beam. Such a lattice is an essential feature of most designs for Neutrino Factories and Muon Colliders. Here, we explore three different approaches for designing ionization cooling channels with periodic solenoidal focusing. Key parameters such as the engineering constraints that are arising from the length and separation between the solenoidal coils are systematically examined. In addition, we propose novel approaches for reducing the peak magnetic field inside the rf cavities by using either a magnetic shield system or a bucked coils configuration. Our lattice designs are numerically examined against two independent codes: The ICOOL and G4BL code. The feasibility of our proposed cooling channels to muon accelerators is examined by applying the proposed lattices to the front-end of a Neutrino Factory.

TUPFI088

Space-charge Studies for Ionization Cooling Lattices

emittance, space-charge, collider, simulation

1553

D. Stratakis, R.B. Palmer
BNL, Upton, Long Island, New York, USA
D.P. Grote
LLNL, Livermore, California, USA

Funding: This work is funded by US Dept. of Energy grant numbers DE AC02-98CH10886
Intense muon beams provide a promising solution to a variety of applications ranging from nanotechnology to nuclear detections systems and from medical sciences to high energy physics. Production of such intense beam requires the beam to be cooled and ionization cooling via particle matter interaction is considered one of the most practical methods. Here a theoretical and numerical study on space-charge effects on such ionization cooling channels is presented. We show that space-charge can strongly affect the design of muon cooling systems by limiting their minimum cooling rate. Space-charge compensation solutions are discussed and the minimum cooling emittance as a function of the beam charge and pulse width is identified.

TUPME002

Design Integration at the International Linear Collider

positron, electron, damping, civil-engineering

1559

B. List, L. Hagge, J. Kreutzkamp, N.J. Walker
DESY, Hamburg, Germany

In preparation for the Technical Design Report of the International Linear Collider, a comprehensive design of the accelerator has been compiled. DESY has contributed a systematic design integration approach, which helps to achieve a complete, correct and consistent design. We use the lattice as the leading element for design integration. Geometry information including 3D visualization models are derived from the lattice, and are used to ensure that the beamlines fit and suited for access and installation. The 3D models are also used as basis for tunnel and cavern layout. As detailed designs of components become available, the lattice is adjusted and the overall models are iterated. Lists of components are derived from the lattice and are used to generate a component bill of materials, which in turn serves as basis for cost estimation and installation planning. An integrated 3D model of the entire accelerator and all the civil construction elements helps to optimize the design for example with regard to space efficiency, ease of access for installation, and life safety. Setting up design integration in an early project stage results in a better design helps to reduce costs.

TUPME007

Beam Lifetime in Low Emittance Rings

scattering, simulation, background, factory

1574

M. Boscolo
INFN/LNF, Frascati (Roma), Italy

In this paper I will review the main effects in low emittance rings that determine the beam lifetime by causing beam losses along the ring. As an example, the case for a B-factory based on the crab-waist collision scheme has been studied. During the machine design all the effects that determine the beam lifetime and induce backgrounds in the detector have been analyzed in details. The crab-waist scheme provides an higher luminosity, but at the same time it induces higher beam losses at the final focus. For this reason single beam effects such as Touschek and beam-gas scattering have been studied in details, by means of a macroparticle tracking code developed for this purpose*. Also Radiative Bhabha scattering, that is the dominant effect to lifetime and backgrounds has been studied with the same technique to check possible multiturn losses at IR. An efficient collimation system has been designed to intercept scattered particles that would be lost in the IR in both the horizontal and the vertical plane. Recently, the Touschek tracking simulation code has been implemented to study the lifetime behavior for extremely low-emittance rings.
* M. Boscolo and P. Raimondi, “Monte Carlo simulation for the Touschek effect with the crab-waist scheme”, Phys. Rev. ST-AB 15 104201 (2012)

TUPME016

Crosstalk Between Beam-beam Interaction and Lattice Nonlinearities in the SuperKEKB

simulation, luminosity, resonance, betatron

1601

D. Zhou, K. Ohmi, Y. Ohnishi, K. Oide, H. Sugimoto
KEK, Ibaraki, Japan

Momentum-dependent lattice nonlinearities have been proven to be important for the luminosity performance in the KEKB B-factory. As an upgrade of KEKB, the SuperKEKB adopts nano-beam scheme, in which the colliding beams are squeezed to extremely small sizes at the interaction point. Consequently, the lattice nonlinearities in SuperKEKB become more stronger than in KEKB. Using two codes, SAD and BBWS, we did various simulations to study the crosstalk between beam-beam interaction and lattice nonlinearities. It is found that lattice nonlinearities can cause remarkable luminosity loss in the SuperKEKB.

TUPME022

Study on the Single Bunch Transverse Emittance Growth in BAPS

emittance, wakefield, vacuum, wiggler

1619

J. Gao, D. Wang
IHEP, Beijing, People's Republic of China

Funding: Supported by the National Foundation of Natural Sciences Contract 11175192.
Beijing Advanced photon Source (BAPS) is a proposed next synchrotron radiation facility which has much smaller transverse emittance after SSRF in China, with 5 GeV energy and 1.5 km circumference. In order to explore how small the transverse emittance we can get on BAPS, this paper studies the single bunch transverse emittance growth due to short range wakefield according to J. Gao’ theory. The mechanism of wakefield induced single bunch emittance is explained first and then the transverse emittance at the design beam current is estimated. Also, the tolerances for the transverse loss factor and the vacuum chamber misalignment (or the closed orbit distortion) are presented.

TUPME055

Strawman Optics Design for the CERN LHeC ERL Test Facility

linac, optics, emittance, electron

1694

A. Valloni, O.S. Brüning, R. Calaga, E. Jensen, M. Klein, R. Tomás, F. Zimmermann
CERN, Geneva, Switzerland
S.A. Bogacz, D. Douglas
JLAB, Newport News, Virginia, USA

In preparation for a future Large Hadron electron Collider (LHeC) at CERN, an ERL test facility is foreseen as a test bed for SRF development, cryogenics, and advanced beam instrumentation, as well as for studies of ERL-specific beam dynamics. The CERN ERL test facility would comprise two linacs, each consisting of 4 superconducting 5-cell cavities at 802 MHz, and two return arcs on either side. With an RF voltage of 75 MeV per linac a final electron energy of about 300 MeV is reached. The average beam current should be above 6 mA to explore the parameter range of the future LHeC. In this paper we present a preliminary optics layout.

TUPME064

Envelope Perturbations in a Space-Charge-Dominated Electron Beam

simulation, resonance, space-charge, quadrupole

1712

W.D. Stem, B.L. Beaudoin, I. Haber, R.A. Kishek, T.W. Koeth
UMD, College Park, Maryland, USA

Funding: Supported by the US Dept. of Energy, Office of High Energy Physics, and by the US Dept. of Defense, Office of Naval Research and the Joint Technology Office.
Linear perturbation analysis of the RMS envelope equations predicts a frequency splitting of the transverse envelope resonances with the onset of space charge. These resonances are a potential source of beam degradation for space-charge-dominated particle accelerators and storage rings. We use WARP for both envelope code integration and particle-in-cell (PIC) simulations to predict the behavior of these resonances for an existing alternating gradient lattice storage ring. The focus of these simulations is tailored toward examining physics that is scalable to future high-intensity accelerators. This paper provides detailed simulation results and a design for an experimental demonstration at the University of Maryland Electron Ring (UMER), a high intensity 10 keV electron storage ring.

TUPME065

Experimental Study of Horizontal-Longitudinal Coupling at CesrTA

coupling, cavity, simulation, scattering

1715

M. P. Ehrlichman, A. Chatterjee, W. Hartung, D.P. Peterson, N.T. Rider, D. L. Rubin, J.P. Shanks, S. Wang
CLASSE, Ithaca, New York, USA

Funding: This research was supported by NSF and DOE contracts PHY-0734867, PHY-1002467, PHYS-1068662, DE-FC02-08ER41538, DE-SC0006505.
In storage rings, the presence of horizontal dispersion in the RF cavities introduces x-z coupling. The result is that the beam is skewed in the horizontal-longitudinal plane. The skew angle is proportional to the V15 term of the 6X6 coupling matrix which is proportional to the RF cavity voltage and the horizontal dispersion in the cavity. Here we report experiments at CesrTA where x-z coupling was explored using three distinct lattice configurations with different V15 coupling terms. We explore x-z coupling for each of these lattices by measuring the horizontal projection of the beam with a beam size monitor, as the RF voltage is varied. The first lattice has about 1 m dispersion in the RF cavities, resulting in a V15 term at the beam size monitor source point corresponding to 16 mrad x-z tilt. In the second, the V15 generated in one pair of cavities is compensated at the second pair by adjusting the horizontal betatron phase advance between the cavity pairs. In the third, the optics are adjusted so that the RF cavity region is dispersion-free, eliminating the coupling entirely. Additionally, intra-beam scattering is evident in our measurements of beam size vs. RF voltage.

TUPWA020

The Implementation of Equipartitioning in the Proton Linac Code PADSC

emittance, space-charge, quadrupole, linac

1766

Y.L. Zhao, S. Fu, Z. Li
IHEP, Beijing, People's Republic of China

The high intensity accelerator projects place extremely stringent requirements on particle loss, since even very small losses can lead to unacceptably high levels of radioactivity that can hinder or prevent hands-on maintenance. Such losses are known to be associated with emittance growth and beam halo. Non-equipartitioning contributes a lot for emittance growth and beam halo. The present equipartitioning realization has assumed that the emittance and space charge force are keeping constant, which will induce errors. The implementation in the proton linac code PADSC does equipartitioning optimization according to the real space charge force and emittance in the quasi period lattice.

TUPWA045

Longitudinal Space Charge Effects in the CLIC Drive Beam

space-charge, simulation, quadrupole, luminosity

1811

R.L. Lillestøl, S. Döbert, A. Latina, D. Schulte
CERN, Geneva, Switzerland
E. Adli, K.N. Sjobak
University of Oslo, Oslo, Norway

The CLIC main beam is accelerated by rf power generated from a high-intensity, low-energy electron drive beam. The accelerating fields are produced in Power Extraction and Transfer Structures, and are strongly dependent on the drive beam bunch distribution, as well as other parameters. We investigate how longitudinal space charge affects the bunch distribution and the corresponding power production, and discuss how the bunch length evolution can affect the main beam. We also describe the development of a Particle-in-Cell space charge solver which was used for the study.

TUPWA046

Experimental Results from the Test Beam Line in the CLIC Test Facility 3

emittance, simulation, quadrupole, extraction

1814

R.L. Lillestøl, S. Döbert, M. Olvegård
CERN, Geneva, Switzerland
E. Adli
University of Oslo, Oslo, Norway

In the CLIC two-beam scheme, the main beam is accelerated by rf power provided by energy extraction from a secondary drive beam. This energy is extracted in decelerators, and the first prototype decelerator is the Test Beam Line in the CLIC Test Facility 3. The line is currently equipped with 12 Power Extraction and Transfer Structures (PETS), which allows for extracting up to 40% of the beam energy. We correlate the measured deceleration with predictions from the beam current and the rf power produced in the PETS. We also discuss recent bunch length measurements and how it influences the deceleration. Finally we look at the evolution of the transverse emittance.

TUPWA057

Effects of Transient CSR Wakefields on Microbunching in a Bunch Compressor

wakefield, impedance, radiation, FEL

1832

C.E. Mitchell, J. Qiang
LBNL, Berkeley, California, USA

Funding: Supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The standard analytical model of CSR-induced microbunching in a bunch compressor chicane makes use of a steady-state 1-D model of the longitudinal CSR interaction. This model is numerically generalized to include the effects of transient CSR wakefields due to bend entry and exit, as well as CSR that is generated in upstream bends and propagates across one or more lattice elements before interacting with the beam. The resulting linear integral equation for CSR-induced microbunching is solved numerically for the second bunch compressor of a proposed Next Generation Light Source.

TUPWO001

A New 5BA Low Emittance Lattice for Sirius

emittance, dipole, sextupole, coupling

1874

L. Liu, N. Milas, A.H.C. Mukai, X.R. Resende, A.R.D. Rodrigues, F. H. de Sá
LNLS, Campinas, Brazil

Sirius is a third-generation low emittance synchrotron light source under construction at LNLS, the Brazilian Synchrotron Light Laboratory. A new 5BA lattice was designed in replacement for the previous TBA lattice with the aim to reduce the emittance to sub-nm.rad values. The new design has a circumference of 518 m with 20 achromatic straight sections and a natural emittance of 0.28 nm.rad at 3 GeV for the bare lattice (without IDs). The dipoles combine low 0.58 T field magnets for the main beam deflection with a 2 T short superbend magnet sandwiched in the center dipole. This creates a longitudinal dipole gradient that is used both to lower the emittance and to provide hard X-ray dipole sources.

TUPWO003

CLIC 3 TeV Beam Size Optimization with Radiation Effects

radiation, quadrupole, dipole, photon

1877

O.R. Blanco, P. Bambade
LAL, Orsay, France
R. Tomás
CERN, Geneva, Switzerland

Horizontal beamsize contribution due to radiation on bending magnets is calculated using theoretical results and recent improvements in mapclass (Mapclass2). In order to verify the code and validity of its approximations, a simple lattice with no geometrical nor chromatic aberrations, one dipole and a final drift has been used to compare Mapclass2 calculations and Placet tracking results. CLIC 3TeV lattice is optimized including the radiation effects. Current results show that correction of chromatic aberrations impose constraints in radiation improvement.

TUPWO005

Survey of Beam Optics Solutions for the MLS Lattice

optics, emittance, quadrupole, cavity

1883

M. Ries, J. Feikes, T. Goetsch, G. Wüstefeld
HZB, Berlin, Germany

The Metrology Light Source (MLS) is an electron storage ring containing 24 quadrupole magnets which can be powered individually. Fully exploring the capabilities of the machine optics by tracking or experiment would be very time consuming. Therefore the quadrupoles were combined in five families and a numerical brute force approach was used to scan for areas of stable solutions in the scope of linear beam optics. In order to get information on the expected beam lifetimes for each generated optics, a model for the Touschek lifetime was implemented. Simulation results as well as experimental tests of selected optics will be presented.

TUPWO015

Off-Energy Injection Into Newsubaru

injection, septum, synchrotron, betatron

1913

Y. Shoji
LASTI, Hyogo, Japan
Y. Minagawa, Y. Takemura
JASRI/SPring-8, Hyogo-ken, Japan

NewSUBARU is temporarily operated in non-achromatic mode for the research using chromaticity modulation. At this special mode, a normal injection scheme does not work because of the larger stored beam size and smaller ring acceptance. In order to obtain good injection efficiency, which enables top-up operation, the injected beam energy is displaced from the ring energy. The finite dispersion of 1.1 m at the injection point and the energy displacement of 0.7% reduce the betatron oscillation amplitude of the injected beam. A trade off is a synchrotron oscillation produced by the energy mismatch. Using this technique, it became possible to inject new beam using a closed fast injection bump and also a top-up operation. Although it is not possible to inject beam to a normal achromatic lattice using a closed bump. Especially in non-achromatic quasi-isochronous ring, it would be possible that the energy mismatch is reduced by the betatron amplitude dependent shift of the equilibrium energy.

TUPWO022

Space Charge Effects Study and Optimization in CSNS/LRBT

space-charge, emittance, linac, injection

1928

Z.P. Li, N. Huang, W.B. Liu, S. Wang
IHEP, Beijing, People's Republic of China

The linac to ring beam transport line (LRBT) of China Spallation Neutron Source (CSNS) connecting the linac and the rapid cycling synchrotron (RCS) transports 80 MeV negative hydrogen ions (H⁻) beams for RCS injection. Space charge effect in LRBT is significant due to small emittance and high current density of the beam, which is a major cause of emittance growth and beam loss. An achromatic transverse optical matching was performed by TRACE 3D code. Emittance growths of beams with different initial distributions in different LRBT lattices were studied separately. Simulation results show that the LRBT design with triplet can mitigate the emittance growth by lattice optimization of the front matching section and no beam loss occurs at 15mA. The location and parameters of the debuncher in LRBT were also optimized to reduce the momentum spread and energy jitter.

TUPWO033

Effects Estimation of Superconducting Wiggler in SSRF

emittance, dynamic-aperture, optics, quadrupole

1946

Q.L. Zhang, B.C. Jiang, S.Q. Tian, W.Z. Zhang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

Superconducting wiggler (SW) may greatly impact on the beam dynamics in a storage ring. The effects of a 4.5T SW has been studied in SSRF including impaction on the emittance and the energy spread. To keep an undegraded storage ring performance, a local achromatic lattice is considered. The combat between the damping effect of the SW and emittance growth of local achromatic lattice is the main concern of this paper. Other effects (tune shift, beta beating, dynamics aperture, etc.) with the SW are also simulated and optimized in this paper.

TUPWO035

Physical Design of Beam Transport Line of a Compact Terahertz FEL

undulator, quadrupole, electron, FEL

1952

H. Zeng, Q.S. Chen, Q. Fu, B. Qin, B. Wu, Y.Q. Xiong
HUST, Wuhan, People's Republic of China
G. Feng, Y.J. Pei
USTC/NSRL, Hefei, Anhui, People's Republic of China

The single pass, linac-based compact terahertz source at HUST is now in the physical design stage. To match Twiss parameters and dispersion function of the electron beam at the undulator entrance and get smaller beta function in the whole line, several lattices based on the double bending achromat(DBA) structure were discussed and the optimized design is given with beam dynamics results–calculated by MAD and Trace 3D.

TUPWO042

Modeling Results from Magnetic and Beam Based Measurements of the ALBA Gradient Dipoles

dipole, focusing, quadrupole, storage-ring

1967

X. Gavaldà
SOLEIL, Gif-sur-Yvette, France
G. Benedetti, J. Marcos, Z. Martí
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

The ALBA lattice is a DBA-like structure where most of vertical focusing is provided by gradient dipoles. In the first year of machine operation, the model parameters describing the focusing strength of the 32 dipoles have been calibrated by fitting the measured closed orbit response matrix. The mean k-value obtained from this analysis differs by -0.3% with respect to the value taken from the magnetic measurements previous to the magnet installation, while the k variation within the 32 dipoles is of the same order of magnitude. The optics results (tunes, beta beating, dispersion) obtained with the beam based model are compared with the predicted ones from the magnetic measurement model.

TUPWO063

Reducing HLS-II Emittance by Radiation Damping Partition Factor Exchange

wiggler, emittance, storage-ring, damping

2009

J.Y. Li
FEL/Duke University, Durham, North Carolina, USA
W. Li, G. Liu, W. Xu
USTC/NSRL, Hefei, Anhui, People's Republic of China
Y. Li
BNL, Upton, Long Island, New York, USA

Funding: The Introduction of Outstanding Technological Talents Program of Chinese Academy of Sciences, 2010.
In this paper, we present a preliminary study on using a Robinson wiggler, a wiggler with transverse gradient, to reduce the horizontal beam emittance of the Hefei Light Source II (HLS-II) storage ring. A proof-of-principle study demonstrates that it is possible to further reduce the horizontal beam emittance by 50\% using a 2-meter long Robinson wiggler installed on a dispersive straight section. This encouraging result suggests a feasible option to significantly improve the HLS-II performance at a relative low cost and without significant modification to its global configuration in the near future.

TUPWO069

Optimization of FACET Optics

sextupole, optics, chromatic-effects, simulation

2024

M.-H. Wang, F.-J. Decker, N. Lipkowitz, Y. Nosochkov, G.R. White, U. Wienands, M. Woodley, G. Yocky
SLAC, Menlo Park, California, USA

Funding: supported by the US Department of Energy contract DE-AC02-76SF00515.
The FACET accelerator facility is designed to provide short and intense e^- or e⁺ bunches with small spot size for plasma wakefield accelerator research and other experiments. It is based on the SLAC linac with a compressor chicane in sector-10, and a second compressor chicane and final focus in sector-20 (S20). Originally, the S20 chicane was designed to be compatible with an upgrade to include a second S20 chicane for simultaneous transport of e^- and e⁺ bunches. This placed additional optics constraints which lead to strong focusing in the S20 chicane. The latter increases the effects of errors causing emittance growth. Lately, it has been decided not to proceed with the upgrade option. Therefore, there is a potential for improving the optics by relaxing the constraints. In this study, we explore alternative optics designs where beta functions in the S20 chicane and final focus are reduced in order to minimize the error effects. The optics and non-linear aberrations are evaluated, and the chromatic correction is optimized for each design. Beam tracking simulations are performed using Elegant and Lucretia. The most optimal designs are identified based on these simulations.

WEPWA060

The Kharkov X-ray Generator Facility NESTOR

storage-ring, electron, controls, injection

2253

A.A. Shcherbakov, V.P. Androsov, N. Ayzatsky, V.N. Boriskin, E.V. Bulyak, A.N. Dovbnya, P. Gladkikh, A.N. Gordienko, V.A. Grevtsev, A. Gvozd, V.E. Ivashchenko, A.A. Kalamayko, I.I. Karnaukhov, I.M. Karnaukhov, V.P. Kozin, V.A. Kushnir, V.P. Lyashchenko, V.S. Margin, N.I. Mocheshnikov, V.V. Mytrochenko, A. Mytsykov, I.M. Neklyudov, T.F. Nikitina, F.A. Peev, O.V. Ryezayev, V.L. Skirda, V.A. Skomorokhov, Y.N. Telegin, V.I. Trotsenko, A.Y. Zelinsky, O.D. Zvonarjova
NSC/KIPT, Kharkov, Ukraine
J.I.M. Botman
TUE, Eindhoven, The Netherlands
I.V. Drebot
LAL, Orsay, France

The last few years the sources of the X-rays NESTOR based on a storage ring with low beam energy and Compton scattering of intense laser beam are under design and development in NSC KIPT. The main task of the project is to develop compact intense X-ray generator on the base of relatively cheap accelerator equipment and up-to-date laser technologies. The paper is devoted to description of the last results on construction and commissioning of the facility.

WEPWO004

Studies of Systematic Flux Expulsion in Superconducting Niobium

niobium, cavity, simulation, controls

2316

J.M. Vogt, J. Knobloch, O. Kugeler
HZB, Berlin, Germany

The quality factor Q0 that can be obtained in a superconducting cavity is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We believe that cooling conditions have an additional impact, as they appear to influence the amount of trapped flux and hence the residual resistance. We have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach Tc from below in the superconducting state. Although the sample remains in the superconducting state, a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Furthermore, simulations using the Radia software package for Mathematica developed by the ESR were used to better unterstand the measured changes in magnetic flux around the Sample. Applying a similar procedure for minimization of trapped magnetic flux to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q0.

WEPEA008

Influence of Higher Order Phase Slip Factor Contributions on Beam Loss during SIS-100 Proton Operation

quadrupole, sextupole, simulation, dynamic-aperture

2507

S. Sorge, O. Boine-Frankenheim, G. Franchetti
GSI, Darmstadt, Germany

The projected FAIR synchrotron SIS-100 is envisaged to accelerate intense proton and heavy-ion beams. The maximum proton energy will be E=29 GeV. In order to stay below transition energy a special powering scheme of the quadrupoles has been introduced which provides a maximum transition gamma of 45.5. The resulting settings of the quadrupole focusing strengths generate large maxima of the horizontal beta and dispersion functions. In particle tracking simulation we observed beam loss caused by a large momentum spread in the deformed rf bucket close to transition. Application of the chromaticity correction sextupoles led to a reduction of the first-order phase slip factor term and of the beam losses. In this contribution we will analyze the effect of the sextupoles on the higher-order components of the phase slip factor. The rf bucket shape will be discussed as well as the transverse beam loss and possible longitudinal instabilities.

WEPEA012

Study of Laser Wakefield Accelerators as Injectors for Synchrotron Light Sources

laser, synchrotron, simulation, storage-ring

2519

S. Hillenbrand, V. Judin, A.-S. Müller
KIT, Karlsruhe, Germany
R.W. Aßmann, S. Hillenbrand
CERN, Geneva, Switzerland
O. Jansen, A.M. Pukhov
HHUD, Dusseldorf, Germany

Short bunch lengths, high beam energies, and small facility footprint make Laser Wakefield Accelerators (LWFA) very interesting as injectors for Synchrotron Light Sources. In this paper, we describe exemplary investigations for the ANKA storage ring.

WEPEA022

Analytical Estimations of the Dynamic Apertures of Beams with Momentum Deviation and Application in FFAG

dynamic-aperture, sextupole, positron, simulation

2546

M. Xiao, J. Gao
IHEP, Beijing, People's Republic of China

Analytical formulae for estimating the dynamic apertures of synchrotron particles has been well established. Based on the standard mapping, we extend the analytical formulae of dynamic aperture for off-momentum particles in circular accelerator. And we compare the analytical results with the simulation ones in the BEPC-II positron ring lattice under some conditions. What's more, we give the analytical formulae of dynamic aperture for FFAG in the similar way.

WEPEA023

Space Charge Effects for Different CSNS/RCS Working Points

resonance, simulation, space-charge, emittance

2549

S.Y. Xu, N. Wang, S. Wang
IHEP, Beijing, People's Republic of China

The China Spallation Neutron Source (CSNS) operates at 25 Hz repetition rate with the design beam power of 100 KW. CSNS consists of an 80-MeV linac and a 1.6-GeV Rapid Cycling Synchrotron (RCS). Due to the high beam density and high repetition rate for CSNS/RCS, the rate of beam loss must be controlled to a very low level. The major source of beam loss is associated with resonances. Thus, choosing he best suitable working points on the tune diagram is important to reach low beam loss. Different tune areas are explored and compared by considering resonances and the effects of space charge, which can drive particles into the excited resonances. Different working points are simulated and compared by using the codes ORBIT and SIMPSONS.

WEPEA025

Chromatic Sextupole Pair Optimization Methods for Enlarging Dynamic Aperture

sextupole, dynamic-aperture, focusing, storage-ring

2555

Z. Bai, Q.K. Jia, W. Li, L. Wang, Q. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Based on the step-by-step chromaticity compensation method [1] and artificial intelligence algorithms, we propose new numerical methods, called chromatic sextupole pair optimization methods, for enlarging the dynamic aperture of electron storage rings. In the new methods, the decision variables related to chromatic sextupole pairs are optimized using artificial intelligence algorithms to enlarge the dynamic aperture. We demonstrate that the new methods are equivalent to the recently used numerical method, in which the decision variables, sextupole strengths, are optimized using artificial intelligence algorithms.
[1] E. Levichev, P. Piminov, Proceedings of EPAC 2006, p. 2116.

WEPEA029

The SHER-HIAF Ring Lattice Design

injection, quadrupole, ion, kicker

2561

X. Gao, W.P. Chai, G.D. Shen, J. Shi, J.W. Xia, J.C. Yang
IMP, Lanzhou, People's Republic of China

Super Heavy Experimental Ring (SHER) is one of the rings of the next accelerator complex High Intensity Heavy Ion Accelerator Facility (HIAF) at IMP[4]. Here, present ideas of the lattice design for the operation of the large acceptance ring are presented. The SHER ring has to be optimized for e-cooling and the lattice is designed for different modes. First of all, it is designed in the so called isochronous mode as time-of-flight mass spectrometer for short-lived secondary nuclei. Secondly, SHER can also be used to be a storage ring for collecting and cooling the secondary rare isotope beams from the transport line. In order to fulfill it's purpose, the ion optics can be set to different ion optical modes

WEPEA037

Testing of Symplectic Integrator of Spin-orbit Motion Based on Matrix Formalism

simulation, storage-ring, electromagnetic-fields

2582

A.N. Ivanov, S.N. Andrianov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia
R. Maier, Y. Senichev, D. Zyuzin
FZJ, Jülich, Germany

Investigation of spin-orbital motion in electromagnetic fields requires different numerical methods. Approaches for long-term evolution modelling need both performance and symplecticity. In this paper we discuss matrix maps method for numerical simulation. We examine symplectification and accuracy in terms of electostatic storage ring. The results are compared with traditional symplectic step-by-step methods.

WEPEA050

Analysis of Possible Functional Forms of the Scaling Law for Dynamic Aperture as a Function of Time

dynamic-aperture, luminosity, beam-losses, simulation

2618

M. Giovannozzi, R. De Maria, F. Lang
CERN, Geneva, Switzerland

Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.
In recent studies, the evolution of the dynamic aperture with time has been fitted with a simple scaling law based on a limited number of free parameters. In this paper, different approaches to improve the numerical stability of the fit are presented, together with a new functional form. The results are discussed in details and applied to a set of numerical simulations for the LHC.

WEPME056

Application of Z-transform to Noise Response Modeling of a Bunch-by-bunch Feedback System

feedback, storage-ring, pick-up, monitoring

3058

C. Yao, N.P. Di Monte, A.J. Scaminaci, H. Shang
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-ACO2-O6CH11357.
The APS storage ring has an electron beam energy of 7 GeV and a single current of up to 16 mA. Transverse beam instability is corrected by a combination of chromatic correction and bunch-by-bunch feedback system. Noises produced in the pickup circuits is processed and transferred to the beam the same as a beam signal, which contributes to beam motion when the loops are closed. By analyzing the input data stream of the feedback system, one can passively obtain useful information, such as the tunes, loop stability, noise spectrum, etc. This approach has been reported by J. Klute and D. Teytelman. We implemented a passive and continuous tune monitoring process at the APS storage ring. In order to understand the underlying principle, we applied z-transform analysis to the noise-response model of a bunch-by-bunch feedback system. Our analysis shows a clear relationship between the spectrum of the noise response and the open-loop response of the beam. The noise-response model can also be applied to other areas, such as stability and noise analysis of a bunch-by-bunch feedback system. This report presents our analysis and some experimental data.

THYB101

Suppressing Transverse Beam Halo with Nonlinear Magnetic Fields

resonance, space-charge, damping, octupole

3099

S.D. Webb, D.T. Abell, D.L. Bruhwiler, J.R. Cary
Tech-X, Boulder, Colorado, USA
V.V. Danilov
ORNL, Oak Ridge, Tennessee, USA
S. Nagaitsev, A. Valishev
Fermilab, Batavia, USA

Funding: This work was supported in part by the US Department of Energy's Office of Science, Office of High Energy Physics, under grant No. DE-SC0006247.
Traditional space charge driven resonances, such as beam halo, arise due to the underlying linear nature of accelerator lattices. In this talk, we present initial results on a new class of intrinsically nonlinear lattices, which introduce a large tune spread naturally. The resulting nonlinear decoherence suppresses the onset of beam halo.

Slides THYB101 [63.510 MB]

THOBB102

Beam Coupling Impedance Localization Technique Validation and Measurements in the CERN Machines

impedance, kicker, quadrupole, betatron

3106

N. Biancacci, G. Arduini, T. Argyropoulos, H. Bartosik, R. Calaga, K. Cornelis, S.S. Gilardoni, N. Mounet, E. Métral, Y. Papaphilippou, S. Persichelli, G. Rumolo, B. Salvant, G. Sterbini, R. Tomás, R. Wasef
CERN, Geneva, Switzerland
M. Migliorati, L. Palumbo
URLS, Rome, Italy

The beam coupling impedance could lead to limitations in beam brightness and quality, and therefore it needs accurate quantification and continuous monitoring in order to detect and mitigate high impedance sources. In the CERN machines, for example, kickers and collimators are expected to be the main contributors to the total imaginary part of the transverse impedance. In order to detect the other sources, a beam based measurement was developed: from the variation of betatron phase beating with intensity, it is possible to detect the locations of main impedance sources. In this work we present the application of the method with beam measurements in the CERN PS, SPS and LHC.

Slides THOBB102 [7.224 MB]

THPPA02

Features and Applications of the Program ELEGANT

simulation, electron, linac, FEL

3139

M. Borland
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.
ELEGANT is an open-source accelerator design and simulation code that has been in use and development for nearly two decades. In that time, it has evolved into a fairly general code for the design and modeling of linacs and storage rings, due in no small measure to suggestions and feedback from users world-wide. The code is best known for modeling of linacs for free electron lasers and particularly its relatively fast and straightforward modeling of coherent synchrotron radiation in magnetic bunch compression systems. This capability led to the discovery of a microbunching instability in such systems, thus helping to seed a new field of research. ELEGANT's capabilities are enhanced by the use of self-describing data files and the Self-Describing Data Sets (SDDS) toolkit. In this paper, we briefly review the features and capabilities of the code, then give a series of application examples from simulation of linear accelerators and storage rings.

Slides THPPA02 [0.477 MB]

THPEA057

Compensation Schemes for Operation of FEL Wigglers on Duke Storage Ring

wiggler, FEL, storage-ring, quadrupole

3270

J.Y. Li, H. Hao, S.F. Mikhailov, V. Popov, W. Wu, Y.K. Wu
FEL/Duke University, Durham, North Carolina, USA

Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033.
The Duke FEL is the photon driver for the High Intensity Gamma-ray Source (HIGS). To extend the capabilities of the FEL and HIGS to higher photon energy regions, a FEL wiggler switchyard system was developed in the recent years. This system was installed and commissioned in 2012. The FEL wiggler switchyard is used to change between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight section in a short period of time (a few days). With a total of six electromagnetic wigglers, the Duke FEL can be operated in a number of wiggler configurations and with a wide range of magnetic fields. The operation of uncompensated FEL wigglers can cause significant changes to the electron beam closed orbit and magnetic lattice. To maintain a sufficiently large dynamic aperture for an efficient injection and good beam lifetime, a set of complex compensation schemes, including magnetic field and lattice compensation, have been developed for the operation of the FEL wigglers. This paper reports the overall architecture and performance of the FEL wiggler compensation schemes and their implementation in the accelerator controls system using the feedforward mechanism.

THPEA059

Database for Accelerator Modeling

controls, simulation, monitoring, extraction

3273

C.P. Chu, J. Wu
SLAC, Menlo Park, California, USA
D. Dohan, G. Shen
BNL, Upton, Long Island, New York, USA
H.H. Lv
IHEP, Beijing, People's Republic of China
Y. Zhang
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661.
A database for model data is design for the Facility for Rare Isotope Beams (FRIB) Project. The database schema design takes most general approach and is not limited to FRIB models. Programmatically access to the database can be done through a set of Application Programming Interfaces (APIs). Initial data population demonstrates that the database is suitable for XAL application framework. The model database is also part of a collaboration for complete database needs among various domains across an accelerator.

THPWO027

Lattice and Error Studies for J-PARC Linac Upgrade to 50mA/400MeV

emittance, linac, simulation, focusing

3818

Y. Liu
KEK/JAEA, Ibaraki-Ken, Japan
M. Ikegami
J-PARC, KEK & JAEA, Ibaraki-ken, Japan

Equi-partitioning (EP) setting is applied as base-line design for the J-PARC linac upgrade from present 15mA/181MeVto 50mA/400MeV H⁻ beam. We also studied the possibility of mitigating the intra-beam stripping (IBSt) with constant-envelop setting for the frequency jump from 324MHz to the 972MHz ACS section. Since the constant-envelop setting here for the frequency jump is away from equi-partitioning and close to the resonances kz=3kx, kz=2kx and so on, considerable emittance exchange and mismatch were found in the simulation. It is natural to continue the work to explore the parameter space around the above two typical settings. Three key points are to be checked. The first is the tradeoff between the envelopes big enough to suppress the IBSt and tunes not to be too depressed to the space charge region. The second point is the sensitivity of these lattices vs. errors. The third is about the criterion of mismatch in the presence of emittance exchange. When emittance exchange is serious the mismatch can be unavoidable. So it is crucial to ensure the settings are in the safe region free from un-controlled mismatch.

THPWO090

MEBT Design for the Front End Test Stand Project at RAL

quadrupole, cavity, diagnostics, emittance

3969

M. Aslaninejad, J.K. Pozimski, P. Savage
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

The Front End Test Stand (FETS) linear accelerator at Rutherford Appleton laboratory (RAL) will accelerate a 60 mA, 2 ms, 50 pps H⁻ beam up to 3 MeV. A new lattice design for the Medium Energy Beam Transport (MEBT) with a fast-slow chopping system is presented. Beam dynamic simulation has shown very good particle transmission in this new lattice with space charge effects included. The beam energy distribution on the beam choppers dumps is also calculated.

THPWO091

Staging Scenarios for Project-X

linac, emittance, rfq, acceleration

3972

N. Solyak, J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A. Saini, A. Vivoli, V.P. Yakovlev
Fermilab, Batavia, USA

Funding: US DOE under contract DE-AC02-76CH03000.
Project-X is a high intensity proton source in development at Fermilab. At its heart is a linac based on superconducting technology comprising two distinct sections. The first one operates in CW mode and delivers beam with a flexible time structure to simultaneous experimental programs at 1 and 3 GeV. The second one operates in pulsed mode and accelerates a modest fraction (5%) of the beam from 3 GeV to 8 GeV for accumulation in the existing Main Injector complex. In an era of constrained budgets, construction in stages -with each stage capable of supporting worthy scientific programs - may be advantageous. Requirements for each program, coupled to the physical constraints imposed by the Fermilab site have led to a few possible scenarios, which are discussed in this contribution. In particular, we examine the implications of introducing bends in the linac at 1 and 3 GeV in terms of overall performance, flexibility and cost.