IPAC2015 - List of Keywords (focusing)

Paper	Title	Other Keywords	Page
MOPWA037	Mirror Symmetric Chicane-Type Emittance Exchange Beamline with Two Deflecting Cavities	quadrupole, emittance, cavity, dipole	190
	V. Balandin, W. Decking, N. Golubeva DESY, Hamburg, Germany
	Among optical systems for transverse-to-longitudinal emittance exchange (EEX) chicane-type beamlines are of keen interest, because they do not alter the beam propagation direction. Several designs of such beamlines involving a single dipole-mode cavity (TDC) are known. In this paper we present a chicane-type EEX beamline utilizing two TDCs instead of one. The advantages of this beamline are that it is mirror symmetric and does not require an additional accelerating mode cavity for compensation of the so-called thick-lens effect, and, in the compact design, it allows better control of the beam focusing in the non-bending plane than known beamlines with one TDC.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWA037
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MOPWA038	Sensitivity of Linac Optics to Focusing and Energy Errors	optics, linac, operation, quadrupole	193
	V. Balandin, W. Decking, N. Golubeva DESY, Hamburg, Germany
	The ability to control beam optics in the presence of such imperfections as focusing and energy gain errors is essential for a successful operation of high brightness electron linacs providing beams for free-electron lasers. We characterize the cumulative effect of these imperfections using the value of mismatch parameter calculated at the linac exit and show how it depends on the design of the focusing lattice.
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MOPJE023	3D Computer Simulations of the Ultrarelativistic Beam Dynamics in Super Colliders	simulation, collider, experiment, plasma	326
	M.A. Boronina, V.A. Vshivkov ICM&MG SB RAS, Novosibirsk, Russia G. Dudnikova ICT SB RAS, Novosibirsk, Russia
	Funding: The work is supported by RFBR Grants 14-01-31088, 14-01-00392, 14-07-00241. The problem of numerical modeling of beam-beam interaction with high relativistic factor (~10⁴) is considered. We present 3D a self-consistent simulation model based on particle-in-cell method. The mixed Euler-Lagrangian decomposition is used in parallel algorithm for achieving good load balancing and reducing communication cost. Stable regimes of beam dynamics, depending on the beams configuration (beta-function, emittance, energy, currents and relative offset) can be found on the base of the model. In the calculations we used 10⁸ particles on the grid 100x100x100, the number of processors depends highly on the beam shape. The Lomonosov Super Computer and Siberian Supercomputer Centre cluster were used to perform the presented simulations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPJE023
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MOPJE043	Design and Optimization of Electrostatic Deflectors for ELENA	vacuum, antiproton, alignment, simulation	382
	D. Barna University of Tokyo, Tokyo, Japan W. Bartmann, M.A. Fraser, R. Ostojić CERN, Geneva, Switzerland
	The ELENA ring will decelerate the antiprotons ejected from the Antiproton Decelerator (AD) at 5.3 MeV down to 100 keV kinetic energy. The slow antiprotons will be delivered to experiments using electrostatic beamlines, consisting of quadrupoles, correctors and deflectors. An extensive simulation study was carried out to find solutions to minimize the aberrations of the deflectors. These solutions will be presented together with the actual design of these devices.
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MOPJE084	Particle-in-cell Simulations of a Plasma Lens at Daresbury Laboratory	plasma, emittance, simulation, experiment	518
	K. Hanahoe, O. Mete, G.X. Xia UMAN, Manchester, United Kingdom D. Angal-Kalinin, J.K. Jones STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom J.D.A. Smith TXUK, Warrington, United Kingdom
	Feasibility of a focusing element using the transverse fields provided by a plasma cell was studied numerically. In this paper, an experimental set up is proposed for various beam parameters available from the VELA and CLARA beam lines at Daresbury Laboratory. 2D simulation results from VSim, and expected results from planned measurement stations are presented. Field properties and the advantages and disadvantages of such an instrument compared to conventional focusing elements are discussed.
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MOPMA016	Coupler RF Kick in the Input 1.3 GHz Accelerating Cavity of the LCLS-II Linac	cavity, HOM, accelerating-gradient, emittance	571
	A. Lunin, N. Solyak, A.I. Sukhanov, V.P. Yakovlev Fermilab, Batavia, Illinois, USA
	Main and HOM couplers break the cavity axial symmetry, distort RF field and, thus, create a transverse kick, even for a particle moving along the cavity axes. Dependence of a kick on the RF phase causes a beam emittance dilution and degrade the FEL radiation quality. The transverse kick is most dangerous for a beam passing through the first accelerating structure of a linac, where particles energy and their relativistic mass are low. In the paper we analyze the coupler RF kick in the first accelerating structure of the LCSL-II linac.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPMA016
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MOPMA028	Chromaticity and Dispersion in Nonlinear Integrable Optics	lattice, optics, dynamic-aperture, octupole	608
	S.D. Webb, D.L. Bruhwiler RadiaSoft LLC, Boulder, Colorado, USA V.V. Danilov ORNL, Oak Ridge, Tennessee, USA S. Nagaitsev, A. Valishev Fermilab, Batavia, Illinois, USA
	Funding: This material is based upon work sup- ported by the U.S. Department of Energy, Office of Sci- ence, Office of High Energy Physics under Award Num- ber DE-SC0011340. Proton accumulator rings and other circular hadron accelerators are susceptible to intensity- driven parametric instabilities because the zero-current charged particle dynamics are characterized by a single tune. Landau damping can suppress these instabilities, which requires energy spread in the beam or introducing nonlinear magnets such as octupoles. However, this approach reduces dynamic aperture. Nonlinear integrable optics can suppress parametric instabilities independent of energy spread in the distribution, while preserving the dynamic aperture. This novel approach promises to reduce particle losses and enable order-of-magnitude increases in beam intensity. In this paper we present results, obtained using the Lie operator formalism, on how chromaticity and dispersion affect particle orbits in integrable optics. We conclude that chromaticity in general breaks the integrability, unless the vertical and horizontal chromaticities are equal. Because of this, the chromaticity correcting magnets can be weaker and fewer correcting magnet families are required, thus minimizing the impact on dynamic aperture.
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MOPMA045	Conceptual Difficulties of a Thermodynamics Description of Charged-Particle Beams	emittance, space-charge, simulation, beam-transport	649
	S. Bernal UMD, College Park, Maryland, USA
	Funding: This work is funded by the US Dept. of Energy We review the existing phenomenological theories of emittance growth with and without entropy terms and re-examine the condition for thermal equipartitioning in an unbunched charged-particle beam. The model incorporates linear space charge and a uniform-focusing lattice. Because of non-extensitivity of the transverse ("thermal") energy and the absence of a classical heat bath, we conclude that a rigorous classical thermodynamics treatment of charged-particle beams is not possible. In particular, the postulated relationships between the rms emittance and temperature and entropy must be qualified.
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MOPMA047	Nonlinear Beam Dynamics Studies of the Next Generation Strong Focusing Cyclotrons as Compact High Brightness, Low Emittance Drivers	cavity, cyclotron, proton, wakefield	656
	S. Assadi, P.M. McIntyre, A. Sattarov Texas A&M University, College Station, Texas, USA N. Pogue PSI, Villigen, Villigen, Switzerland
	Funding: Work is partially supported by grants from the State of Texas (ASE) & the Michelle foundation. The Strong Focusing Cyclotron development at Texas A&M University has evolved from stacks of cyclotrons to a single layer high brightness, low emittance to produce greater than 10 mA of proton beam to a desired target at 800 MeV. The latest design has a major geometric design optimization of strong focusing quadrupoles and a modified algorithm of high gradient cavities to address the small turn separation, and interaction of radially neighboring bunches and reduced the number of turns necessary to reach the desired final energy under control conditions. In this paper, we present the new design, physics of nonlinear synchrobetratron coupling, mνh+nνv=p causing beam blow-up in other form of cyclotrons and how we have resolved it. The cavity beam loading and space charge effects of multi turns at low energies to reduce losses are discussed.
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MOPMA049	Development of a Single-pass Amplifier for an Optical Stochastic Cooling Proof-of-principle Experiment at Fermilab's IOTA facility	laser, undulator, experiment, radiation	659
	M.B. Andorf, P. Piot Northern Illinois University, DeKalb, Illinois, USA V.A. Lebedev, P. Piot Fermilab, Batavia, Illinois, USA
	Optical stochastic cooling (OSC) is a method of beam cooling which is expected to provide cooling rates orders of magnitude larger than ordinary stochastic cooling. Light from an undulator (the pickup) is amplified and fed back onto the particle beam via another undulator (the kicker). Fermilab is currently exploring a possible proof-of-principle experiment of the OSC at the integrable-optics test accelerator (IOTA) ring. To implement effective OSC a good correction of phase distortions in the entire band of the optical amplifier is required. In this contribution we present progress in experimental characterization of phase distortions associated to a Titanium Sapphire crystal laser-gain medium (a possible candidate gain medium for the OSC experiment to be performed at IOTA). We also discuss a possible option for a mid-IR amplifier.
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MOPMA058	Effect of Spherical Aberration on Beam Emittance Growth	emittance, space-charge, proton, simulation	688
	Y.K. Batygin LANL, Los Alamos, New Mexico, USA
	Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396 Spherical aberration in axial-symmetric magnetic focusing lenses results in S-shape figure of beam emittance. Filamentation of beam emittance in phase space is a fundamental property of a beam affected by aberrations. Analytical expression for effective beam emittance growth due to spherical aberration as a function of lens aberraion coefficient, initial beam emittance, beam radius, and focal lens of the focusing lens is obtained. Analysis is extended for beam space charge aberrations. Analytical results are confirmed by numerical calculations.
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MOPHA004	Oide Limit Mitigation Studies	radiation, quadrupole, luminosity, octupole	781
	O.R. Blanco-García, P. Bambade LAL, Orsay, France R. Tomás CERN, Geneva, Switzerland
	Particle radiation when traversing a focusing quadrupole limits the minimum achievable beam size, known as the Oide limit. This effect may be compensated by a pair of multipoles which reduce the impact of the energy loss in the vertical beam size. Simulations in PLACET using the CLIC 3 TeV QD0 and L⃰ show a reduction of (4.3 ± 0.2)% in the vertical beam size.
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TUYC3	Scaling Down Synchronous Acceleration: Recent Results, Current Status, and Future Plans of a Subrelativistic Dielectric Laser Acceleration Project	electron, laser, acceleration, experiment	1325
	J.C. McNeur, P. Hommelhoff, M. Kozak, A. Li, N. Schönenberger, A.D. Tafel University of Erlangen-Nuremberg, Erlangen, Germany
	This talk will describe the latest results using laser powered dielectric accelerators. Recent experiments in the US (SLAC) and Europe (MPQ) have fabricated dielectric accelerators powered with optical lasers and used them to accelerate electrons with gradients between 25 and 300 MeV/m. The latest results will be reviewed and prospects and applications for the future will be discussed.
	Slides TUYC3 [21.295 MB]
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TUPWA009	50 MeV Electron Linac with a RF Gun and a Thermoionic Cathode	gun, linac, cavity, cathode	1413
	A.S. Setty, A.S. Chauchat, D. Fasse, D. Jousse, P. Sirot Thales Communications & Security (TCS), Gennevilliers Cedex, France
	The low energy part of our pre injectors is made up of a 90 kV DC themoionic trioode gun, followed by a 500 MHz sub harmonic prebuncher and a 3 GHz prebuncher. We propose a new design for a 50 MeV linac with a RF gun . this study will compare the beam dynamics simulations for the new design and for our previous pre injectors. A. Setty et al. "Study of a RF gun with a Thermoionic Cathode", Proceeding IPAC 2014, Germany, Dresden, June 2014.
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TUPJE044	Local Orbit Response Matrix Measurement at SLS	quadrupole, optics, storage-ring, feedback	1713
	M. Aiba, M. Böge PSI, Villigen PSI, Switzerland
	The experimental determination of linear optics is essential to achieve a high performance ring accelerator. One of the methods, linear optics from closed orbits (LOCO), is widely employed to correct linear optics. Due to the ring nature, a quadrupole error at a location of the ring affects the entire orbit response measurement data. The orbit response, however, can be localised to a certain range of the ring when an orbit feedback (or correction) is applied to the rest of the ring. The quadrupole errors located in the range, where the feedback is acting, then have no impact, and the ring optics can be locally examined. An application of this technique to Swiss light source is discussed.
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TUPHA013	Skew-Quad Parametric-Resonance Ionization Cooling: Theory and Modeling	coupling, resonance, betatron, emittance	1993
	A. Afanasev GWU, Washington, USA Y.S. Derbenev, V.S. Morozov, A.V. Sy JLab, Newport News, Virginia, USA R.P. Johnson Muons, Inc, Illinois, USA
	Funding: This work was supported in part by U.S. DOE STTR Grants DE-SC0005589 and DE-SC0007634. Muon beam ionization cooling is a key component for the next generation of high-luminosity muon colliders. To reach adequately high luminosity without excessively large muon intensities, it was proposed previously to combine ionization cooling with techniques using a parametric resonance (PIC). Practical implementation of PIC proposal is a subject of this report. We show that an addition of skew quadrupoles to a planar PIC channel gives enough flexibility in the design to avoid unwanted resonances, while meeting the requirements of radially-periodic beam focusing at ionization-cooling plates, large dynamic aperture and an oscillating dispersion needed for aberration corrections. Theoretical arguments are corroborated with models and a detailed numerical analysis, providing step-by-step guidance for the design of Skew-quad PIC (SPIC) beamline.
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TUPWI044	Final Muon Emittance Exchange in Vacuum for a Collider	quadrupole, emittance, collider, betatron	2346
	D.J. Summers, J.G. Acosta, L.M. Cremaldi, T.L. Hart, S.J. Oliveros, L.P. Perera, W. Wu UMiss, University, Mississippi, USA D.V. Neuffer Fermilab, Batavia, Illinois, USA
	Funding: Work supported by NSF Award 0969770 We outline a plan for final muon ionization cooling with quadrupole doublets focusing onto short absorbers followed by emittance exchange in vacuum to achieve the small transverse beam sizes needed by a muon collider. A flat muon beam with a series of quadrupole doublet half cells appears to provide the strong focusing required for final cooling. Each quadrupole doublet has a low beta region occupied by a dense, low Z absorber. After final cooling, normalized xyz emittances of (0.071, 0.141, 2.4) mm-rad are exchanged into (0.025, 0.025, 70) mm-rad. Thin electrostatic septa efficiently slice the bunch into 17 parts. The 17 bunches are interleaved into a 3.7 meter long train with RF deflector cavities. Snap bunch coalescence combines the muon bunch train longitudinally in a 21 GeV ring in 55 microseconds, one quarter of a synchrotron oscillation period. A linear long wavelength RF bucket gives each bunch a different energy causing the bunches to drift until they merge into one bunch and can be captured in a short wavelength RF bucket with a 13% muon decay loss and a packing fraction as high as 87%.
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WEPJE015	Muon Tracking Studies in a Skew Parametric Resonance Ionization Cooling Channel	resonance, coupling, quadrupole, betatron	2705
	A.V. Sy, Y.S. Derbenev, V.S. Morozov JLab, Newport News, Virginia, USA A. Afanasev GWU, Washington, USA R.P. Johnson Muons, Inc, Illinois, USA
	Funding: This work was supported in part by U.S. DOE STTR Grant DE-SC0005589. This manuscript has been authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Skew Parametric-resonance Ionization Cooling (SPIC) is an extension of the Parametric-resonance Ionization Cooling (PIC) framework that has previously been explored as the final 6D cooling stage of a high-luminosity muon collider. The addition of skew quadrupoles to the PIC magnetic focusing channel induces coupled dynamic behavior of the beam that is radially periodic. The periodicity of the radial motion allows for the avoidance of unwanted resonances in the horizontal and vertical transverse planes, while still providing periodic locations at which ionization cooling components can be implemented. A first practical implementation of the magnetic field components required in the SPIC channel is modeled in MADX. Dynamic features of the coupled correlated optics with and without induced parametric resonance are presented and discussed.
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WEPMA038	Compact In-vacuum Quadrupoles for a Beam Transport System at a Laser Wakefield Accelerator	vacuum, quadrupole, operation, laser	2845
	A. Bernhard, V. Afonso Rodríguez, A.-S. Müller, J. Senger, W. Werner, C. Widmann KIT, Karlsruhe, Germany
	Funding: This work is partially funded by the German Federal Ministry for Education and Research under contract no. 05K10VK2 and 05K10SJ2. For the transport and matching of electrons generated by a Laser Wakefield Accelerator (LWFA) a beam transport system with strong focusing magnets and a compact design is required. For the realization of such a beam transport system at the LWFA in Jena, Germany, two small series of inexpensive, modular quadrupoles were designed and built. The quadrupoles are iron-dominated electromagnets in order to keep the transport system adaptable to different energies and target parameters. To achieve the required field strength it was necessary to choose a small magnetic aperture. Therefore the magnets were designed for in-vacuum use with water-cooled coils. In this contribution the design, the realization and first field measurements of these quadrupoles are presented.
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WEPMN057	Calculation and Design of a RF Cavity for a Novel Compact Superconducting Cyclotron for Radioisotope Production	cavity, cyclotron, simulation, ion	3055
	D. Gavela, J. Calero, L. García-Tabarés, A. Guirao, D. Obradors-Campos, C. Oliver, J.M. Pérez Morales, I. Podadera, F. Toral CIEMAT, Madrid, Spain
	Funding: Work partially funded by CDTI and the Spanish Ministry of Economy and Competitiveness, under the subprogram CENIT, project AMIT, reference CEN-20101014 The AMIT cyclotron will be a 8.5 MeV, 10 microAmp, CW, H⁻ accelerator for the purpose of radioisotope production. It includes a superconducting, weak focusing, 4 T magnet, which allows for a low extraction radius and a compact design. The RF cavity design has to deal with challenging requirements: high electric fields created by the required accelerating voltage (60 kV – 70 kV) on a small gap, a small aperture of the magnet leading to high capacitances and thermal losses, and a requirement for a low overall size of the cavity. A quarter wave resonator with one dee (two acceleration gaps) design was chosen. Calculations with HFSS have been performed to compute the resonant frequency, tuners sensitivity, S-parameters, power losses and geometry for input coupler and pickup. A structural Ansys model has been used to analyze the stresses and the deformations of the cavity. A thermal Ansys model was used for the design of the cooling circuits and the calculation of the temperature distribution. Finally, the fluid dynamics of the cooling circuits have been carefully studied. The results of these calculations and the consequent design decisions are presented in this paper.
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THPF047	New Series of RFQ Vane Shapes	acceleration, multipole, quadrupole, rfq	3808
	Y. Iwashita, Y. Fuwa Kyoto ICR, Uji, Kyoto, Japan
	New series of RFQ vane shapes are under investigation by introducing more terms in addition to the two term potential. Because they can incorporate with the feature of the trapezoidal shape modulation with less multipole components, higher acceleration efficiency is expected. The simulation study will be presented.
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THPF060	The Simulation Study of Space Charge Effects for CSNS Linac	emittance, space-charge, DTL, simulation	3833
	Y. Yuan, L. Huang, J. Peng, S. Wang IHEP, Beijing, People's Republic of China
	China Spallation Neutron Source (CSNS) is a high intensity accelerator based facility. Its accelerator consists of an H⁻ injector and a proton Rapid Cycling Synchrotron. The injector includes the front end and linac. The RFQ accelerates the beam to 3MeV, and then DTL accelerates it to 80MeV. The space charge effect is the most important cause of emittance growth and beam loss due to the low beam energy and the high peak current. The paper performed simulation studies on the space charge effects at the LINAC by using three-dimensional code IMPACT-Z. The emittance evolution is studied in the point of view of the singe-particle dynamics and multi-particle dynamics with different peak beam current. The effect of mismatch is studied by simulation, and the emittance growth with different mismatch factor are given.
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THPF078	Effect of the Field Maps on the Beam Dynamics of the ESS Drift Tube Linac	emittance, DTL, klystron, linac	3864
	R. De Prisco, M. Eshraqi, Y.I. Levinsen, R. Miyamoto, E. Sargsyan ESS, Lund, Sweden A.R. Karlsson Lund University, Lund, Sweden
	In the beam dynamic design and modelling of the European Spallation Source (ESS) Drift Tube Linac (DTL) simplified models have been used for the focusing and accelerating structures. Since the high current requires precise control of the beam to minimise the losses it is useful to analyse the beam dynamics by using accurate field maps of the focusing and accelerating structures. In this paper the effects of the 3D-field maps on the beam dynamics of the ESS DTL are presented.
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THPF081	On the Suitability of a Solenoid Horn for the ESS Neutrino Superbeam	solenoid, target, linac, detector	3873
	M. Olvegård, T.J.C. Ekelöf, R.J.M.Y. Ruber, V.G. Ziemann Uppsala University, Uppsala, Sweden J.-P. Koutchouk CERN, Geneva, Switzerland
	The European Spallation Source (ESS), now under construction in Lund, Sweden, offers unique opportunities for experimental physics, not only in neutron science but potentially in particle physics. The ESS neutrino superbeam project plans to use a 5 MW proton beam from the ESS linac to generate a high intensity neutrino superbeam, with the final goal of detecting leptonic CP-violation in an underground megaton Cherenkov water detector. The neutrino production requires a second target station and a complex focusing system for the pions emerging from the target. The normal-conducting magnetic horns that are normally used for these applications cannot accept the 2.86 ms long proton pulses of the ESS linac, which means that pulse shortening in an accumulator ring would be required. That, in turn, requires H⁻ operation in the linac to accommodate the high intensity. As an attractive alternative, we investigate the possibility of using superconducting solenoids for the pion focusing. This solenoid horn system needs to also separate positive and negative pion charge as completely as possible, in order to generate separately neutrino and anti-neutrino beams. We present here progress in the study of such a solenoid horn.
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THPF135	Optimization of Orbits, SRF Acceleration, and Focusing Lattice for a Strong-Focusing Cyclotron	cavity, cyclotron, dipole, SRF	4038
	K.E. Melconian, S. Assadi, J. Gerity, J.N. Kellams, P.M. McIntyre, A. Sattarov Texas A&M University, College Station, Texas, USA N. Pogue PSI, Villigen, Villigen, Switzerland
	The strong-focusing cyclotron is a high-current proton/ion accelerator in which superconducting rf cavities are used to provide enough energy gain per turn to fully separate orbits, and arc-shaped beam transport channels are located in the sector dipole aperture to provide strong focusing of all orbits. An optimization method has been devised by which the orbit separations can be adjusted to provide sufficient separation while maintaining isochronicity on all orbits. The transport optics of the FD lattice is also optimized to provide stable transport and to lock the betatron tunes to a favorable value over the full range of acceleration.
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THPF139	Nonlinear Optics of Solenoid Magnets	solenoid, lattice, optics, factory	4048
	S.M. Lund FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Grant No. PHY-1102511. Solenoid magnets are often employed for focusing in low energy beam transport lattices in the front-end of a machine. We derive a relatively simple analytic formula for the nonlinear angular focusing kick imparted to particles traversing the solenoid. Few approximations are made. The formula suggests that for beam transport, little can be done to reduce nonlinearities in solenoid-type magnets other than take a simple design without abrupt changes as a function of axial coordinate and appropriately choose the aspect ratio (characteristic bore radius over axial length) of the magnet system and the beam filling factor within the aperture to limit nonlinear effects. Illustrative applications of the formula characterize nonlinear focusing effects in iron-free and iron type solenoid magnets.
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THPF140	Unique Accelerator Integration Features of the Heavy Ion CW Driver Linac at FRIB	linac, proton, beam-loading, solenoid	4051
	Y. Yamazaki, N.K. Bultman, A. Facco, M. Ikegami, F. Marti, G. Pozdeyev, J. Wei, Y. Zhang, Q. Zhao FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 The FRIB driver linac is a front runner for the future high power hadron linacs, making a full use of CW, superconducting acceleration from very low β. Accelerator Driven Nuclear Waste Transmutation System (ADS), International Fusion Material Irradiation Facility (IFMIF), Project-X type proton accelerators for high energy physics and others may utilize the technologies developed for the design, construction, commissioning and power ramp up of the FRIB linac. Although each technology has been already well developed individually (except for charge stripper), their integration is another challenge. In addition, extremely high Bragg peak of uranium beams (several thousand times as high as that of proton beams) gives rise to one of the biggest challenges in many aspects. This report summarizes these challenges and their mitigations, emphasizing the commonly overlooked features.
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Paper

Title

Other Keywords

Page

MOPWA037

Mirror Symmetric Chicane-Type Emittance Exchange Beamline with Two Deflecting Cavities

quadrupole, emittance, cavity, dipole

190

V. Balandin, W. Decking, N. Golubeva
DESY, Hamburg, Germany

Among optical systems for transverse-to-longitudinal emittance exchange (EEX) chicane-type beamlines are of keen interest, because they do not alter the beam propagation direction. Several designs of such beamlines involving a single dipole-mode cavity (TDC) are known. In this paper we present a chicane-type EEX beamline utilizing two TDCs instead of one. The advantages of this beamline are that it is mirror symmetric and does not require an additional accelerating mode cavity for compensation of the so-called thick-lens effect, and, in the compact design, it allows better control of the beam focusing in the non-bending plane than known beamlines with one TDC.

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MOPWA038

Sensitivity of Linac Optics to Focusing and Energy Errors

optics, linac, operation, quadrupole

193

V. Balandin, W. Decking, N. Golubeva
DESY, Hamburg, Germany

The ability to control beam optics in the presence of such imperfections as focusing and energy gain errors is essential for a successful operation of high brightness electron linacs providing beams for free-electron lasers. We characterize the cumulative effect of these imperfections using the value of mismatch parameter calculated at the linac exit and show how it depends on the design of the focusing lattice.

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MOPJE023

3D Computer Simulations of the Ultrarelativistic Beam Dynamics in Super Colliders

simulation, collider, experiment, plasma

326

M.A. Boronina, V.A. Vshivkov
ICM&MG SB RAS, Novosibirsk, Russia
G. Dudnikova
ICT SB RAS, Novosibirsk, Russia

Funding: The work is supported by RFBR Grants 14-01-31088, 14-01-00392, 14-07-00241.
The problem of numerical modeling of beam-beam interaction with high relativistic factor (~10⁴) is considered. We present 3D a self-consistent simulation model based on particle-in-cell method. The mixed Euler-Lagrangian decomposition is used in parallel algorithm for achieving good load balancing and reducing communication cost. Stable regimes of beam dynamics, depending on the beams configuration (beta-function, emittance, energy, currents and relative offset) can be found on the base of the model. In the calculations we used 10⁸ particles on the grid 100x100x100, the number of processors depends highly on the beam shape. The Lomonosov Super Computer and Siberian Supercomputer Centre cluster were used to perform the presented simulations.

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MOPJE043

Design and Optimization of Electrostatic Deflectors for ELENA

vacuum, antiproton, alignment, simulation

382

D. Barna
University of Tokyo, Tokyo, Japan
W. Bartmann, M.A. Fraser, R. Ostojić
CERN, Geneva, Switzerland

The ELENA ring will decelerate the antiprotons ejected from the Antiproton Decelerator (AD) at 5.3 MeV down to 100 keV kinetic energy. The slow antiprotons will be delivered to experiments using electrostatic beamlines, consisting of quadrupoles, correctors and deflectors. An extensive simulation study was carried out to find solutions to minimize the aberrations of the deflectors. These solutions will be presented together with the actual design of these devices.

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MOPJE084

Particle-in-cell Simulations of a Plasma Lens at Daresbury Laboratory

plasma, emittance, simulation, experiment

518

K. Hanahoe, O. Mete, G.X. Xia
UMAN, Manchester, United Kingdom
D. Angal-Kalinin, J.K. Jones
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
J.D.A. Smith
TXUK, Warrington, United Kingdom

Feasibility of a focusing element using the transverse fields provided by a plasma cell was studied numerically. In this paper, an experimental set up is proposed for various beam parameters available from the VELA and CLARA beam lines at Daresbury Laboratory. 2D simulation results from VSim, and expected results from planned measurement stations are presented. Field properties and the advantages and disadvantages of such an instrument compared to conventional focusing elements are discussed.

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MOPMA016

Coupler RF Kick in the Input 1.3 GHz Accelerating Cavity of the LCLS-II Linac

cavity, HOM, accelerating-gradient, emittance

571

A. Lunin, N. Solyak, A.I. Sukhanov, V.P. Yakovlev
Fermilab, Batavia, Illinois, USA

Main and HOM couplers break the cavity axial symmetry, distort RF field and, thus, create a transverse kick, even for a particle moving along the cavity axes. Dependence of a kick on the RF phase causes a beam emittance dilution and degrade the FEL radiation quality. The transverse kick is most dangerous for a beam passing through the first accelerating structure of a linac, where particles energy and their relativistic mass are low. In the paper we analyze the coupler RF kick in the first accelerating structure of the LCSL-II linac.

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MOPMA028

Chromaticity and Dispersion in Nonlinear Integrable Optics

lattice, optics, dynamic-aperture, octupole

608

S.D. Webb, D.L. Bruhwiler
RadiaSoft LLC, Boulder, Colorado, USA
V.V. Danilov
ORNL, Oak Ridge, Tennessee, USA
S. Nagaitsev, A. Valishev
Fermilab, Batavia, Illinois, USA

Funding: This material is based upon work sup- ported by the U.S. Department of Energy, Office of Sci- ence, Office of High Energy Physics under Award Num- ber DE-SC0011340.
Proton accumulator rings and other circular hadron accelerators are susceptible to intensity- driven parametric instabilities because the zero-current charged particle dynamics are characterized by a single tune. Landau damping can suppress these instabilities, which requires energy spread in the beam or introducing nonlinear magnets such as octupoles. However, this approach reduces dynamic aperture. Nonlinear integrable optics can suppress parametric instabilities independent of energy spread in the distribution, while preserving the dynamic aperture. This novel approach promises to reduce particle losses and enable order-of-magnitude increases in beam intensity. In this paper we present results, obtained using the Lie operator formalism, on how chromaticity and dispersion affect particle orbits in integrable optics. We conclude that chromaticity in general breaks the integrability, unless the vertical and horizontal chromaticities are equal. Because of this, the chromaticity correcting magnets can be weaker and fewer correcting magnet families are required, thus minimizing the impact on dynamic aperture.

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MOPMA045

Conceptual Difficulties of a Thermodynamics Description of Charged-Particle Beams

emittance, space-charge, simulation, beam-transport

649

S. Bernal
UMD, College Park, Maryland, USA

Funding: This work is funded by the US Dept. of Energy
We review the existing phenomenological theories of emittance growth with and without entropy terms and re-examine the condition for thermal equipartitioning in an unbunched charged-particle beam. The model incorporates linear space charge and a uniform-focusing lattice. Because of non-extensitivity of the transverse ("thermal") energy and the absence of a classical heat bath, we conclude that a rigorous classical thermodynamics treatment of charged-particle beams is not possible. In particular, the postulated relationships between the rms emittance and temperature and entropy must be qualified.

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MOPMA047

Nonlinear Beam Dynamics Studies of the Next Generation Strong Focusing Cyclotrons as Compact High Brightness, Low Emittance Drivers

cavity, cyclotron, proton, wakefield

656

S. Assadi, P.M. McIntyre, A. Sattarov
Texas A&M University, College Station, Texas, USA
N. Pogue
PSI, Villigen, Villigen, Switzerland

Funding: Work is partially supported by grants from the State of Texas (ASE) & the Michelle foundation.
The Strong Focusing Cyclotron development at Texas A&M University has evolved from stacks of cyclotrons to a single layer high brightness, low emittance to produce greater than 10 mA of proton beam to a desired target at 800 MeV. The latest design has a major geometric design optimization of strong focusing quadrupoles and a modified algorithm of high gradient cavities to address the small turn separation, and interaction of radially neighboring bunches and reduced the number of turns necessary to reach the desired final energy under control conditions. In this paper, we present the new design, physics of nonlinear synchrobetratron coupling, mνh+nνv=p causing beam blow-up in other form of cyclotrons and how we have resolved it. The cavity beam loading and space charge effects of multi turns at low energies to reduce losses are discussed.

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MOPMA049

Development of a Single-pass Amplifier for an Optical Stochastic Cooling Proof-of-principle Experiment at Fermilab's IOTA facility

laser, undulator, experiment, radiation

659

M.B. Andorf, P. Piot
Northern Illinois University, DeKalb, Illinois, USA
V.A. Lebedev, P. Piot
Fermilab, Batavia, Illinois, USA

Optical stochastic cooling (OSC) is a method of beam cooling which is expected to provide cooling rates orders of magnitude larger than ordinary stochastic cooling. Light from an undulator (the pickup) is amplified and fed back onto the particle beam via another undulator (the kicker). Fermilab is currently exploring a possible proof-of-principle experiment of the OSC at the integrable-optics test accelerator (IOTA) ring. To implement effective OSC a good correction of phase distortions in the entire band of the optical amplifier is required. In this contribution we present progress in experimental characterization of phase distortions associated to a Titanium Sapphire crystal laser-gain medium (a possible candidate gain medium for the OSC experiment to be performed at IOTA). We also discuss a possible option for a mid-IR amplifier.

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MOPMA058

Effect of Spherical Aberration on Beam Emittance Growth

emittance, space-charge, proton, simulation

688

Y.K. Batygin
LANL, Los Alamos, New Mexico, USA

Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
Spherical aberration in axial-symmetric magnetic focusing lenses results in S-shape figure of beam emittance. Filamentation of beam emittance in phase space is a fundamental property of a beam affected by aberrations. Analytical expression for effective beam emittance growth due to spherical aberration as a function of lens aberraion coefficient, initial beam emittance, beam radius, and focal lens of the focusing lens is obtained. Analysis is extended for beam space charge aberrations. Analytical results are confirmed by numerical calculations.

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MOPHA004

Oide Limit Mitigation Studies

radiation, quadrupole, luminosity, octupole

781

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

Particle radiation when traversing a focusing quadrupole limits the minimum achievable beam size, known as the Oide limit. This effect may be compensated by a pair of multipoles which reduce the impact of the energy loss in the vertical beam size. Simulations in PLACET using the CLIC 3 TeV QD0 and L⃰ show a reduction of (4.3 ± 0.2)% in the vertical beam size.

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TUYC3

Scaling Down Synchronous Acceleration: Recent Results, Current Status, and Future Plans of a Subrelativistic Dielectric Laser Acceleration Project

electron, laser, acceleration, experiment

1325

J.C. McNeur, P. Hommelhoff, M. Kozak, A. Li, N. Schönenberger, A.D. Tafel
University of Erlangen-Nuremberg, Erlangen, Germany

This talk will describe the latest results using laser powered dielectric accelerators. Recent experiments in the US (SLAC) and Europe (MPQ) have fabricated dielectric accelerators powered with optical lasers and used them to accelerate electrons with gradients between 25 and 300 MeV/m. The latest results will be reviewed and prospects and applications for the future will be discussed.

Slides TUYC3 [21.295 MB]

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TUPWA009

50 MeV Electron Linac with a RF Gun and a Thermoionic Cathode

gun, linac, cavity, cathode

1413

A.S. Setty, A.S. Chauchat, D. Fasse, D. Jousse, P. Sirot
Thales Communications & Security (TCS), Gennevilliers Cedex, France

The low energy part of our pre injectors is made up of a 90 kV DC themoionic trioode gun, followed by a 500 MHz sub harmonic prebuncher and a 3 GHz prebuncher. We propose a new design for a 50 MeV linac with a RF gun *. this study will compare the beam dynamics simulations for the new design and for our previous pre injectors.
* A. Setty et al. "Study of a RF gun with a Thermoionic Cathode", Proceeding IPAC 2014, Germany, Dresden, June 2014.

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TUPJE044

Local Orbit Response Matrix Measurement at SLS

quadrupole, optics, storage-ring, feedback

1713

M. Aiba, M. Böge
PSI, Villigen PSI, Switzerland

The experimental determination of linear optics is essential to achieve a high performance ring accelerator. One of the methods, linear optics from closed orbits (LOCO), is widely employed to correct linear optics. Due to the ring nature, a quadrupole error at a location of the ring affects the entire orbit response measurement data. The orbit response, however, can be localised to a certain range of the ring when an orbit feedback (or correction) is applied to the rest of the ring. The quadrupole errors located in the range, where the feedback is acting, then have no impact, and the ring optics can be locally examined. An application of this technique to Swiss light source is discussed.

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TUPHA013

Skew-Quad Parametric-Resonance Ionization Cooling: Theory and Modeling

coupling, resonance, betatron, emittance

1993

A. Afanasev
GWU, Washington, USA
Y.S. Derbenev, V.S. Morozov, A.V. Sy
JLab, Newport News, Virginia, USA
R.P. Johnson
Muons, Inc, Illinois, USA

Funding: This work was supported in part by U.S. DOE STTR Grants DE-SC0005589 and DE-SC0007634.
Muon beam ionization cooling is a key component for the next generation of high-luminosity muon colliders. To reach adequately high luminosity without excessively large muon intensities, it was proposed previously to combine ionization cooling with techniques using a parametric resonance (PIC). Practical implementation of PIC proposal is a subject of this report. We show that an addition of skew quadrupoles to a planar PIC channel gives enough flexibility in the design to avoid unwanted resonances, while meeting the requirements of radially-periodic beam focusing at ionization-cooling plates, large dynamic aperture and an oscillating dispersion needed for aberration corrections. Theoretical arguments are corroborated with models and a detailed numerical analysis, providing step-by-step guidance for the design of Skew-quad PIC (SPIC) beamline.

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TUPWI044

Final Muon Emittance Exchange in Vacuum for a Collider

quadrupole, emittance, collider, betatron

2346

D.J. Summers, J.G. Acosta, L.M. Cremaldi, T.L. Hart, S.J. Oliveros, L.P. Perera, W. Wu
UMiss, University, Mississippi, USA
D.V. Neuffer
Fermilab, Batavia, Illinois, USA

Funding: Work supported by NSF Award 0969770
We outline a plan for final muon ionization cooling with quadrupole doublets focusing onto short absorbers followed by emittance exchange in vacuum to achieve the small transverse beam sizes needed by a muon collider. A flat muon beam with a series of quadrupole doublet half cells appears to provide the strong focusing required for final cooling. Each quadrupole doublet has a low beta region occupied by a dense, low Z absorber. After final cooling, normalized xyz emittances of (0.071, 0.141, 2.4) mm-rad are exchanged into (0.025, 0.025, 70) mm-rad. Thin electrostatic septa efficiently slice the bunch into 17 parts. The 17 bunches are interleaved into a 3.7 meter long train with RF deflector cavities. Snap bunch coalescence combines the muon bunch train longitudinally in a 21 GeV ring in 55 microseconds, one quarter of a synchrotron oscillation period. A linear long wavelength RF bucket gives each bunch a different energy causing the bunches to drift until they merge into one bunch and can be captured in a short wavelength RF bucket with a 13% muon decay loss and a packing fraction as high as 87%.

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WEPJE015

Muon Tracking Studies in a Skew Parametric Resonance Ionization Cooling Channel

resonance, coupling, quadrupole, betatron

2705

A.V. Sy, Y.S. Derbenev, V.S. Morozov
JLab, Newport News, Virginia, USA
A. Afanasev
GWU, Washington, USA
R.P. Johnson
Muons, Inc, Illinois, USA

Funding: This work was supported in part by U.S. DOE STTR Grant DE-SC0005589. This manuscript has been authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Skew Parametric-resonance Ionization Cooling (SPIC) is an extension of the Parametric-resonance Ionization Cooling (PIC) framework that has previously been explored as the final 6D cooling stage of a high-luminosity muon collider. The addition of skew quadrupoles to the PIC magnetic focusing channel induces coupled dynamic behavior of the beam that is radially periodic. The periodicity of the radial motion allows for the avoidance of unwanted resonances in the horizontal and vertical transverse planes, while still providing periodic locations at which ionization cooling components can be implemented. A first practical implementation of the magnetic field components required in the SPIC channel is modeled in MADX. Dynamic features of the coupled correlated optics with and without induced parametric resonance are presented and discussed.

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WEPMA038

Compact In-vacuum Quadrupoles for a Beam Transport System at a Laser Wakefield Accelerator

vacuum, quadrupole, operation, laser

2845

A. Bernhard, V. Afonso Rodríguez, A.-S. Müller, J. Senger, W. Werner, C. Widmann
KIT, Karlsruhe, Germany

Funding: This work is partially funded by the German Federal Ministry for Education and Research under contract no. 05K10VK2 and 05K10SJ2.
For the transport and matching of electrons generated by a Laser Wakefield Accelerator (LWFA) a beam transport system with strong focusing magnets and a compact design is required. For the realization of such a beam transport system at the LWFA in Jena, Germany, two small series of inexpensive, modular quadrupoles were designed and built. The quadrupoles are iron-dominated electromagnets in order to keep the transport system adaptable to different energies and target parameters. To achieve the required field strength it was necessary to choose a small magnetic aperture. Therefore the magnets were designed for in-vacuum use with water-cooled coils. In this contribution the design, the realization and first field measurements of these quadrupoles are presented.

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WEPMN057

Calculation and Design of a RF Cavity for a Novel Compact Superconducting Cyclotron for Radioisotope Production

cavity, cyclotron, simulation, ion

3055

D. Gavela, J. Calero, L. García-Tabarés, A. Guirao, D. Obradors-Campos, C. Oliver, J.M. Pérez Morales, I. Podadera, F. Toral
CIEMAT, Madrid, Spain

Funding: Work partially funded by CDTI and the Spanish Ministry of Economy and Competitiveness, under the subprogram CENIT, project AMIT, reference CEN-20101014
The AMIT cyclotron will be a 8.5 MeV, 10 microAmp, CW, H⁻ accelerator for the purpose of radioisotope production. It includes a superconducting, weak focusing, 4 T magnet, which allows for a low extraction radius and a compact design. The RF cavity design has to deal with challenging requirements: high electric fields created by the required accelerating voltage (60 kV – 70 kV) on a small gap, a small aperture of the magnet leading to high capacitances and thermal losses, and a requirement for a low overall size of the cavity. A quarter wave resonator with one dee (two acceleration gaps) design was chosen. Calculations with HFSS have been performed to compute the resonant frequency, tuners sensitivity, S-parameters, power losses and geometry for input coupler and pickup. A structural Ansys model has been used to analyze the stresses and the deformations of the cavity. A thermal Ansys model was used for the design of the cooling circuits and the calculation of the temperature distribution. Finally, the fluid dynamics of the cooling circuits have been carefully studied. The results of these calculations and the consequent design decisions are presented in this paper.

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THPF047

New Series of RFQ Vane Shapes

acceleration, multipole, quadrupole, rfq

3808

Y. Iwashita, Y. Fuwa
Kyoto ICR, Uji, Kyoto, Japan

New series of RFQ vane shapes are under investigation by introducing more terms in addition to the two term potential. Because they can incorporate with the feature of the trapezoidal shape modulation with less multipole components, higher acceleration efficiency is expected. The simulation study will be presented.

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THPF060

The Simulation Study of Space Charge Effects for CSNS Linac

emittance, space-charge, DTL, simulation

3833

Y. Yuan, L. Huang, J. Peng, S. Wang
IHEP, Beijing, People's Republic of China

China Spallation Neutron Source (CSNS) is a high intensity accelerator based facility. Its accelerator consists of an H⁻ injector and a proton Rapid Cycling Synchrotron. The injector includes the front end and linac. The RFQ accelerates the beam to 3MeV, and then DTL accelerates it to 80MeV. The space charge effect is the most important cause of emittance growth and beam loss due to the low beam energy and the high peak current. The paper performed simulation studies on the space charge effects at the LINAC by using three-dimensional code IMPACT-Z. The emittance evolution is studied in the point of view of the singe-particle dynamics and multi-particle dynamics with different peak beam current. The effect of mismatch is studied by simulation, and the emittance growth with different mismatch factor are given.

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THPF078

Effect of the Field Maps on the Beam Dynamics of the ESS Drift Tube Linac

emittance, DTL, klystron, linac

3864

R. De Prisco, M. Eshraqi, Y.I. Levinsen, R. Miyamoto, E. Sargsyan
ESS, Lund, Sweden
A.R. Karlsson
Lund University, Lund, Sweden

In the beam dynamic design and modelling of the European Spallation Source (ESS) Drift Tube Linac (DTL) simplified models have been used for the focusing and accelerating structures. Since the high current requires precise control of the beam to minimise the losses it is useful to analyse the beam dynamics by using accurate field maps of the focusing and accelerating structures. In this paper the effects of the 3D-field maps on the beam dynamics of the ESS DTL are presented.

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THPF081

On the Suitability of a Solenoid Horn for the ESS Neutrino Superbeam

solenoid, target, linac, detector

3873

M. Olvegård, T.J.C. Ekelöf, R.J.M.Y. Ruber, V.G. Ziemann
Uppsala University, Uppsala, Sweden
J.-P. Koutchouk
CERN, Geneva, Switzerland

The European Spallation Source (ESS), now under construction in Lund, Sweden, offers unique opportunities for experimental physics, not only in neutron science but potentially in particle physics. The ESS neutrino superbeam project plans to use a 5 MW proton beam from the ESS linac to generate a high intensity neutrino superbeam, with the final goal of detecting leptonic CP-violation in an underground megaton Cherenkov water detector. The neutrino production requires a second target station and a complex focusing system for the pions emerging from the target. The normal-conducting magnetic horns that are normally used for these applications cannot accept the 2.86 ms long proton pulses of the ESS linac, which means that pulse shortening in an accumulator ring would be required. That, in turn, requires H⁻ operation in the linac to accommodate the high intensity. As an attractive alternative, we investigate the possibility of using superconducting solenoids for the pion focusing. This solenoid horn system needs to also separate positive and negative pion charge as completely as possible, in order to generate separately neutrino and anti-neutrino beams. We present here progress in the study of such a solenoid horn.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF081

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THPF135

Optimization of Orbits, SRF Acceleration, and Focusing Lattice for a Strong-Focusing Cyclotron

cavity, cyclotron, dipole, SRF

4038

K.E. Melconian, S. Assadi, J. Gerity, J.N. Kellams, P.M. McIntyre, A. Sattarov
Texas A&M University, College Station, Texas, USA
N. Pogue
PSI, Villigen, Villigen, Switzerland

The strong-focusing cyclotron is a high-current proton/ion accelerator in which superconducting rf cavities are used to provide enough energy gain per turn to fully separate orbits, and arc-shaped beam transport channels are located in the sector dipole aperture to provide strong focusing of all orbits. An optimization method has been devised by which the orbit separations can be adjusted to provide sufficient separation while maintaining isochronicity on all orbits. The transport optics of the FD lattice is also optimized to provide stable transport and to lock the betatron tunes to a favorable value over the full range of acceleration.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF135

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THPF139

Nonlinear Optics of Solenoid Magnets

solenoid, lattice, optics, factory

4048

S.M. Lund
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Grant No. PHY-1102511.
Solenoid magnets are often employed for focusing in low energy beam transport lattices in the front-end of a machine. We derive a relatively simple analytic formula for the nonlinear angular focusing kick imparted to particles traversing the solenoid. Few approximations are made. The formula suggests that for beam transport, little can be done to reduce nonlinearities in solenoid-type magnets other than take a simple design without abrupt changes as a function of axial coordinate and appropriately choose the aspect ratio (characteristic bore radius over axial length) of the magnet system and the beam filling factor within the aperture to limit nonlinear effects. Illustrative applications of the formula characterize nonlinear focusing effects in iron-free and iron type solenoid magnets.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF139

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THPF140

Unique Accelerator Integration Features of the Heavy Ion CW Driver Linac at FRIB

linac, proton, beam-loading, solenoid

4051

Y. Yamazaki, N.K. Bultman, A. Facco, M. Ikegami, F. Marti, G. Pozdeyev, J. Wei, Y. Zhang, Q. Zhao
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The FRIB driver linac is a front runner for the future high power hadron linacs, making a full use of CW, superconducting acceleration from very low β. Accelerator Driven Nuclear Waste Transmutation System (ADS), International Fusion Material Irradiation Facility (IFMIF), Project-X type proton accelerators for high energy physics and others may utilize the technologies developed for the design, construction, commissioning and power ramp up of the FRIB linac. Although each technology has been already well developed individually (except for charge stripper), their integration is another challenge. In addition, extremely high Bragg peak of uranium beams (several thousand times as high as that of proton beams) gives rise to one of the biggest challenges in many aspects. This report summarizes these challenges and their mitigations, emphasizing the commonly overlooked features.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF140

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