IPAC2015 - List of Keywords (dynamic-aperture)

Paper	Title	Other Keywords	Page
MOPWA019	Status of the Robinson Wiggler Project at the Metrology Light Source	wiggler, dipole, radiation, damping	132
	T. Goetsch, J. Feikes, M. Ries, G. Wüstefeld HZB, Berlin, Germany
	The beam lifetime in electron storage rings concerns machines running in decay mode as well as machines doing top-up. A standard procedure to increase the lifetime is via bunch lengthening as the lifetime depends on the electron density in the bunch. Bunch lengthening is typically achieved with higher harmonic (Landau) cavities. As noted in , there are several advantages in using a different approach: it is possible to increase the bunch length by installing a Transverse Gradient (Robinson) Wiggler, which allows to transfer damping between the horizontal and the longitudinal plane. While increasing the bunch length, the horizontal emittance is being reduced yielding advantages regarding the source size depending on the magnet optics. At the Metrology Light Source, a primary source standard used by Germanys national metrology institute (Physikalisch-Technische Bundesanstalt), such a scheme is being investigated. The current state of the project including dynamic aperture effects and synchrotron radiation issues of the device is being presented in the following. T. Goetsch et al.,WEPRO028 in Proceedings of IPAC2014, Dresden (Germany), 2014 ** R. Klein et al., Phys. Rev. ST-AB 11, 110701, 2008
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MOPJE009	Lattice Design of the SSRF-U Storage Ring	emittance, storage-ring, lattice, injection	304
	S.Q. Tian, B.C. Jiang, M.Z. Zhang, Q.L. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	Multi-Bend Achromatic (MBA) cell has been well known to significantly reduce the beam emittance of the synchrotron radiation light sources in the past two decades. With the great development of the high gradient magnets, the small-aperture vacuum chamber and the precise alignment, the ultimate-emittance ring based on MBA lattice became practical in recent years. We present a preliminary lattice design for the upgraded SSRF storage ring based on a 7BA lattice in this paper. The circumference and the number of the straight sections are preserved for the existing tunnel. The beam energy is reduced to 3 GeV, and the beam emittance is reduced to about 200 pm.rad. The optimized dynamic aperture is about 10 mm in the horizontal plane, and a sufficient beam injection based on the closed orbit bump can be implemented.
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MOPJE015	Compensations of the DEPU Effects at the SSRF Storage Ring	quadrupole, coupling, injection, sextupole	307
	M.Z. Zhang, B.C. Jiang, J.H. Tan, S.Q. Tian, M. Zhang, Q.L. Zhang SINAP, Shanghai, People's Republic of China
	A paired APPLE-II type Ellipsoid Polarized Undulator（DEPU）has been installed in the SSRF storage ring which can be mechanically switched between two undulators with difference period length. One of them get notable effects on the optics including CODs, tune, coupling and dynamic aperture. We report in this paper, feed forward tables of correctors, quadrupoles and skew quarupoles are used for the optics correction and sextupole optimization is used for the dynamic aperture recovery.
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MOPJE079	Tracking Studies in the LHeC Lattice	lattice, resonance, proton, electron	502
	E. Cruz Alaniz, D. Newton The University of Liverpool, Liverpool, United Kingdom E. Cruz Alaniz, D. Newton Cockcroft Institute, Warrington, Cheshire, United Kingdom R. Tomás CERN, Geneva, Switzerland
	Funding: This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289485 The Large Hadron Electron Collider (LHeC) is a proposed upgrade of the LHC to provide electron-proton collisions and explore a new regime of energy and luminosity for nucleon-lepton scattering. A nominal design has previously been presented, featuring a lattice and optical configuration to focus one of the proton beams of the LHC (reaching a value of β^=10 cm) and to collide it head-on with an electron beam to produce collisions with the desired luminosity of L=10³³ cm^-2 s^-1. The proton beam optics is achieved with the aid of a new inner triplet of quadrupoles at L=10 m from the interaction point and the extension of the Achromatic Telescopic Squeezing (ATS) Scheme used for the High Luminosity-LHC project. The flexibility of this design has been studied in terms of minimising β^* and increasing L*. In this work, particle tracking is performed in a thin lens approximation of the LHeC proton lattice to compute the dynamic aperture and perform frequency map analysis for different types of chromatic correction schemes, in order to find the one who will provide the most beam stability and to study the effects of non linearities.
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MOPMA002	Optimising the Diamond DDBA Upgrade Lattice for Low Alpha Operation	lattice, optics, storage-ring, injection	525
	I.P.S. Martin, R. Bartolini DLS, Oxfordshire, United Kingdom R. Bartolini JAI, Oxford, United Kingdom
	The Diamond storage ring will be upgraded during 2016 by replacing one of the existing double bend achromat (DBA) cells with a double-DBA (DDBA) cell. One requirement of the upgrade is that following the installation of the new cell, Diamond should continue to offer dedicated user time in ‘low alpha’ mode. In this paper we describe the particular challenges relating to this task, and present the lattice design and optimisation studies undertaken so far. The paper concludes by discussing preliminary studies of adding a second DDBA cell into the storage ring. R.P. Walker et al., Proc. IPAC 2014, MOPRO103, (2014) ** I.P.S. Martin et al., Proc. IPAC 2013, MOPEA070, (2013)
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MOPMA028	Chromaticity and Dispersion in Nonlinear Integrable Optics	lattice, optics, focusing, 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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MOPMN024	Study of NSLS-II Dynamic Aperture Tolerances with Respect to Field and Orbit Errors	sextupole, lattice, quadrupole, alignment	751
	J. Choi, T.V. Shaftan, G.M. Wang BNL, Upton, Long Island, New York, USA
	Funding: DOE contract No: DE-AC02- 98CH10886 As the emittance of synchrotron light sources moves towards diffraction limit, magnet tolerances for reaching dynamic aperture for high injection efficiency and long lifetime become more stringent. Once nonlinear families are designed and the machine is built a machine operator may ask to which accuracy the linear optics and orbit should be corrected so to achieve reasonable dynamic aperture. We also studied the relations of the non-linear elements and beta-beat to the dynamic apertures by simulating NSLS-II storage ring lattice and the paper shows the results.
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MOPWI020	Development of Simple Tracking Libraries for ALS-U	lattice, Windows, simulation, framework	1192
	H. Nishimura, D. Robin, K. Song, C. Steier, C. Sun, W. Wan LBNL, Berkeley, California, USA
	Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 The conceptual lattice design study of a new diffraction-limited light source has become much more computer intensive than that for the 3rd-generation rings. We are in a process of upgrading our existing accelerator modeling and simulation libraries, Goemon* in C++ and a new version Tracy#, to fulfil such new demand. The C++ version has been actively used on the ALS HPC cluster for multi-objective optimization (MOGA) to optimize the ALS lattice, and recently for ALS-U*. This time, based on the current version in C#, we extracted its subset and ported it to C and C++. The routines are made thread-safe to enable OpenMP locally, and CPU-time profiling was extensively used to remove redundancies. The new refitting method of quad settings brought smooth switching from 5-dim to 6-dim. The data structure itself is simplified for the use on GPU that is based on our previous effort of tracking particles in GPU**. Tracy# itself is also upgraded to cooperate with these C/C++ versions. Their use from Python will be also mentioned. H. Nishimura, PAC01, 3066-3068. H. Nishimura, ICAP09. * C. Sun, et. al.,PAC11, 793-795. ** H. Tarawneh, et. al.,J.Phys.493 012020, 2014. *** H. Nishimura, et. al.,PAC11, 1764-1766.
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TUPWA013	Linear and Nonlinear Optimizations for the ESRF Upgrade Lattice	sextupole, lattice, injection, optics	1422
	N. Carmignani, L. Farvacque, S.M. Liuzzo, B. Nash, T.P. Perron, P. Raimondi, R. Versteegen, S.M. White ESRF, Grenoble, France
	The ESRF storage ring will be replaced in 2020 by a new hybrid multi bend achromat lattice with 134 pmrad equilibrium horizontal emittance. To determine the best working point, large scans of tunes and chromaticities have been performed, computing Touschek lifetime and dynamic aperture. From different working points, the multi-objective genetic algorithm NSGA-II has been used to optimize the nonlinear magnets values and some linear optics parameters. The analysis have been carried out on lattices with errors and corrections. The optimizations have produced lattices with longer lifetime and larger dynamic aperture for different working points with positive chromaticities.
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TUPWA014	Influence of errors on the ESRF Upgrade Lattice	survey, lattice, multipole, alignment	1426
	S.M. Liuzzo, J.C. Biasci, N. Carmignani, L. Farvacque, G. Gatta, G. Le Bec, D. Martin, B. Nash, T.P. Perron, P. Raimondi, R. Versteegen, S.M. White ESRF, Grenoble, France
	To determine the tolerable alignment and magnetic errors for the ESRF upgrade, we study their influence on Touschek lifetime and dynamic aperture. The correction of each set of errors studied is performed with a commissioning-like procedure, from the search for a closed orbit to the correction of resonance driving terms. Each kind of error is studied independently for each relevant family of magnets. The tolerable values deduced from the analysis are within the practical limits. The impact of the measured and simulated survey errors is also considered, defining the position of the currently installed lattice as the one of least impact for the realignment of X-ray beamlines.
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TUPWA052	Elettra 2.0 - The Next Machine	dipole, lattice, quadrupole, emittance	1532
	E. Karantzoulis Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	A next generation light source (ULS) to replace Elettra, the third generation Italian light source, is presented and discussed
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TUPWA060	Design of Diffraction Limited Light Source Ring with Multi-bend Lattice on a Torus-knot	lattice, emittance, quadrupole, alignment	1560
	A. Miyamoto, S. Sasaki HSRC, Higashi-Hiroshima, Japan
	We proposed a torus knot type synchrotron radiation ring in that the beam orbit does not close in one turn but closes after multiple turns around the ring. Currently, we are designing a new ring based on the shape of a (11, 3) torus knot for our future plan ‘HiSOR-II.’ This ring is mid-low energy light source ring with beam energy of 700 MeV. Recently some light source rings are achieving very low emittance that reaches a diffraction limited light by adopting a multi-bend scheme to the arc section of the ring. It is not difficult for low-mid energy VUV-SX light source ring because the electron beam less than 10 nmrad can provide the diffraction limited light in the energy less than 10eV. On the other hand, the multi-bend lattice demands many families of the magnets and spaces to place them, therefore it is difficult to achieve diffraction limited emittance for compact SR ring. However, for the torus-knot type accumulation ring, it is not difficult to realize such a low emittance. We present the details of the designing procedure and the specifications of the ultra-low emittance light source ring having innovatively odd shape.
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TUPJE013	Lattice Design of Low Beta Function at Interaction Point for TTX-II	lattice, electron, quadrupole, scattering	1641
	T. Rui, W.-H. Huang TUB, Beijing, People's Republic of China
	TTX-II is a storage ring being designed at Accelerator Laboratory in Tsinghua University as the second phase of Tsinghua Thomson scattering x-ray source (TTX), to increase the average photon flux generated. To achieve a small beta function at the interaction point, four pairs of quadrupole magnets, whose focusing strengths are optimized, are added to the baseline. The lattice design is presented in this work.
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TUPTY011	A Preliminary Design of the CEPC Interaction Region	interaction-region, detector, quadrupole, luminosity	2019
	Y. Wang, S. Bai, T.J. Bian, X. Cui, J. Gao, H. Geng, D. Wang, Y.S. Zhu IHEP, Beijing, People's Republic of China
	CEPC (Circular Electron and Positron Collider) is a circular Higgs Factory with optimized energy 240 GeV. In order to achieve luminosity as high as 2×10³⁴/cm²/s, CEPC calls for a small vertical beta function at IP (betay∗=1.2 mm) which was provided by the final focus of the interaction region. In this paper, a preliminary design of the CEPC interaction region was presented. The optimization of dynamic aperture with interaction region insertion and the machine detector interface was discussed as well.
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TUPTY035	Beam Dynamics Requirements for the Powering Scheme of the HL-LHC Triplet	quadrupole, controls, simulation, optics	2082
	M. Fitterer, R. De Maria, S.D. Fartoukh, M. Giovannozzi CERN, Geneva, Switzerland
	Funding: The HiLumi LHC Design Study is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404. For the HL-LHC, β^* values as small as 15 cm are envisaged as baseline scenario for the high luminosity insertions IR1 and IR5, thus leading to an increase of the maximum beta-functions in the inner triplet (IT). The larger beta-functions in the IT result in a higher sensitivity of the beam to any linear or non-linear, static or dynamic, field imperfections in the IT region. In this paper, we summarize accordingly the tolerances of the triplet power supplies in terms of current ripple, stability and reproducibility. Both the baseline IT powering scheme and other alternative schemes will be presented, the later reducing the tune shift caused by a current modulation and thus weakening its possible impact on the long term stability.
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TUPTY081	Design of a 6 TeV Muon Collider	sextupole, quadrupole, collider, octupole	2226
	M.-H. Wang, Y. Cai, Y. Nosochkov SLAC, Menlo Park, California, USA M.A. Palmer Fermilab, Batavia, Illinois, USA
	Funding: Work supported by the US Department of Energy contract DE-AC02-76SF00515 A design of a muon collider ring with the center of mass energy of 6 TeV is presented. The ring circumference is about 6.3 km, and the beta functions at collision point are 1 cm in both planes. The ring linear optics, the non-linear chromaticity correction scheme in the Interaction Region (IR), and the additional non-linear field orthogonal knobs are described in detail. The IR magnet specifications are based on the maximum pole tip field of 20 T in dipoles and 15 T in quadrupoles. The results of the beam dynamics optimization for maximum dynamic aperture are presented.
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TUPWI032	Progress on Optimization of the Nonlinear Beam Dynamics in the MEIC Collider Rings	sextupole, ion, optics, distributed	2311
	Y. Nosochkov, Y. Cai, M.K. Sullivan, M.-H. Wang, U. Wienands SLAC, Menlo Park, California, USA Y.S. Derbenev, F. Lin, V.S. Morozov, F.C. Pilat, Y. Zhang JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under US DOE Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357. Work supported by the US DOE Contract DE-AC02-76SF00515. One of the key design features of the Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is a small beta function at the interaction point (IP) allowing one to achieve a high luminosity of up to 10³⁴ cm^-2s^-1. The required strong beam focusing unavoidably causes large chromatic effects such as chromatic tune spread and beam smear at the IP, which need to be compensated. This paper reports recent progress in our development of a chromaticity correction scheme for the ion ring including optimization of dynamic aperture and momentum acceptance.
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Paper

Title

Other Keywords

Page

MOPWA019

Status of the Robinson Wiggler Project at the Metrology Light Source

wiggler, dipole, radiation, damping

132

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

The beam lifetime in electron storage rings concerns machines running in decay mode as well as machines doing top-up. A standard procedure to increase the lifetime is via bunch lengthening as the lifetime depends on the electron density in the bunch. Bunch lengthening is typically achieved with higher harmonic (Landau) cavities. As noted in *, there are several advantages in using a different approach: it is possible to increase the bunch length by installing a Transverse Gradient (Robinson) Wiggler, which allows to transfer damping between the horizontal and the longitudinal plane. While increasing the bunch length, the horizontal emittance is being reduced yielding advantages regarding the source size depending on the magnet optics. At the Metrology Light Source, a primary source standard used by Germanys national metrology institute (Physikalisch-Technische Bundesanstalt)**, such a scheme is being investigated. The current state of the project including dynamic aperture effects and synchrotron radiation issues of the device is being presented in the following.
* T. Goetsch et al.,WEPRO028 in Proceedings of IPAC2014, Dresden (Germany), 2014
** R. Klein et al., Phys. Rev. ST-AB 11, 110701, 2008

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MOPJE009

Lattice Design of the SSRF-U Storage Ring

emittance, storage-ring, lattice, injection

304

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

Multi-Bend Achromatic (MBA) cell has been well known to significantly reduce the beam emittance of the synchrotron radiation light sources in the past two decades. With the great development of the high gradient magnets, the small-aperture vacuum chamber and the precise alignment, the ultimate-emittance ring based on MBA lattice became practical in recent years. We present a preliminary lattice design for the upgraded SSRF storage ring based on a 7BA lattice in this paper. The circumference and the number of the straight sections are preserved for the existing tunnel. The beam energy is reduced to 3 GeV, and the beam emittance is reduced to about 200 pm.rad. The optimized dynamic aperture is about 10 mm in the horizontal plane, and a sufficient beam injection based on the closed orbit bump can be implemented.

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MOPJE015

Compensations of the DEPU Effects at the SSRF Storage Ring

quadrupole, coupling, injection, sextupole

307

M.Z. Zhang, B.C. Jiang, J.H. Tan, S.Q. Tian, M. Zhang, Q.L. Zhang
SINAP, Shanghai, People's Republic of China

A paired APPLE-II type Ellipsoid Polarized Undulator（DEPU）has been installed in the SSRF storage ring which can be mechanically switched between two undulators with difference period length. One of them get notable effects on the optics including CODs, tune, coupling and dynamic aperture. We report in this paper, feed forward tables of correctors, quadrupoles and skew quarupoles are used for the optics correction and sextupole optimization is used for the dynamic aperture recovery.

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MOPJE079

Tracking Studies in the LHeC Lattice

lattice, resonance, proton, electron

502

E. Cruz Alaniz, D. Newton
The University of Liverpool, Liverpool, United Kingdom
E. Cruz Alaniz, D. Newton
Cockcroft Institute, Warrington, Cheshire, United Kingdom
R. Tomás
CERN, Geneva, Switzerland

Funding: This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289485
The Large Hadron Electron Collider (LHeC) is a proposed upgrade of the LHC to provide electron-proton collisions and explore a new regime of energy and luminosity for nucleon-lepton scattering. A nominal design has previously been presented, featuring a lattice and optical configuration to focus one of the proton beams of the LHC (reaching a value of β^*=10 cm) and to collide it head-on with an electron beam to produce collisions with the desired luminosity of L=10³³ cm^-2 s^-1. The proton beam optics is achieved with the aid of a new inner triplet of quadrupoles at L*=10 m from the interaction point and the extension of the Achromatic Telescopic Squeezing (ATS) Scheme used for the High Luminosity-LHC project. The flexibility of this design has been studied in terms of minimising β^* and increasing L*. In this work, particle tracking is performed in a thin lens approximation of the LHeC proton lattice to compute the dynamic aperture and perform frequency map analysis for different types of chromatic correction schemes, in order to find the one who will provide the most beam stability and to study the effects of non linearities.

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MOPMA002

Optimising the Diamond DDBA Upgrade Lattice for Low Alpha Operation

lattice, optics, storage-ring, injection

525

I.P.S. Martin, R. Bartolini
DLS, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

The Diamond storage ring will be upgraded during 2016 by replacing one of the existing double bend achromat (DBA) cells with a double-DBA (DDBA) cell*. One requirement of the upgrade is that following the installation of the new cell, Diamond should continue to offer dedicated user time in ‘low alpha’ mode**. In this paper we describe the particular challenges relating to this task, and present the lattice design and optimisation studies undertaken so far. The paper concludes by discussing preliminary studies of adding a second DDBA cell into the storage ring.
* R.P. Walker et al., Proc. IPAC 2014, MOPRO103, (2014)
** I.P.S. Martin et al., Proc. IPAC 2013, MOPEA070, (2013)

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MOPMA028

Chromaticity and Dispersion in Nonlinear Integrable Optics

lattice, optics, focusing, 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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MOPMN024

Study of NSLS-II Dynamic Aperture Tolerances with Respect to Field and Orbit Errors

sextupole, lattice, quadrupole, alignment

751

J. Choi, T.V. Shaftan, G.M. Wang
BNL, Upton, Long Island, New York, USA

Funding: DOE contract No: DE-AC02- 98CH10886
As the emittance of synchrotron light sources moves towards diffraction limit, magnet tolerances for reaching dynamic aperture for high injection efficiency and long lifetime become more stringent. Once nonlinear families are designed and the machine is built a machine operator may ask to which accuracy the linear optics and orbit should be corrected so to achieve reasonable dynamic aperture. We also studied the relations of the non-linear elements and beta-beat to the dynamic apertures by simulating NSLS-II storage ring lattice and the paper shows the results.

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MOPWI020

Development of Simple Tracking Libraries for ALS-U

lattice, Windows, simulation, framework

1192

H. Nishimura, D. Robin, K. Song, C. Steier, C. Sun, W. Wan
LBNL, Berkeley, California, USA

Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231
The conceptual lattice design study of a new diffraction-limited light source has become much more computer intensive than that for the 3rd-generation rings. We are in a process of upgrading our existing accelerator modeling and simulation libraries, Goemon* in C++ and a new version Tracy#**, to fulfil such new demand. The C++ version has been actively used on the ALS HPC cluster for multi-objective optimization (MOGA) to optimize the ALS lattice***, and recently for ALS-U****. This time, based on the current version in C#, we extracted its subset and ported it to C and C++. The routines are made thread-safe to enable OpenMP locally, and CPU-time profiling was extensively used to remove redundancies. The new refitting method of quad settings brought smooth switching from 5-dim to 6-dim. The data structure itself is simplified for the use on GPU that is based on our previous effort of tracking particles in GPU*****. Tracy# itself is also upgraded to cooperate with these C/C++ versions. Their use from Python will be also mentioned.
* H. Nishimura, PAC01, 3066-3068.
** H. Nishimura, ICAP09.
*** C. Sun, et. al.,PAC11, 793-795.
**** H. Tarawneh, et. al.,J.Phys.493 012020, 2014.
***** H. Nishimura, et. al.,PAC11, 1764-1766.

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TUPWA013

Linear and Nonlinear Optimizations for the ESRF Upgrade Lattice

sextupole, lattice, injection, optics

1422

N. Carmignani, L. Farvacque, S.M. Liuzzo, B. Nash, T.P. Perron, P. Raimondi, R. Versteegen, S.M. White
ESRF, Grenoble, France

The ESRF storage ring will be replaced in 2020 by a new hybrid multi bend achromat lattice with 134 pmrad equilibrium horizontal emittance. To determine the best working point, large scans of tunes and chromaticities have been performed, computing Touschek lifetime and dynamic aperture. From different working points, the multi-objective genetic algorithm NSGA-II has been used to optimize the nonlinear magnets values and some linear optics parameters. The analysis have been carried out on lattices with errors and corrections. The optimizations have produced lattices with longer lifetime and larger dynamic aperture for different working points with positive chromaticities.

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TUPWA014

Influence of errors on the ESRF Upgrade Lattice

survey, lattice, multipole, alignment

1426

S.M. Liuzzo, J.C. Biasci, N. Carmignani, L. Farvacque, G. Gatta, G. Le Bec, D. Martin, B. Nash, T.P. Perron, P. Raimondi, R. Versteegen, S.M. White
ESRF, Grenoble, France

To determine the tolerable alignment and magnetic errors for the ESRF upgrade, we study their influence on Touschek lifetime and dynamic aperture. The correction of each set of errors studied is performed with a commissioning-like procedure, from the search for a closed orbit to the correction of resonance driving terms. Each kind of error is studied independently for each relevant family of magnets. The tolerable values deduced from the analysis are within the practical limits. The impact of the measured and simulated survey errors is also considered, defining the position of the currently installed lattice as the one of least impact for the realignment of X-ray beamlines.

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TUPWA052

Elettra 2.0 - The Next Machine

dipole, lattice, quadrupole, emittance

1532

E. Karantzoulis
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

A next generation light source (ULS) to replace Elettra, the third generation Italian light source, is presented and discussed

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TUPWA060

Design of Diffraction Limited Light Source Ring with Multi-bend Lattice on a Torus-knot

lattice, emittance, quadrupole, alignment

1560

A. Miyamoto, S. Sasaki
HSRC, Higashi-Hiroshima, Japan

We proposed a torus knot type synchrotron radiation ring in that the beam orbit does not close in one turn but closes after multiple turns around the ring. Currently, we are designing a new ring based on the shape of a (11, 3) torus knot for our future plan ‘HiSOR-II.’ This ring is mid-low energy light source ring with beam energy of 700 MeV. Recently some light source rings are achieving very low emittance that reaches a diffraction limited light by adopting a multi-bend scheme to the arc section of the ring. It is not difficult for low-mid energy VUV-SX light source ring because the electron beam less than 10 nmrad can provide the diffraction limited light in the energy less than 10eV. On the other hand, the multi-bend lattice demands many families of the magnets and spaces to place them, therefore it is difficult to achieve diffraction limited emittance for compact SR ring. However, for the torus-knot type accumulation ring, it is not difficult to realize such a low emittance. We present the details of the designing procedure and the specifications of the ultra-low emittance light source ring having innovatively odd shape.

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TUPJE013

Lattice Design of Low Beta Function at Interaction Point for TTX-II

lattice, electron, quadrupole, scattering

1641

T. Rui, W.-H. Huang
TUB, Beijing, People's Republic of China

TTX-II is a storage ring being designed at Accelerator Laboratory in Tsinghua University as the second phase of Tsinghua Thomson scattering x-ray source (TTX), to increase the average photon flux generated. To achieve a small beta function at the interaction point, four pairs of quadrupole magnets, whose focusing strengths are optimized, are added to the baseline. The lattice design is presented in this work.

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TUPTY011

A Preliminary Design of the CEPC Interaction Region

interaction-region, detector, quadrupole, luminosity

2019

Y. Wang, S. Bai, T.J. Bian, X. Cui, J. Gao, H. Geng, D. Wang, Y.S. Zhu
IHEP, Beijing, People's Republic of China

CEPC (Circular Electron and Positron Collider) is a circular Higgs Factory with optimized energy 240 GeV. In order to achieve luminosity as high as 2×10³⁴/cm²/s, CEPC calls for a small vertical beta function at IP (betay∗=1.2 mm) which was provided by the final focus of the interaction region. In this paper, a preliminary design of the CEPC interaction region was presented. The optimization of dynamic aperture with interaction region insertion and the machine detector interface was discussed as well.

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TUPTY035

Beam Dynamics Requirements for the Powering Scheme of the HL-LHC Triplet

quadrupole, controls, simulation, optics

2082

M. Fitterer, R. De Maria, S.D. Fartoukh, M. Giovannozzi
CERN, Geneva, Switzerland

Funding: The HiLumi LHC Design Study is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.
For the HL-LHC, β^* values as small as 15 cm are envisaged as baseline scenario for the high luminosity insertions IR1 and IR5, thus leading to an increase of the maximum beta-functions in the inner triplet (IT). The larger beta-functions in the IT result in a higher sensitivity of the beam to any linear or non-linear, static or dynamic, field imperfections in the IT region. In this paper, we summarize accordingly the tolerances of the triplet power supplies in terms of current ripple, stability and reproducibility. Both the baseline IT powering scheme and other alternative schemes will be presented, the later reducing the tune shift caused by a current modulation and thus weakening its possible impact on the long term stability.

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TUPTY081

Design of a 6 TeV Muon Collider

sextupole, quadrupole, collider, octupole

2226

M.-H. Wang, Y. Cai, Y. Nosochkov
SLAC, Menlo Park, California, USA
M.A. Palmer
Fermilab, Batavia, Illinois, USA

Funding: Work supported by the US Department of Energy contract DE-AC02-76SF00515
A design of a muon collider ring with the center of mass energy of 6 TeV is presented. The ring circumference is about 6.3 km, and the beta functions at collision point are 1 cm in both planes. The ring linear optics, the non-linear chromaticity correction scheme in the Interaction Region (IR), and the additional non-linear field orthogonal knobs are described in detail. The IR magnet specifications are based on the maximum pole tip field of 20 T in dipoles and 15 T in quadrupoles. The results of the beam dynamics optimization for maximum dynamic aperture are presented.

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TUPWI032

Progress on Optimization of the Nonlinear Beam Dynamics in the MEIC Collider Rings

sextupole, ion, optics, distributed

2311

Y. Nosochkov, Y. Cai, M.K. Sullivan, M.-H. Wang, U. Wienands
SLAC, Menlo Park, California, USA
Y.S. Derbenev, F. Lin, V.S. Morozov, F.C. Pilat, Y. Zhang
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under US DOE Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357. Work supported by the US DOE Contract DE-AC02-76SF00515.
One of the key design features of the Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is a small beta function at the interaction point (IP) allowing one to achieve a high luminosity of up to 10³⁴ cm^-2s^-1. The required strong beam focusing unavoidably causes large chromatic effects such as chromatic tune spread and beam smear at the IP, which need to be compensated. This paper reports recent progress in our development of a chromaticity correction scheme for the ion ring including optimization of dynamic aperture and momentum acceptance.

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