Keyword: dynamic-aperture
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MOPAB155 Characterization of the Longitudinal Acceptance in a Storage Ring with RF Pinger cavity, synchrotron, storage-ring, damping 497
 
  • G.M. Wang, B. Holub, Y. Li, J. Rose, T.V. Shaftan
    BNL, Upton, Long Island, New York, USA
  
  In modern generation light sources, it is desired to have SR performance at high beam current, low horizontal emittance with small coupling, resulting in intense Touschek scattering, which is the dominant limitation of beam lifetime. Touschek scattering strongly depends on momentum aperture. Understanding momentum aperture is extremely important. NSLS II storage ring RF system has the digital ramp control function, enabling rapid change of the cavity phase and amplitude. This makes the possibility to ping the beam in longitudinal phase space and directly measure the longitudinal acceptance, in contrast with traditional indirect way to understand it from other aspect of parameters. In this paper, we present the tool, longitudinal pinger, its application to characterize NSLS II longitudinal acceptance and localize the momentum aperture limit with SR BPMs.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB155  
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MOPIK079 The Off-Axis Injection Lattice Design of HEPS Storage Ring injection, lattice, storage-ring, multipole 716
 
  • Y.M. Peng, D. Ji, Y. Jiao, S.K. Tian, J.Q. Wang, G. Xu
    IHEP, Beijing, People's Republic of China
  
  The dynamic aperture size determines the injection scheme to a large extent. The aim of storage ring design of HEPS is to achieve ultralow emittances on both transverse planes. This will bring very strong lattice nonlinearities. The present nominal design is a hybrid 7BA design with effective dynamic aperture of about 3 mm both in horizontal and vertical plane. Due to the restriction of dynamic aperture of this lattice, on-axis injection is the only choice . But, on-axis injection will bring a very big challenge for injector or injection kicker, if it is feasible to obtain a large dynamic aperture, off-axis injection is a favoured choice. In this paper, we will show the preliminary study of the lattice design with a sufficient dynamic aperture for pulsed multipole injection..  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK079  
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TUPVA003 Advance on Dynamic Aperture at Injection for FCC-hh dipole, optics, injection, target 2027
 
  • B. Dalena, D. Boutin, A. Chancé
    CEA/IRFU, Gif-sur-Yvette, France
  • B.J. Holzer, D. Schulte
    CERN, Geneva, Switzerland
  
  Funding: This Research and Innovation Action project submitted to call H2020-INFRADEV-1-2014-1 receives funding from the European Union's H2020 Framework Programme under grant agreement no. 654305.
In the hadron machine option, proposed in the context of the Future Circular Colliders (FCC) study, the first evaluation of dipole field quality, based on the Nb3Sn technology, has shown a Dynamic Aperture at injection above the LHC target value. In this paper the effect of field imperfections on the dynamic aperture, using the updated lattice design, is presented. Tolerances on the main multipole components are evaluated including feed-down effect. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA003  
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TUPVA026 Beam-Beam Studies for FCC-hh optics, simulation, luminosity, resonance 2109
 
  • J. Barranco García, T. Pieloni, C. Tambasco
    EPFL, Lausanne, Switzerland
  • X. Buffat, S.V. Furuseth, C. Tambasco
    CERN, Geneva, Switzerland
  • S.V. Furuseth
    NTNU, Trondheim, Norway
  
  Funding: This works was performed in the framework of the European Circular 'Energy Fr'ontier Collider Study, H2020 Framework Programme under grant agreement no. 654305. We acknowledge support from the Swiss State Secretariat for Education, Research and Innovation SERI.
The Future Circular Collider hadron-hadron (FCC-hh) design study is currently exploring different IR design possibilities including round and flat optics or different crossing schemes. The present study intends to evaluate each scenario from the beam-beam effects point of view. In particular the single particle long term stability to maximize beam lifetimes and luminosity reach is used to quantify the differences. The impact of strong head on interactions on the beam quality and lifetime is addressed by means of GPU accelerated simulations code featuring a weak-strong 6-dimensional beam-beam interaction. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA026  
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TUPVA027 Study of Beam-Beam Long Range Compensation with Octupoles octupole, optics, resonance, beam-beam-effects 2113
 
  • T. Pieloni, J. Barranco García, C. Tambasco
    EPFL, Lausanne, Switzerland
  • X. Buffat, C. Tambasco
    CERN, Geneva, Switzerland
  
  Funding: The European Circular Energy-Frontier Collider Study (EuroCirCol), EU's Horizon 2020 grant No 654305.
Long range beam-beam effects are responsible for particle losses and define fundamental operational parameters of colliders (i.e. crossing angles, intensities, emittances, β*). In this study we propose octuple magnets as a possible scheme to efficiently compensate long-range beam-beam interactions with a global correction scheme. The impact and improvements on the dynamic aperture of colliding beams together with estimates of the luminosity potentials are discussed for the HL-LHC upgrade and extrapolations made for the FCC project. Results are compared to other compensating schemes. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA027  
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TUPVA038 Non Linear Field Correction Effects on the Dynamic Aperture of the FCC-hh quadrupole, lattice, collider, interaction-region 2143
 
  • E. Cruz Alaniz, A. Seryi
    JAI, Oxford, United Kingdom
  • E.H. Maclean, R. Martin, R. Tomás
    CERN, Geneva, Switzerland
  
  Funding: European Union's Horizon 2020 research and innovation programme under grant No 654305.
The Future Circular Collider (FCC) design study aims to develop the designs of possible circular colliders in the post LHC era. In particular the FCC-hh will aim to produce proton-proton collisions at a center of mass energy of 100 TeV. Given the large beta functions and integrated length of the quadrupoles of the final focus triplet the effect of systematic and random non linear errors in the magnets are expected to have a severe impact on the stability of the beam. Following the experience on the HL-LHC this work explores the implementation of non-linear correctors to minimize the resonance driving terms arising from the errors of the triplet. Dynamic aperture studies are then performed to study the impact of this correction. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA038  
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WEOAB2 Correction of Beta-Beating Due to Beam-Beam for the LHC and Its Impact on Dynamic Aperture sextupole, optics, quadrupole, luminosity 2512
 
  • L.E. Medina Medrano, J. Barranco García, X. Buffat, Y. Papaphilippou, T. Pieloni, R. Tomás
    CERN, Geneva, Switzerland
  • J. Barranco García, T. Pieloni
    EPFL, Lausanne, Switzerland
  • L.E. Medina Medrano
    UGTO, Leon, Mexico
  
  Funding: This work is supported by the European Circular Energy-Frontier Collider Study, H2020 programme under grant agreement no. 654305, by the Swiss State Secretariat for Education, Research and Innovation SERI, and by the Beam project (CONACYT, Mexico).
Minimization of the beta-beating at the two main interaction points of the LHC arising from the head-on and long-range beam-beam interactions can be performed by adjusting the strength of quadrupole or sextupole correctors. This compensation scheme is applied to the current LHC optics where the results show a significant reduction of the peak and RMS beta-beating; and the impact on the dynamic aperture is computed. A proposal for a similar strategy to be adopted in the High Luminosity LHC is also discussed. 		 
slides icon Slides WEOAB2 [6.292 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEOAB2  
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WEPAB043 DQBA Lattice Option for the KEK-LS Project emittance, lattice, insertion-device, insertion 2675
 
  • K. Harada, N. Higashi, S. Nagahashi, N. Nakamura, S. Sakanaka, A. Ueda
    KEK, Ibaraki, Japan
  • S.M. Liuzzo
    ESRF, Grenoble, France
  
  KEK-LS is a fourth generation 3GeV light source and will be constructed in KEK Tsukuba campus. The lattice is 20 cells of ESRF type HMBA (Hybrid Multi Bend Achromat) with short straight section that enables to double the numbers of insertion device beam lines. The circumference is about 570m, and the horizontal natural emittance about 133pmrad. The conceptual design report (CDR) was published in October 2016. Adding two quadrupole magnets to the short straight section of the original lattice in CDR, the lattice design flexibility, emittance and dynamic apertures are improved. In this presentation, we show this new DQBA (Double Quadrupole Bend Achromat) lattice option for KEK-LS project.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB043  
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WEPAB046 New HMBA Lattice for PF-AR lattice, injection, emittance, optics 2684
 
  • N. Higashi, K. Harada, Y. Kobayashi, S. Nagahashi, N. Nakamura, A. Ueda
    KEK, Ibaraki, Japan
  
  Photon Factory Advanced Ring (PF-AR) has been operated for users about 30 years from 1987. The lattice and optics are not almost changed from the original one as the TRISTAN booster ring constructed in 1984. The lattice employs FODO structure and the horizontal emittance for the 6.5 GeV user run is about 300 nmrad. In order to improve the performance of PF-AR dramatically, the full replacement of the accelerator to the ESRF type HMBA (Hybrid multi bend achromat) lattice is examined. In order to geometrically fit the new lattice to the present PF-AR tunnel, the new ring consists of 12 cells with four long straight sections. The emittance is improved to about 500 pmrad at 3 GeV. With the present user experimental hall at the north half of the ring, at least eight undulator beam lines can be constructed. The simulated dynamic aperture is about 1.5 cm at the long straight section with reasonable magnetic errors and COD correction. The Touschek lifetime is about 6 hours. The beam injection with conventional injection system causes no problem and the beam lifetime is long enough.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB046  
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WEPAB069 Possible Suppression of Head-Tail Instability by a Feedback Kicker for a Light Source Without Any Sextupole sextupole, storage-ring, emittance, resonance 2738
 
  • T.-Y. Lee, B.H. Oh
    PAL, Pohang, Kyungbuk, Republic of Korea
  
  As storage ring based light sources pursue as low emittance as possible down to the diffraction limited number by adopting as many bending magnets and quadrupoles in a cell, the number of sextupole magnets required to correct chromaticity and secure a sufficiently big dynamic aperture grows substantially. As a result, the circumference of a multi-bend achromatic lattice storage ring is typically very long. This paper discusses over a possible scheme to run a storage ring without sextupole magnets at all and suppress the head-tail instability by using a transverse feedback kicker.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB069  
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WEPAB086 Design and Optimisation of SPS-II Storage Ring emittance, lattice, dipole, undulator 2773
 
  • P. Klysubun, T. Pulampong, P. Sudmuang
    SLRI, Nakhon Ratchasima, Thailand
  
  Siam Photon Source (SPS) in Thailand has been operating and providing synchrotron radiation to users for more than a decade, leading to growing user community in South East Asia region. This gives rise to the possibility of constructing a new 3 GeV light source which could provide synchrotron light with higher photon energy and higher brilliance than the existing 1.2 GeV machine. Hybrid multi-bend achromat (HMBA) lattice design providing small natural beam emittance is a promising choice. In this paper, the Double-Triple Bend Achromat (DTBA) design with extra straight section scaled from Diamond Light Source upgrade lattice [ref.] is presented. Lattice optimisation with simplified magnet specifications still allows natural emittance of about 900 pm'rad for a 321.3 m circumference ring with sufficient dynamic aperture.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB086  
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WEPIK017 100 km CEPC Parameters and Lattice Design luminosity, sextupole, collider, optics 2958
 
  • D. Wang, T.J. Bian, X. Cui, J. Gao, H. Geng, Q. Qin, B. Sha, N. Wang, Y. Wang, C.H. Yu, J.Y. Zhai, C. Zhang, Y. Zhang
    IHEP, Beijing, People's Republic of China
  • F. Su
    Institute of High Energy Physics (IHEP), People's Republic of China
  
  The 100km double ring configuration with shared su-perconducting RF system has been defined as baseline by the circular electron positron collider (CEPC) steering committee. Based on this new scheme, we will get higher luminosity for Higgs (+170%) keeping the beam power in preliminary conceptual design report (Pre-CDR) or to reduce the beam power (19 MW) while keeping same luminosity. CEPC will be compatible with W and Z ex-periment. The luminosity for Z is designed at the level of 1035 cm-2s−1. The requirement for the energy acceptance of Higgs has been reduced to 1.5% by enlarging the ring to 100 km. The optics of arc and final focus system (FFS) with crab sextupoles has been designed, and also some primary dynamic aperture (DA) results were introduced.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK017  
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WEPIK022 CEPC Booster Lattice Design lattice, resonance, collider, booster 2968
 
  • T.J. Bian, X. Cui, J. Gao, C. Zhang
    IHEP, Beijing, People's Republic of China
  
  In September 2012, Chinese scientists proposed a Circular Electron Positron Collider(CEPC) at 240 GeV centre of mass for Higgs studies. The CEPC booster(CEPCB) provides 120 GeV electron and positron beams to the CEPC collider for top-up injection. We foucus on the beam dynamic study for CEPCB and analyse the key point of CEPCB lattice design. In this paper, a lattice design with good dynamic aperture is proposed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK022  
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WEPIK044 Effects of Crab Cavitiy Multipoles on JLEIC Ion Ring Dynamic Aperture multipole, cavity, ion, dipole 3025
 
  • S.I. Sosa Guitron, S.U. De Silva, J.R. Delayen
    ODU, Norfolk, Virginia, USA
  • V.S. Morozov
    JLab, Newport News, Virginia, USA
  
  We study the effects of crab cavity multipole fields on the beam dynamic aperture of the Jefferson Lab Electron-Ion Collider (JLEIC) ion ring. Crab cavities are needed to compensate for luminosity loss due to a 50 mrad crossing angle at the interaction point. New compact crab cavity designs are interesting as they do not require considerable space in the ring but their non-linear field needs to be well understood. In this contribution, we study the impact of field multipoles on the beam dynamic aperture and report tolerance values for crab cavity multipoles.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK044  
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WEPIK052 Energy Acceptance and on Momentum Aperture Optimization for the Sirius Project lattice, storage-ring, betatron, resonance 3041
 
  • P.S. Dester, L. Liu, F.H. de Sá
    LNLS, Campinas, Brazil
  
  A fast objective function to calculate Touschek lifetime and on momentum aperture is essential to explore the vast search space of strength of quadrupole and sextupole families in Sirius. Touschek lifetime is estimated by using the energy aperture (dynamic and physical), rf system parameters and driving terms. Non-linear induced betatron oscillations are considered to determine the energy aperture. On momentum aperture is estimated by using a chaos indicator and resonance crossing considerations. Touschek lifetime and on momentum aperture constitute the objective function, which was used in a multi-objective genetic algorithm to perform an optimization for Sirius.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK052  
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WEPIK053 Studies of Delta-Type Undulators for Sirius undulator, polarization, storage-ring, lattice 3045
 
  • L.N.P. Vilela, L. Liu, X.R. Resende, F.H. de Sá
    LNLS, Campinas, Brazil
  
  In this work we present the studies of the effects of Delta-type undulators in the storage ring beam dynamics of Sirius. The undulators were included in the ring model as kick maps and their effects on tune shift, dynamic aperture and beam lifetime were evaluated.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK053  
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WEPIK067 Beam-Dynamics Simulation Studies for the HESR simulation, dipole, multipole, coupling 3084
 
  • J.H. Hetzel, U. Bechstedt, J. Böker, A. Lehrach, B. Lorentz, S. Quilitzsch, H. Soltner, R. Tölle
    FZJ, Jülich, Germany
  • A. Lehrach
    RWTH, Aachen, Germany
  
  The High Energy Storage Ring (HESR) is part of the future Facility for Antiproton and Ion Research (FAIR) placed in Darmstadt (Germany). The HESR is designed for antiprotons with a momentum range from 1.5 GeV/c to 15 GeV/c, but will as well be suitable to provide heavy ion beams with a momentum range from approximately 0.6 GeV/c to 5.8 GeV/c. To guarantee smooth operation it is crucial to verify and to optimize the design with beam-dynamics simulations. Within recent studies* calculations based on a variant of the Lyapunov exponent were carried out to estimate the dynamic aperture. The studies could reproduce expected influences as reduced aperture due to tune resonances and tune shifts due to coupling. Thus they can be extended to investigate the dynamic behaviour of the beam and identify the main restrictions to the dynamic aperture near the chosen betatron tune. Furthermore ongoing measurements of the magnetic fields of the already produced bending dipoles and quadrupoles deliver a more precise insight to the harmonic content of these elements. Thus the existing simulations could now be updated by including the new measurement results.
*J. Hetzel, A. Lehrach, U. Bechstedt, J. Böker, B. Lorentz, R. Tölle: Towards Beam-Dynamics Simulations Including More Realistic Field Descriptions for the HESR, IPAC'16 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK067  
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WEPIK080 Preliminary Study of Beam Dynamics Compensation for the Elliptically Polarized Undulator at the HLS-II electron, simulation, software, undulator 3114
 
  • Z.H. Yang, Z.H. Bai, W. Li, L. Wang
    USTC/NSRL, Hefei, Anhui, People's Republic of China
  
  An elliptically polarized undulator (EPU) was installed at the upgraded Hefei Light Source, HLS-II, for special users. Due to that the area of good field of the EPU is not large enough, the resulting beam dynamics is serious. At present, the lattice is changed to lower beta functions at the EPU to solve this problem. However, the compensation for the EPU is necessary for better operation of the machine in the future. In this paper, we used the surface fitting method to extract the Hamiltonian of the EPU from the real surface magnetic field data. Thus, we can obtain the effective Hamiltonian of the ring, which can be analyzed using normal form or other techniques. Then the beam dynamics effects resulting from the EPU can be compensated by optimizing the nonlinear quantities with striplines.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK080  
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WEPIK092 Effect of Linear Coupling on Nonlinear Observables at the LHC coupling, injection, simulation, octupole 3151
 
  • E.H. Maclean, F.S. Carlier, M. Giovannozzi, T. Persson, R. Tomás
    CERN, Geneva, Switzerland
  
  Simulation work during LHC Run 1 established that linear coupling had a large impact on nonlinear observables such amplitude detuning and dynamic aperture. It is generally taken to be the largest single source of uncertainty in the modelling of the LHC's nonlinear single particle dynamics. Measurements in 2016 sought to confirm this impact of linear coupling with beam. This paper summarizes the observed influence of linear coupling on various nonlinear observables in the LHC.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK092  
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WEPIK093 New Methods for Measurement of Nonlinear Errors in LHC Experimental IRs and Their Application in the HL-LHC dipole, resonance, optics, collider 3155
 
  • E.H. Maclean, F.S. Carlier, J.M. Coello de Portugal, A. Garcia-Tabares, M. Giovannozzi, L. Malina, T. Persson, P.K. Skowroński, R. Tomás
    CERN, Geneva, Switzerland
  
  Studies of nonlinear errors in LHC experimental insertions (IRs) during Run 1 were based upon feed-down to tune and coupling from the crossing angle orbit bumps. Useful for validating the magnetic model, this method alone is of limited use to understand discrepancies between magnetic and beam-based measurement. Feed-down from high-order multipoles is also difficult to observe. During Run 2 several alternative methods were tested in the LHC. This paper summarizes the results of these tests, and comments on their potential application to the High-Luminosity LHC upgrade.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK093  
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WEPIK122 Applying Square Matrix to Optimize Storage Ring Nonlinear Lattice lattice, resonance, sextupole, storage-ring 3241
 
  • Y. Li, L. Yu
    BNL, Upton, Long Island, New York, USA
  
  Funding: Supported by US DOE Contract No. DE-AC02-98CH10886 and DE-SC0012704.
A new method of using linear algebra technique to analyze periodical nonlinear beam dynamics is presented. For a given dynamical system, a square upper triangular transfer matrix is constructed out of a one turn Taylor transfer map. First we separate the matrix into different low dimensional invariant subspaces according to their eigenvalues. Then a stable Jordan transformation can be obtained on each subspace. The transformation provides an excellent action-angle approximation to the solution of the nonlinear dynamics. And the deviation of the new action from constancy provides a measure of the nonlinearity of the motions, which provides a novel method to optimize the nonlinear dynamic system. We applied this method to optimize various rings, such as NSLS-II, SPEAR3, and APS-U lattice, the promising dynamic aperture have been achieved from both tracking simulation and experimental measurements. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK122  
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THXA1 Beam-Based Optimization of Storage Ring Nonlinear Beam Dynamics sextupole, injection, storage-ring, resonance 3627
 
  • X. Huang, J.A. Safranek
    SLAC, Menlo Park, California, USA
  
  Funding: Work supported in part by the U.S. Department of Energy under contract number DE-AC02-76SF00515.
This paper will present considerations and algorithms for direct online optimization of the nonlinear beam dynamics of existing and future storage rings. The experimental setup and results from using this approach to improve the dynamic aperture of the SPEAR3 storage ring, using the robust conjugate direction search method and the particle swarm optimization method, will be covered. 		 
slides icon Slides THXA1 [1.589 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THXA1  
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THPAB008 Particle Swarm Optimization Algorithm Applied in Online Commissioning at the MLS and BESSY II sextupole, injection, storage-ring, simulation 3700
 
  • J. Li, J. Feikes, P. Goslawski, M. Ries
    HZB, Berlin, Germany
  
  Particle Swarm Optimization (PSO) is a population based optimization technique inspired by the social behaviour of bird flocking. This algorithm has been successfully used for beam dynamics simulation due to its excellent capability to deal with large-dimensional optimization problems. At the MLS and BESSY II PSO was first successfully applied to improve the lifetime by 20~30% within only 10 iterations respectively. Now the PSO has been implemented as a multifunctional online optimizer to improve the machine performance. This paper presents some results of online experiments.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB008  
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THPAB056 Dynamic Aperture Studies of the Long-Range Beam-Beam Interaction at the LHC simulation, emittance, luminosity, coupling 3840
 
  • M.P. Crouch, R.B. Appleby
    UMAN, Manchester, United Kingdom
  • J. Barranco García, T. Pieloni, C. Tambasco
    EPFL, Lausanne, Switzerland
  • X. Buffat, M. Giovannozzi, E.H. Maclean
    CERN, Geneva, Switzerland
  • B.D. Muratori
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  
  Long-range beam-beam interactions dictate the choice of operational parameters for the LHC, such as the crossing angle and β* and therefore the luminosity reach for the collider. These effects can lead to particle losses, closed orbit effects and emittance growth. Defining how these effects depend on the beam-beam separation will determine the minimum crossing angle and the β* the LHC can operate. In this article, analysis from a dedicated machine study is presented in which the crossing angle was reduced in steps and the impact on beam intensity and luminosity lifetimes were observed. Based on the observations during the machine study, the intensity decays are compared to expectations from models. Estimates of the luminosity reach in the LHC are also computed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB056  
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THPAB084 Integration of the Full-Acceptance Detector Into the JLEIC detector, ion, collider, solenoid 3912
 
  • G.H. Wei, F. Lin, V.S. Morozov, F.C. Pilat, Y. Zhang
    JLab, Newport News, Virginia, USA
  • Y.M. Nosochkov
    SLAC, Menlo Park, California, USA
  • M.-H. Wang
    Self Employment, Private address, USA
  
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contracts No. DE-AC05-06OR23177 and DE-AC02-06CH11357. Work supported also by the U.S. DOE Contract DE-AC02-76SF00515.
For physics requirements, the JLEIC (Jefferson Lab Electron Ion Collider) has a full-acceptance detector, which brings many new challenges to the beam dynamics integration. For example, asymmetric lattice and beam envelopes at interaction region (IR), forward detection, and large crossing angle with crab dynamics. Also some common problems complicate the picture, like coupling and coherent orbit from detector solenoid, high chromaticity and high multipole sensitivity from low beta-star at interaction point (IP), collision mode with different energy and ion species. Meanwhile, to get a luminosity level of a few 1033 cm-2ses−1, small beta-star are necessary at the IP, which also means large beta in the final focus area, chromaticity correction sections, etc. This sets a constraint on the field quality of magnets in large beta areas, in order to ensure a large enough dynamic aperture (DA). In this context, limiting multipole components of magnets are surveyed to get a standard line. And continuously, multipole magnets as dedicated correctors are studied to provide semi-local corrections of specific multipole components beyond the standard line. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB084  
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