Keyword: storage-ring
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MOXA01 Commissioning and Restart of ESRF-EBS SRF, injection, lattice, MMI 1
 
  • S.M. White, N. Carmignani, L.R. Carver, J. Chavanne, L. Farvacque, L. Hardy, J. Jacob, G. Le Bec, S.M. Liuzzo, T.P. Perron, Q. Qin, P. Raimondi, J.-L. Revol, K.B. Scheidt
    ESRF, Grenoble, France
 
  The ESRF operates a 6 GeV 4th generation light source, the ESRF-EBS. This storage ring is the first to implement the Hybrid Multi-Bend Achromat lattice (HMBA). The HMBA lattice provides a reduction of the horizontal emittance of approximately a factor 30 with respect to the former Double Bend Achromat (DBA) structure, considerably improving the brilliance and transverse coherence of the ESRF accelerator complex while maintaining large horizontal acceptance and excellent lifetime performance. In this report, the characteristics of the HMBA lattice will be reviewed and the beam commissioning results and first operation experience of the new ESRF storage ring will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOXA01  
About • paper received ※ 11 May 2021       paper accepted ※ 31 August 2021       issue date ※ 01 September 2021  
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MOXA02 Status of the APS-U Project emittance, lattice, injection, photon 7
 
  • R.O. Hettel
    ANL, Lemont, Illinois, USA
 
  Funding: Work supported by the U.S. Department of Energy, Office of Sci- ence, Office of Basic Energy Sciences, under Contract No. DE-AC02- 06CH11357.
The Advanced Photon Source Upgrade (APS-U) project at the Argonne National Laboratory will re-place the existing 7-GeV, 1.1-km circumference dou-ble bend storage ring lattice with a new 6-GeV hybrid 7BA lattice that will reduce horizontal electron emit-tance from 3 nm-rad to 42 pm-rad, including IBS ef-fects for 200-mA operation. With new optimized per-manent magnet and superconducting undulators, an increase in spectral brightness of two to three orders of magnitude in the 10-100 keV X-ray energy range will be realized. The project includes nine new high performance beamlines and fifteen enhanced beam-lines that will exploit the high brightness and coher-ence of the new facility. The project is in full swing, more than 50% complete by cost, and is on schedule for first beam sometime in mid-2024, a slip of 10 months from the original schedule due to the impact of COVID-19. Project status, challenges and outstanding issues will be discussed in this article.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOXA02  
About • paper received ※ 21 May 2021       paper accepted ※ 09 June 2021       issue date ※ 11 August 2021  
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MOXA03 Sirius Commissioning Results and Operation Status MMI, alignment, injection, operation 13
 
  • L. Liu, M.B. Alves, A.C.S. Oliveira, X.R. Resende, F.H. de Sá
    LNLS, Campinas, Brazil
 
  Sirius is a 4th generation 3 GeV synchrotron light source that has just finalized the first commissioning phase at the Brazilian Center for Research in Energy and Materials (CNPEM) campus in Campinas, Brazil. This paper describes the main Accelerator Physics issues faced during the storage ring commissioning, methods that were used to work them out and the current operation status of the machine.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOXA03  
About • paper received ※ 20 May 2021       paper accepted ※ 10 June 2021       issue date ※ 16 August 2021  
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MOPAB035 Modified Lattice of the Compact Storage Ring in the cSTART Project at Karlsruhe Institute of Technology sextupole, quadrupole, lattice, octupole 159
 
  • A.I. Papash, E. Bründermann, B. Härer, A.-S. Müller, R. Ruprecht, J. Schäfer, M. Schuh
    KIT, Karlsruhe, Germany
 
  A very large acceptance compact storage ring (VLA-cSR) is under design at the Institute for Beam Physics and Technology (IBPT) of the Karlsruhe Institute of Technology (KIT, Germany). The combination of a compact storage ring and a laser wakefield accelerator (LWFA) might be the basis for future compact light sources and advancing user facilities. Meanwhile, the post-LWFA beam should be adapted for storage and accumulation in a dedicated storage ring. Modified geometry and lattice of a VLA-cSR operating at 50 MeV energy range have been studied in detailed simulations. The main features of a new model are described here. The new design, based on 45° bending magnets, is suitable to store the post-LWFA beam with a wide momentum spread (1% to 2%) as well as ultra-short electron bunches in the fs range from the Ferninfrarot Linac- Und Test- Experiment (FLUTE). The DBA-FDF lattice with relaxed settings, split elements, and higher-order optics of tolerable strength allows improving the dynamic aperture to an acceptable level. This contribution discusses the lattice features in detail and different possible operation schemes of a VLA-cSR.  
poster icon Poster MOPAB035 [1.405 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB035  
About • paper received ※ 10 May 2021       paper accepted ※ 27 May 2021       issue date ※ 24 August 2021  
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MOPAB036 Different Operation Regimes at the KIT Storage Ring KARA (Karlsruhe Research Accelerator) operation, optics, lattice, electron 163
 
  • A.I. Papash, M. Brosi, E. Huttel, A. Mochihashi, A.-S. Müller, R. Ruprecht, P. Schreiber, M. Schuh, N.J. Smale
    KIT, Karlsruhe, Germany
 
  The KIT storage ring KARA operates in a wide energy range from 0.5 to 2.5 GeV. Different operation modes have been implemented at KARA, so far, the double-bend achromat (DBA) lattice with non-dispersive straight sections, the theoretical minimum emittance (TME) lattice with distributed dispersion, different versions of low-compaction factor optics with highly stretched dispersion function. Short bunches of a few ps pulse width are available at KARA. Low-alpha optics has been simulated, tested and implemented in a wide operational range of the storage ring and is now routinely used at 1.3 GeV for studies of beam bursting effects caused by coherent synchrotron radiation in the THz frequency range. Different non-linear effects, in particular residual high-order components of the magnetic field, generated in high-field superconducting wigglers have been studied and cured. Based on good agreement between computer simulations and experiments, a new operation mode at high vertical tune was implemented. The beam performance during user operation as well as at low-alpha regimes has been improved. A specific optic with negative compaction factor was simulated, tested and is in operation.  
poster icon Poster MOPAB036 [1.477 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB036  
About • paper received ※ 13 May 2021       paper accepted ※ 08 June 2021       issue date ※ 29 August 2021  
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MOPAB037 On Possibility of Alpha-buckets Detecting at the KIT Storage Ring KARA (Karlsruhe Research Accelerator) operation, optics, synchrotron, electron 167
 
  • A.I. Papash, T. Boltz, M. Brosi, A.-S. Müller, R. Ruprecht, P. Schreiber, M. Schuh, N.J. Smale
    KIT, Karlsruhe, Germany
 
  Computer studies of longitudinal motion have been performed with the objective to estimate the possibility of detection of alpha-buckets at the KIT storage ring KARA (Karlsruhe Research Accelerator). The longitudinal equations of motion and the Hamiltonian were expanded to high order terms of the energy deviation of particles in a beam. Roots of third order equation for three leading terms of momentum compaction factor and free energy independent term were derived in a form suitable for analytical estimations. Averaged quadratic terms of closed orbit distortions caused by misalignment of magnetic elements in a ring lead to orbit lengthening independent of particle energy deviation. Particle transverse excursions were estimated and are taken into account. Simulations have been bench-marked on existing experiments at Metrology Light Source (MLS) in Berlin (Germany) and SOLEIL (France). Parameters of three simultaneous beams and alpha buckets at MLS and SOLEIL have been reproduced with high accuracy. A computer model of KARA was used to predict behavior and the dynamics of possible simultaneous beams in the ring.  
poster icon Poster MOPAB037 [1.269 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB037  
About • paper received ※ 11 May 2021       paper accepted ※ 28 May 2021       issue date ※ 29 August 2021  
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MOPAB052 Study of Beam Transmission Efficiency in Injection and Ramping Process of the HEPS Booster lattice, booster, injection, simulation 225
 
  • Y.M. Peng, Z. Duan, Y. Jiao, C. Meng
    IHEP, Beijing, People’s Republic of China
 
  A high-bunch-charge mode, with a bunch charge of approximately 14.4 nC at 200 mA, has been proposed for the storage ring of High Energy Photon Source (HEPS). In order to reduce the bunch charge requirement to the injector, high-energy accumulation in the HEPS booster is proposed to combine with the on-axis swap-out injection. This allows reducing the requirement of bunch charge accelerated in HEPS booster (500 MeV-6 GeV) from over 14.4 nC to about 5 nC. It is expected that the overall transmission efficiency during the low energy injection and ramping process of the booster should be higher than 80% to fulfill the requirement. In this paper, we present the simulation results of transmission efficiency and potential improvement measures.  
poster icon Poster MOPAB052 [0.362 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB052  
About • paper received ※ 13 May 2021       paper accepted ※ 26 May 2021       issue date ※ 15 August 2021  
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MOPAB053 Progress of Lattice Design and Physics Studies on the High Energy Photon Source lattice, injection, booster, impedance 229
 
  • Y. Jiao, Y. Bai, X. Cui, C.C. Du, Z. Duan, Y.Y. Guo, P. He, X.Y. Huang, D. Ji, H.F. Ji, S.C. Jiang, B. Li, C. Li, J.Y. Li, N. Li, X.Y. Li, P.F. Liang, C. Meng, W.M. Pan, Y.M. Peng, Q. Qin, H. Qu, S.K. Tian, J. Wan, B. Wang, J.Q. Wang, N. Wang, Y. Wei, G. Xu, H.S. Xu, F. Yan, C.H. Yu, Y.L. Zhao
    IHEP, Beijing, People’s Republic of China
  • X.H. Lu
    IHEP CSNS, Guangdong Province, People’s Republic of China
 
  Funding: Work supported by High Energy Photon Source (HEPS), a major national science and technology infrastructure and NSFC (11922512)
The High Energy Photon Source (HEPS) is a 34-pm, 1360-m storage ring light source being built in the suburb of Beijing, China. The HEPS construction started in mid-2019. While the physics design has been basically determined, modifications on the HEPS accelerator physics design have been made since 2019, in order to deal with challenges emerging from the technical and engineering designs. In this paper, we will introduce the new storage ring lattice and injector design, and also present updated results of related physics issues, including impedance and collective effects, lattice calibration, insertion device effects, injection design studies, etc.
 
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB053  
About • paper received ※ 10 May 2021       paper accepted ※ 24 May 2021       issue date ※ 17 August 2021  
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MOPAB055 Generation of Coherent Attosecond X-ray Pulses in the Southern Advanced Photon Source laser, electron, emittance, photon 237
 
  • W. Liu, Y. Zhao
    IHEP CSNS, Guangdong Province, People’s Republic of China
  • Y. Jiao, S. Wang
    IHEP, Beijing, People’s Republic of China
 
  Southern Advanced Photon Source (SAPS) is a fourth-generation storage ring light source that has been considered for construction in Guangdong province of China, adjacent to the China Spallation Neutron Source. As a low-emittance storage ring, the natural emittance of SAPS is below 100 pm. One of the benefits is that the brightness is about 2 orders high than 3rd generation light sources. However, like many other storage ring-based light sources, the time resolution is limited by the electron bunch length in the range of picoseconds. In this work, we propose a new scheme for the generation of coherent attoseconds X-ray pulses with a high repetition rate in SAPS. A numerical demonstration of the scheme is presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB055  
About • paper received ※ 17 May 2021       paper accepted ※ 26 May 2021       issue date ※ 26 August 2021  
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MOPAB061 Comparison Simulation Results of the Collimator Aperture in HEPS Storage Ring lattice, simulation, ECR, scattering 257
 
  • Y.L. Zhao, Y. Jiao, N. Li
    IHEP, Beijing, People’s Republic of China
 
  The High Energy Photon Source (HEPS) is a 6 GeV diffraction-limited storage ring light source, which is under construction and planned to be in operation in 2025. To protect the sensitive elements from being damaged and reduce the radiation level of the site, collimators will be installed in the storage ring to localize the particle losses. The Touschek scattering is the main cause of particle losses during daily nominal operations. Based on the elegant simulations, we evaluate the physical design of the collimators, especially analysis the collimator performance with different collimator apertures. The simulation results will be introduced in this paper.  
poster icon Poster MOPAB061 [0.701 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB061  
About • paper received ※ 13 May 2021       paper accepted ※ 17 August 2021       issue date ※ 21 August 2021  
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MOPAB063 Commissioning Strategy for Diamond-II MMI, lattice, optics, quadrupole 265
 
  • M. Apollonio, R.T. Fielder, H. Ghasem, I.P.S. Martin
    DLS, Oxfordshire, United Kingdom
 
  At Diamond Light Source we are working on the upgrade towards a machine aimed at a factor 20 reduction in emittance and an increase of the capacity for beamlines. Crucially the success of the programme depends on the ability to inject and capture the electrons in the storage ring, and finally reach control of beam alignment and the linear optics. The paper presents the series of strategies adopted to achieve the commissioning of the machine, from the threading procedure ensuring the first turn of the electron beam, to the orbit corrections in the storage ring. Beam based alignment of the quadrupoles and skew quadrupoles is illustrated and restoration of the linear optics (LOCO) for the storage ring is presented. Main performance parameters (Dynamic Apertures, Injection Efficiency and Lifetime) are calculated to evaluate the performance of the commissioned lattices.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB063  
About • paper received ※ 18 May 2021       paper accepted ※ 28 May 2021       issue date ※ 14 August 2021  
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MOPAB065 Optimization of the Lattice Replacement Options for the Next Generation Australian Synchrotron lattice, emittance, synchrotron, sextupole 269
 
  • R. Auchettl, R.T. Dowd, Y.E. Tan
    AS - ANSTO, Clayton, Australia
 
  The design of a next generation Australian Synchrotron replacement lattice is a multi-objective and multi-constrained problem. Our group was tasked to produce a low emittance design while re-using the existing tunnel infrastructure and injector system. Our objectives coupled with the set infrastructure constraints are not straightforward to achieve with manual design. Several variables act at cross-purposes to one-another, leading to a conflicting trade-off between objectives. Recently we have investigated replacement options for the Australian Synchrotron containing longitudinal gradient and reverse bends in the form of a 4BA (4-bend achromat) lattice. In this work, optimise the lattice design for a potential fourth generation Australian Synchrotron facility. We outline the baseline 4BA solution to the lowest emittance lattice that can reuse the existing tunnels and injector system.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB065  
About • paper received ※ 19 May 2021       paper accepted ※ 28 May 2021       issue date ※ 19 August 2021  
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MOPAB068 Collective Effects Studies for the SOLEIL Upgrade impedance, synchrotron, cavity, feedback 274
 
  • A. Gamelin, D. Amorim, P. Brunelle, W. Foosang, A. Loulergue, L.S. Nadolski, R. Nagaoka, R. Ollier, M.-A. Tordeux
    SOLEIL, Gif-sur-Yvette, France
 
  The SOLEIL upgrade project aims to replace the actual SOLEIL storage ring by a 4th generation light source. The project has just finished its conceptual design report (CDR) phase*. Compared to the SOLEIL storage ring, the upgraded storage ring design includes many new features of 4th generation light sources that will impact collective effects, such as reduced beam pipe apertures, a smaller momentum compaction factor and the presence of harmonic cavities (HC). To mitigate them, we rely on several damping mechanisms provided by the synchrotron radiation, the transverse feedback system, and the HC (Landau damping and bunch lengthening). This article presents a first estimate of the collective effects impact of the upgraded design.
* Conceptual Design Report: Synchrotron SOLEIL Upgrade, 2021, in press.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB068  
About • paper received ※ 17 May 2021       paper accepted ※ 02 June 2021       issue date ※ 12 August 2021  
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MOPAB069 Equilibrium Bunch Density Distribution with Multiple Active and Passive RF Cavities cavity, beam-loading, impedance, synchrotron 278
 
  • A. Gamelin
    SOLEIL, Gif-sur-Yvette, France
  • N. Yamamoto
    KEK, Ibaraki, Japan
 
  This paper describes a method to get the equilibrium bunch density distribution with an arbitrary number of active or passive RF cavities in uniform filling. This method is an extension of the one presented by M. Venturini which assumes a passive harmonic cavity and no beam loading in the main RF cavity*.
*M. Venturini, "Passive higher-harmonic rf cavities with general settings and multibunch instabilities in electron storage rings," Physical Review Accelerators and Beams, 2018.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB069  
About • paper received ※ 17 May 2021       paper accepted ※ 23 June 2021       issue date ※ 23 August 2021  
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MOPAB071 Progress with the Booster Design for the Diamond-II Upgrade booster, injection, emittance, extraction 286
 
  • I.P.S. Martin, C. Christou, M.P. Cox, R.T. Fielder, J. Kallestrup, A. Shahveh, W. Tizzano
    DLS, Oxfordshire, United Kingdom
  • A.D. Brynes, J.K. Jones, B.D. Muratori, H.L. Owen
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  Efficient injection into the Diamond-II storage ring [*, **] will require an emittance and bunch length substantially below the values produced from the existing booster. Whilst an earlier design for a replacement based on TME cells was able to meet the target values of <30 nm.rad and <40 ps respectively [***, ****], several technical constraints have led to a rethink of this solution. The revised booster lattice utilises a larger number of cells based on combined-function magnets with lower peak fields that still meets the emittance and bunch length goals. In addition, the new ring has been designed to have low impedance to maximise the extracted charge per shot. In this paper we describe the main features of the lattice, present the status of the engineering design and quantify the expected performance.
*Diamond-II Conceptual Design Report, Diamond Light Source
**H. Ghasem et al, these proceedings
***I. Martin, R. Bartolini, J.Phys.:Conf. Ser., 1067, 032005
****I. Martin et al, IPAC 2019, WEPMP042
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB071  
About • paper received ※ 18 May 2021       paper accepted ※ 31 May 2021       issue date ※ 02 September 2021  
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MOPAB072 Single-Bunch Thresholds for the Diamond-II Storage Ring impedance, cavity, simulation, beam-loading 290
 
  • T. Olsson, R.T. Fielder
    DLS, Oxfordshire, United Kingdom
 
  The proposed Diamond Light Source upgrade will see the storage ring replaced with a multibend achromat lattice, increasing the capacity of the facility whilst reducing the emittance and providing higher brightness for the users. As part of the design work, tracking studies have been performed to determine the single-bunch thresholds including both the resistive-wall and geometric contributions to the impedance. As the machine design also foresees a third order harmonic cavity, the paper also provides an initial assessment of the effects of bunch lengthening on the single-bunch thresholds.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB072  
About • paper received ※ 18 May 2021       paper accepted ※ 01 June 2021       issue date ※ 23 August 2021  
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MOPAB075 Proposal of the Southern Advanced Photon Source and Current Physics Design Study photon, linac, lattice, emittance 300
 
  • S. Wang, J. Chen, L. Huang, Y. Jiao, B. Li, Z.P. Li, W. Liu, S.Y. Xu
    IHEP, Beijing, People’s Republic of China
  • Y. Han, X.H. Lu, Y. Zhao
    IHEP CSNS, Guangdong Province, People’s Republic of China
  • X. Liu
    Department of Energy Sciences, Tokyo Institute of Technology, Yokohama, Japan
 
  It has been considered to build a mid-energy fourth-generation storage ring light source neighbouring the China Spallation Neutron Source, in Guangdong Province, the south of China. The light source is named the Southern Advanced Photon Source (SAPS). Preliminary physics design studies on the SAPS have been implemented for a few years. In this paper, we will describe considerations of technical roadmap and key parameter choice for this light source, and introduce the up-to-date lattice designs and related physics studies on the SAPS.  
poster icon Poster MOPAB075 [1.689 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB075  
About • paper received ※ 12 May 2021       paper accepted ※ 20 May 2021       issue date ※ 21 August 2021  
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MOPAB081 Feasibility Study of Using Multipole Injection Kicker (MIK) and Sextupole for TPS Injection injection, sextupole, kicker, GUI 312
 
  • C.-S. Fann, C.K. Chan, C.-C. Chang, H.-P. Chang, Y.-S. Cheng, M.-S. Chiu, Y.L. Chu, K.T. Hsu, S.Y. Hsu, K.H. Hu, J.C. Huang, C.-S. Hwang, S.H. Lee, K.-K. Lin, C.Y. Wu, C.S. Yang
    NSRRC, Hsinchu, Taiwan
  • S.-Y. Lee
    Indiana University, Bloomington, Indiana, USA
 
  Feasibility of applying MIK/sextupole injection at TPS is evaluated in this study. This study adopts layout similar to MAX IV injection scheme and their collaboration project with SOLEIL for MIK. Although the light source service fulfills present user needs, yet the increasing demands for a transparent injection is inevitable in the foreseeable future. Notice that this preliminary study is constrained under routine user operation, the optional pinger ceramic chamber, located between existing injection kicker-3 and kicker-4, is chosen for the purpose. Kick strength requirement of the MIK is estimated with minor trajectory adjustment upstream at the booster to storage ring transfer line. Since the realization of MIK fabrication takes time, therefore a fast-built sextupole is prepared to examine the proposed injection scheme beforehand. The test result will be described in this report.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB081  
About • paper received ※ 17 May 2021       paper accepted ※ 20 May 2021       issue date ※ 21 August 2021  
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MOPAB089 Effect of Different Models of Combined-function Dipoles on the HEPS Parameters dipole, lattice, quadrupole, emittance 335
 
  • Y.Y. Guo, Y. Jiao, N. Li
    IHEP, Beijing, People’s Republic of China
 
  The high energy photon source (HEPS) is a 6 GeV, kilometer-scale storage ring light source being built in Beijing, China. In the current ring lattice, the combined-function dipoles are used and assumed to have constant dipole field. However, in the actual magnet design, an eccentrically placed quadrupole is adopted, in which the bending field along the trajectory is not constant. In this paper, we will present the effect of the two models of combined-function dipoles on the parameters of the storage ring.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB089  
About • paper received ※ 13 May 2021       paper accepted ※ 25 May 2021       issue date ※ 27 August 2021  
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MOPAB091 Injection Section Upgrading with the Septum-Magnet Replacement in KEK-PF Ring injection, septum, vacuum, operation 342
 
  • C. Mitsuda, K. Harada, N. Higashi, T. Honda, Y. Kobayashi, H. Miyauchi, S. Nagahashi, N. Nakamura, T. Nogami, T. Obina, M. Tadano, R. Takai, H. Takaki, Y. Tanimoto, T. Uchiyama, A. Ueda
    KEK, Ibaraki, Japan
 
  In 2015, the water leakage happened at the cooling pipe of the in-vacuum septum magnet installed into the injection point. Because the maintenance of the leakage needed the total replacement of the magnet, the water circulation was stopped permanently, and accordingly, the light absorber was installed upstream in the storage ring to prevent the synchrotron light of the bending magnet from coming to the septum wall. This treatment temporally worked well, but the beam injection efficiency was decreased to about 30% due to the physical aperture narrowed by the absorber. With the desired replacement of septum magnet to maintainable out-vacuum type, the injection section upgrading was simultaneously planned to recover and improve the injection efficiency. In this upgrade, the injection beam is closed to the stored beam more than before by adapting the thinner septum structure as a way to improve the injection efficiency. And some new ideas are introduced in the part of monitor and beam duct, for example, realtime beam monitor, thinner Inconel duct. The detailed design of the upgraded injection section and technical points will be reviewed in this conference.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB091  
About • paper received ※ 19 May 2021       paper accepted ※ 26 May 2021       issue date ※ 02 September 2021  
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MOPAB092 Project of Wuhan Photon Source cavity, injection, linac, dipole 346
 
  • H.H. Li, Y. Deng, J.H. He, Y. Nie, L. Tang, J. Wang, Y.X. Zhu
    IAS, Wuhan City, People’s Republic of China
 
  Wuhan Photon Source (WHPS) has been designed as a fourth-generation light source, which consists of a low energy storage ring (1.5 GeV), a medium energy storage ring (4.0 GeV), and a linac working as a full energy injector. It has been planned to build the low energy light source first as the Phase I project, and then the medium energy light source after its completion. The low energy storage ring has been optimized with the main design parameters as following: An 8-cell, 500 mA storage ring, with a circumference of 180 m and nature emittance 238.4 pm-rad. Based on hybrid-7BA lattice structure, it reaches the soft X-ray diffraction limit. And at the middle of each cell, a 3.5 T superB magnet is used to extend the photon energy to the hard X-ray region. The swap-out injection is chosen due to the small dynamic aperture and a full energy S-band LINAC will be used as its injector. A 3rd harmonic cavity is designed for bunch lengthening to keep a sufficient lifetime. More details of the WHPS phase I project will be described in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB092  
About • paper received ※ 10 June 2021       paper accepted ※ 23 June 2021       issue date ※ 24 August 2021  
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MOPAB095 Concept Design for the CLS2 Accelerator Complex electron, emittance, synchrotron, lattice 354
 
  • M.J. Boland, P.J. Hunchak
    University of Saskatchewan, Saskatoon, Canada
  • C.K. Baribeau, D. Bertwistle, J.M. Patel, H. Shaker, X. Shen, M.J. Sigrist
    CLS, Saskatoon, Saskatchewan, Canada
  • F. Le Pimpec
    EuXFEL, Schenefeld, Germany
  • E.J. Wallén
    LBNL, Berkeley, California, USA
 
  The Canadian Light Source has been in operation since 2005 and is now looking at a design concept to upgrade to a fourth generation storage ring. A brief overview is given of a possible accelerator complex layout, including some details on the lattice design and injection system. A full energy linac is being explored as an option for top-up injection and to future proof the facility for a potential FEL upgrade in the future.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB095  
About • paper received ※ 23 May 2021       paper accepted ※ 28 July 2021       issue date ※ 13 August 2021  
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MOPAB102 CSR Impedance in HEPS Storage Ring impedance, lattice, synchrotron, vacuum 379
 
  • H.S. Xu, X.Y. Li, N. Wang
    IHEP, Beijing, People’s Republic of China
 
  High Energy Photon Source (HEPS) is under construction in Beijing, China. The relatively complete impedance model has been built up based on the element-by-element impedance calculation. However, Coherent Synchrotron Radiation (CSR) impedance, which might affect the longitudinal performance of the beam, was not included in the impedance model of the HEPS storage ring in the preliminary design stage. For completeness, we would like to take the CSR impedance into consideration. The most important contributions to the total CSR impedance come from the bending magnets and insertion devices. We therefore calculate the CSR impedance from both above mentioned elements in HEPS storage ring. The influence of the CSR impedance on the microwave instability threshold is studied and presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB102  
About • paper received ※ 17 May 2021       paper accepted ※ 18 June 2021       issue date ※ 27 August 2021  
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MOPAB103 Study of Transverse Oscillation Coupling and Possibility of Its Minimization in SKIF (Novosibirsk) coupling, quadrupole, emittance, sextupole 383
 
  • D. Leshenok
    BINP, Novosibirsk, Russia
  • G.N. Baranov, E.B. Levichev, S.A. Nikitin
    BINP SB RAS, Novosibirsk, Russia
 
  The vertical emittance and, in general, the vertical beam size and angular divergence are of paramount importance in the SKIF (Russian acronym for Siberian Circular Photon Source) project developed in Novosibirsk. Therefore, a detailed simulation of the corresponding influence of possible errors in the storage ring was carried out with cross-validation by different methods. Variants of cross-coupling correction are proposed and modeled to obtain a vertical emittance of the order of one picometer simultaneously with minimizing vertical dispersion.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB103  
About • paper received ※ 18 May 2021       paper accepted ※ 17 August 2021       issue date ※ 19 August 2021  
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MOPAB106 Enhancing the MOGA Optimization Process at ALS-U with Machine Learning lattice, dynamic-aperture, emittance, sextupole 387
 
  • Y. Lu, M.P. Ehrlichman, T. Hellert, S.C. Leemann, H. Nishimura, C. Sun, M. Venturini
    LBNL, Berkeley, California, USA
 
  Funding: This research is funded by the US Department of Energy(BES & ASCR Programs), and supported by the Director of the Office of Science of the US Department of Energy under Contract No. DEAC02-05CH11231.
The bare lattice optimization for the linear and nonlinear ALS-U storage ring lattice, even without reverse bending, comprises 11 degrees of freedom (DoF) and is therefore a very complex and highly time-consuming process. This design process relies heavily on multi-objective genetic algorithms (MOGA), usually requiring many months of experienced scientists’ time. The main problem lies in having to evaluate numbers of candidate lattices due to the stochastic process of MOGA. Although almost all of these candidates are eventually rejected, they nevertheless require extensive particle tracking to arrive at a Pareto front. We therefore propose a novel Machine Learning (ML) pipeline that nonlinear tracking is replaced by two well-trained neural networks (NNs) to predict dynamic aperture (DA) and momentum aperture (MA) for any lattice candidate. Initial training of these models takes only several minutes on conventional CPUs while predictions are then rendered near instantaneously. We present this novel method and demonstrate the resulting orders of magnitude speedup of the ML-enhanced MOGA process on a 2-DoF problem as well as first results on a more complex 11-DoF problem.
 
poster icon Poster MOPAB106 [0.918 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB106  
About • paper received ※ 19 May 2021       paper accepted ※ 01 June 2021       issue date ※ 18 August 2021  
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MOPAB112 A Modified Hybrid 6BA Lattice for the HALF Storage Ring lattice, emittance, damping, SRF 407
 
  • Z.H. Bai, G.Y. Feng, T.L. He, W. Li, W.W. Li, G. Liu, Z.L. Ren, L. Wang, P.H. Yang, S.C. Zhang, T. Zhang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  In this paper, we propose a modified hybrid 6BA lattice as the baseline lattice of the Hefei Advanced Light Facility (HALF) storage ring. Similar to the Diamond-II lattice, the proposed lattice cell has one long straight section and one mid-straight section; but the two bend units adjacent to the mid-straight are LGB/RB units (LGB: longitudinal gradient bend, RB: reverse bend), which can give both lower emittance and shorter damping times. The designed HALF storage ring, with an energy of 2.2 GeV and 20 lattice cells, has a natural emittance of about 85 pm·rad.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB112  
About • paper received ※ 15 May 2021       paper accepted ※ 20 May 2021       issue date ※ 01 September 2021  
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MOPAB113 A Low-emittance Booster Lattice Design for the SOLEIL Upgrade booster, lattice, emittance, linear-dynamics 410
 
  • M.-A. Tordeux, A. Loulergue, R. Nagaoka
    SOLEIL, Gif-sur-Yvette, France
  • Z.H. Bai, G. Liu, T. Zhang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  The SOLEIL storage ring upgrade will require an injected beam with small transverse and longitudinal sizes. To meet this requirement, the present booster also needs to be upgraded, aiming to reduce the emittance below 10 nm·rad. A multi-bend achromat lattice is designed in this context for the booster upgrade, which consists of two superperiods to respect the present race-track configuration. The lattice is a 16BA HOA (Higher-Order Achromat) type lattice, composed of 14 unit cells, 2 matching cells and a long straight section, and combined-function bending magnets are used in the unit cells to both save space and reduce the emittance. The natural emittance of the designed booster is 5.2 nm·rad at the final energy of 2.75 GeV. This paper presents the general constraints, linear lattice design and nonlinear dynamics optimization for the booster upgrade.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB113  
About • paper received ※ 19 May 2021       paper accepted ※ 28 May 2021       issue date ※ 26 August 2021  
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MOPAB114 Development of a Decoherence Kicker for the ALS Upgrade Project (ALS-U) kicker, extraction, vacuum, injection 414
 
  • C. Sun, S. De Santis, M.P. Ehrlichman, T. Hellert, T. Oliver, G. Penn, C. Steier, M. Venturini, W.L. Waldron
    LBNL, Berkeley, California, USA
 
  The Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory is upgrading the existing storage-ring lattice to a nine-bend-achromat lattice with on-axis swap-out injection. The upgraded storage ring will provide a highly focused beam of about 10 um in both horizontal and vertical directions with a single bunch train energy of about 60 J at 2.0 GeV. Such a small and intense beam could cause damage to the transfer line vacuum chambers in case of extraction element failures or damage to the storage ring vacuum chamber in case of RF failures. To mitigate these potential damages, a fast kicker magnet (so-called decoherence kicker) will be installed in the ALS-U storage ring and activated to dilute the beam charge density either on a train to be swapped out a few 100s turns before extraction or on the whole beam after RF failures. In this paper, we will present both physics and engineering designs of this decoherence kicker.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB114  
About • paper received ※ 19 May 2021       paper accepted ※ 27 May 2021       issue date ※ 20 August 2021  
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MOPAB115 ATS/STA Transfer Line Design for the ALS Upgrade Project (ALS-U) injection, kicker, optics, extraction 417
 
  • C. Sun, M.P. Ehrlichman, T. Hellert, M. Juchno, J.-Y. Jung, M. Mardenfeld, J.R. Osborn, G. Penn, C. Steier, C.A. Swenson, M. Venturini
    LBNL, Berkeley, California, USA
 
  At the Advanced Light Source Upgrade (ALS-U), an on-axis swap-out injection will be used to replenish depleted bunches in the storage ring with refreshed bunches from the full energy accumulator ring. To implement this scheme, two transfer lines are required between the storage ring and the accumulator ring: the accumulator-to-storage-ring (ATS) transfer line and the storage-ring-to-accumulator (STA) transfer line. The design of the ATS/STA transfer lines is a challenging task as they must fit within a tight injection region while also accommodating the storage and accumulator rings at different elevations. Moreover, the ATS/STA design needs to meet both the boundary conditions and optics requirements. In this paper, we will present a design option for these ATS/STA transfer lines.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB115  
About • paper received ※ 19 May 2021       paper accepted ※ 27 May 2021       issue date ※ 15 August 2021  
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MOPAB116 A Flexible Injection Scheme for the ESRF-EBS injection, kicker, SRF, septum 421
 
  • S.M. White, N. Carmignani, L.R. Carver, M. Dubrulle, L. Hoummi, S.M. Liuzzo, M. Morati, T.P. Perron
    ESRF, Grenoble, France
 
  The ESRF-EBS storage ring light source started commissioning in 2019 and successfully resumed users operation in 2020. Due to the smaller emittance and consequently reduced lifetime frequent injections are required that can potentially disturb beam lines experiments. In addition, operating the machine with low beta straight section and reduced insertion devices (ID) gaps are considered, therefore reducing the vertical aperture of the machine. Alternatives to the standard off-axis injection scheme allowing for efficient injection in reduced apertures with minimized perturbations are explored. A flexible layout for potential integration in the ESRF-EBS lattice is proposed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB116  
About • paper received ※ 11 May 2021       paper accepted ※ 27 May 2021       issue date ※ 24 August 2021  
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MOPAB120 Update on Injector for the New Synchrotron Light Source in Thailand linac, synchrotron, injection, photon 435
 
  • T. Chanwattana, S. Chunjarean, N. Juntong, K. Kittimanapun, S. Klinkhieo, P. Sudmuang
    SLRI, Nakhon Ratchasima, Thailand
  • K. Manasatitpong
    Synchrotron Light Research Institute (SLRI), Muang District, Thailand
 
  Design of the new 3-GeV synchrotron light source in Thailand, Siam Photon Source II (SPS-II), has been updated. The SPS-II accelerator complex consists of a 150-MeV injector linac, a 3-GeV booster synchrotron and a 3-GeV storage ring. The RF system of both storage ring and booster is based on a frequency of 119 MHz. In this paper, design considerations and specifications of the SPS-II injector linac are presented. A study on the injector linac in multi-bunch mode (MBM) and single-bunch mode (SBM) was done to get appropriate parameters for top-up injection and different filling patterns in the storage ring.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB120  
About • paper received ※ 18 May 2021       paper accepted ※ 20 May 2021       issue date ※ 24 August 2021  
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MOPAB122 Present Status of HiSOR synchrotron, injection, undulator, radiation 442
 
  • M. Katoh
    UVSOR, Okazaki, Japan
  • K. Goto, M. Katoh, M. Shimada
    HSRC, Higashi-Hiroshima, Japan
  • H. Miyauchi
    KEK, Ibaraki, Japan
 
  HiSOR is a compact synchrotron light source of 700MeV. The circumference is 22m. The ring has two straight sections for undulators, which provide high brilliance VUV radiation. Two 180 bending magnets have 2.7 T field strength, which provide broadband radiation in VUV and soft X-ray range. The injector is a 150 MeV microtron. The beam injection is made twice a day with a 5 hour interval. Although the accelerators are being operated stably, the large emittance of 400nm makes it difficult to compete with high brilliance light sources of new generations. The compactness of the configuration makes it difficult to introduce new technologies. We have started seeking possible upgrades.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB122  
About • paper received ※ 18 May 2021       paper accepted ※ 20 May 2021       issue date ※ 30 August 2021  
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MOPAB128 Operational Use of Pinger Magnets to Counter Stored Beam Oscillations During Injection at Diamond Light Source injection, kicker, operation, diagnostics 459
 
  • R.T. Fielder, M. Apollonio, I.P.S. Martin
    DLS, Oxfordshire, United Kingdom
 
  Diamond uses a four kicker bump injection scheme. Due to a variety of factors it has become more difficult to perfectly match the four kicks while maintaining injection efficiency, resulting in some disturbance to the stored beam during top-up. This has consequences for beamlines which may see degraded beam quality during injections. A gating signal is provided, but this is not appropriate for all experiments, and in any case ideally would not be required. The disturbance to the stored beam can be partly controlled using the existing diagnostic pinger magnets installed in the storage ring. We present here a comparison of different compensation schemes and tests with beamlines, along with initial experiences operating during user beam time. Use of these magnet also provides proof of principle for any future, purpose-built compensation kickers.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB128  
About • paper received ※ 18 May 2021       paper accepted ※ 20 May 2021       issue date ※ 01 September 2021  
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MOPAB214 Linear Optics Measurement for the APS Ring with Turn-by-Turn BPM Data optics, quadrupole, lattice, betatron 707
 
  • X. Huang, V. Sajaev, Y.P. Sun, A. Xiao
    ANL, Lemont, Illinois, USA
 
  We measure the linear optics of the APS storage ring from turn-by-turn BPM data taken when the beam is excited with an injection kicker. Decoherence due to chromaticity and amplitude-dependent detuning is observed and compared to theoretic predictions. Independent component analysis is used to analyze the data, which separates the betatron normal modes and synchrotron motion, despite contamination of bad BPMs. The beta functions and phase advances are subsequently obtained. The method is used to study the linear optics perturbation of an insertion device.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB214  
About • paper received ※ 12 May 2021       paper accepted ※ 09 June 2021       issue date ※ 01 September 2021  
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MOPAB225 A HMBA Lattice Design Study for the 4 GeV Light Source lattice, emittance, dipole, sextupole 734
 
  • S.W. Jang, E.-S. Kim
    KUS, Sejong, Republic of Korea
 
  The 4th generation storage ring (4GSR) project will start from 2022 in South Korea. We proposed HMBA (Hybrid Multi-Bend Achromatic) lattice for 4GSR with super-bend at the center of the lattice. The 4GSR lattice is designed to combined HMBA lattice with a 4 GeV, 53 pm-rad emittance and 843m. The storage ring including 32 long with 5.65m, 16 short straight with 1.3m sections for IDs and 16 super-bend sections for more different type of beam line experiments. A calculated dynamic aperture is more larger than 15mm in both direction and the beam life time is expected to 4.7 hour. In this paper, we will describe the study results of the HMBA lattice design with a 4GeV light source.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB225  
About • paper received ※ 20 May 2021       paper accepted ※ 24 May 2021       issue date ※ 30 August 2021  
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MOPAB226 Analytical Description of the Steerer Parameters in the Bilinear-Exponential Model at DELTA betatron, closed-orbit, coupling, simulation 737
 
  • S. Kötter
    DELTA, Dortmund, Germany
 
  At DELTA, a 1.5 GeV synchrotron radiation source operated by the TU Dortmund University, an analytical description of the steerer parameters in the bilinear-exponential (BE) model has been developed. The BE model describes the coupled orbit response in a storage ring. It is used in the closed-orbit bilinear-exponential analysis (COBEA) algorithm to decompose orbit response matrices into beta function, betatron phase, and a scaled dispersion. After introducing the BE model and the analytical steerer parameters, a simulation-based comparison of the BE model and another coupled orbit response model is presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB226  
About • paper received ※ 19 May 2021       paper accepted ※ 08 June 2021       issue date ※ 11 August 2021  
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MOPAB228 Introducing two Energy-Correction Schemes at DELTA operation, simulation, closed-orbit, injection 740
 
  • S. Kötter
    DELTA, Dortmund, Germany
 
  At DELTA, a 1.5 GeV synchrotron light source operated by the TU Dortmund University, two methods to correct the beam energy of the storage ring have been tested. The first one is capable of maintaining the current beam energy. The second method is used to find the optimal orbit length. Here, the ideas behind both methods are explained and first test results are presented. Numerical studies are shown together with measurement results.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB228  
About • paper received ※ 19 May 2021       paper accepted ※ 02 June 2021       issue date ※ 29 August 2021  
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MOPAB235 Transverse 2d Phase-Space Tomography Using Beam Position Monitor Data of Kicked Beams emittance, optics, electron, betatron 763
 
  • K. Hwang, C.E. Mitchell, R.D. Ryne
    LBNL, Berkeley, California, USA
 
  Funding: U.S. Department of Energy under Contract No. DE-AC02-05CH11231
The time-series Beam Position Monitor (BPM) data of kicked beam is a function of lattice parameters and beam parameters including phase-space density. The decoherence model using the first-order detuning parameter has an exact solution when the beam is Gaussian. We parameterize the beam phase-space density by multiple Gaussian kernels of different weights, means, and sizes to formulate the inverse problem for 2D phase-space tomography. Numerical optimization and Bayesian inference are used to infer the beam density.
 
poster icon Poster MOPAB235 [1.253 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB235  
About • paper received ※ 20 May 2021       paper accepted ※ 02 June 2021       issue date ※ 01 September 2021  
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MOPAB239 Simulation and Optimization of the Spin Coherence Time of Protons in a Prototype EDM Ring quadrupole, dipole, simulation, polarization 771
 
  • M. Vitz, A. Lehrach
    FZJ, Jülich, Germany
  • R. Shankar
    INFN-Ferrara, Ferrara, Italy
 
  The matter-antimatter asymmetry might be understood by investigating the EDM (Electric Dipole Moment) of elementary charged particles. A permanent EDM of a subatomic particle violates time-reversal and parity symmetry at the same time and would be, with the currently achievable experimental accuracy, a strong indication for physics beyond the Standard Model. The JEDI-Collaboration (Jülich Electric Dipole moment Investigations) in Jülich is preparing a direct EDM measurement for protons and deuterons: first at the storage ring COSY (COoler SYnchrotron) and later at a dedicated storage ring. A prototype EDM ring is an intermediate step before building the final storage ring to demonstrate sufficient beam lifetime and SCT (Spin Coherence Time) in a pure electrostatic ring as well as in a storage ring with combined electric and magnetic bending elements. In order to study the effect of E-B-deflectors on the orbit and the spin motion, the software library Bmad is used. The first results of the optics and spin simulations, with a focus on the optimization of the SCT, towards the prototype EDM ring will be discussed.  
poster icon Poster MOPAB239 [0.560 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB239  
About • paper received ※ 17 May 2021       paper accepted ※ 09 June 2021       issue date ※ 23 August 2021  
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MOPAB240 Estimates of Damped Equilibrium Energy Spread and Emittance in a Dual Energy Storage Ring emittance, damping, photon, radiation 774
 
  • B. Dhital, G.A. Krafft
    ODU, Norfolk, Virginia, USA
  • Y.S. Derbenev, D. Douglas, A. Hutton, G.A. Krafft, F. Lin, V.S. Morozov, Y. Zhang
    JLab, Newport News, Virginia, USA
 
  Funding: Work supported by the U.S. Department of Energy, Office of Science, and Office of Nuclear Physics under Contracts DE-AC05-06OR23177 and DE-AC02-06CH11357. / Jefferson Lab EIC Fellowship2020.
A dual energy storage ring design consists of two loops at markedly different energies. As in a single-energy storage ring, the linear optics in the ring design may be used to determine the damped equilibrium emittance and energy spread. Because the individual radiation events in the two rings are different and independent, we can provide analytical estimates of the damping times in a dual energy storage ring. Using the damping times, the values of damped energy spread, and emittance can be determined for a range of parameters related to lattice design and rings energies. We present analytical calculations along with simulation results to estimate the values of damped energy spread and emittance in a dual energy storage ring. We note that the damping time tends to be dominated by the damping time of the high energy ring in cases where the energy of the high energy rings is significantly greater than that of the low energy ring.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB240  
About • paper received ※ 17 May 2021       paper accepted ※ 27 May 2021       issue date ※ 13 August 2021  
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MOPAB242 A Six-Bend-Achromat Lattice for a 2.5 GeV Diffraction-Limited Storage Ring lattice, quadrupole, emittance, dipole 782
 
  • J. Li, M. Abo-Bakr, P. Goslawski
    HZB, Berlin, Germany
  • Z.H. Bai
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  HZB has proposed a 2.5 GeV diffraction-limited storage ring as the upgrade of BESSY II. A Six-Bend-Achromat lattice based on Higher-Order Achromat, as one of the possible solutions, has been designed to meet the requirements of low emittance, compact layout, large dynamic aperture and large momentum acceptance. The linear lattice design and the nonlinear performance are presented in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB242  
About • paper received ※ 18 May 2021       paper accepted ※ 09 June 2021       issue date ※ 17 August 2021  
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MOPAB248 Injection Schemes for the SOLEIL Upgrade injection, lattice, betatron, synchrotron 796
 
  • M.-A. Tordeux, P. Alexandre, R. Ben El Fekih, P. Brunelle, L. Hoummi, A. Loulergue, L.S. Nadolski, R. Nagaoka
    SOLEIL, Gif-sur-Yvette, France
 
  Injection into the SOLEIL upgrade storage ring is much more challenging compared to the case of the current ring. Thanks to the experience gained in the development, manufacture and commissioning of a Multipole Injection Kicker (MIK) on the MAX IV 3 GeV storage ring, the SOLEIL pulsed magnet team is currently developing new MIK magnets that will serve as the basis for the injection schemes in the upgrade storage ring. We then propose two kinds of injections: firstly, a betatron off-axis injection that should be compatible with the full-coupling storage ring tuning, and secondly, a synchrotron on-axis injection by creating a large horizontal dispersion bump at the injection point.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB248  
About • paper received ※ 19 May 2021       paper accepted ※ 21 May 2021       issue date ※ 26 August 2021  
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MOPAB254 Measurement of Horizontal Beam Size Using Sextupole Magnets sextupole, quadrupole, positron, dipole 802
 
  • J.A. Crittenden, K.E. Deitrick, H.X. Duan, G.H. Hoffstaetter, V. Khachatryan, D. Sagan
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: This work is supported by National Science Foundation award number DMR-1829070.
The quadratic dependence of sextupole fields on position results in a beam-size-dependent kick on a beam traversing a sextupole magnet. A change in sextupole strength changes the closed orbit and the tune of the beam in a storage ring. Measuring both therefore allows conclusions about the beam size in the sextupole. Here we derive the pertinent formula and discuss the applicability to storage rings. In particular we investigate the measurement accuracy that can be achieved at the Cornell High Energy Synchrotron Source. The Cornell Electron-positron Storage Ring underwent a major upgrade in 2018 with the goal of reducing the emittance by a factor of four. A variety of beam size measurement methods have been developed to monitor the positron beam size, including visible synchrotron light and interferometry. We investigate the sensitivity of the sextupole method and compare to other measurement techniques. The design horizontal emittance of the 6-GeV positron beam is about 30 nm-rad with typical beam sizes of about 1 mm, setting the scale for the required accuracy in the beam-size measurement.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB254  
About • paper received ※ 19 May 2021       paper accepted ※ 22 June 2021       issue date ※ 01 September 2021  
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MOPAB260 Optics Corrections with LOCO on Sirius Storage Ring quadrupole, optics, coupling, MMI 825
 
  • M.B. Alves
    LNLS, Campinas, Brazil
 
  Sirius is a 4th generation 3GeV synchrotron light source at the Brazilian Center for Research in Energy and Materials (CNPEM). In this work, we report the results of linear optics and coupling corrections during the commissioning of Sirius storage ring, using the Linear Optics from Closed Orbits (LOCO) algorithm. Beam-based measurements were performed to verify independently the impact of corrections on storage ring parameters.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB260  
About • paper received ※ 19 May 2021       paper accepted ※ 02 June 2021       issue date ※ 30 August 2021  
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MOPAB261 NSLS-II Storage Ring Lattice Analysis using Response Matrices lattice, quadrupole, alignment, sextupole 829
 
  • J. Choi
    BNL, Upton, New York, USA
 
  Funding: Work supported by the U.S. Department of Energy (DOE) under contract No. DE-SC0012704.
Affected from various sources, the NSLS-II storage ring lattice is slightly changing operation to operation and, for the operational performance, we are continually optimizing the lattice and maintaining the response matrices for the feedback and lattice analysis. Because not all sources are identified, we are investing efforts to identify as many as possible. As one of such efforts, we also study the measured response matrices. In this paper, we present the results of lattice studies using a pair of recently measured response matrices.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB261  
About • paper received ※ 20 May 2021       paper accepted ※ 02 June 2021       issue date ※ 19 August 2021  
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MOPAB275 Study on Supports of BPM Displacement Measurement System for HLS simulation, acceleration, factory, feedback 870
 
  • C.H. Wang, P. Lu, B.G. Sun, T.Y. Zhou
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  Funding: National Synchrotron Radiation Laboratory
HLS is the second-generation light source with energy of 800 MeV and emittance of less than 40 nm-rad. In order to improve the beam orbit stability and correct the errors introduced in the orbital feedback system due to movement of the vacuum chamber and BPM, a system for measuring BPM displacement will be built. It requires a high degree of mechanical and thermal stability for its supports. The support should have a higher eigen-frequency to minimize the amplification of ground vibration. In this paper, a series of simulation, including finite element analysis (FEA), measurement and analysis have been done upon the support to make sure it can meet the requirements of the stability of the BPM displacement measurement system.
 
poster icon Poster MOPAB275 [1.025 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB275  
About • paper received ※ 18 May 2021       paper accepted ※ 21 May 2021       issue date ※ 26 August 2021  
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MOPAB293 Electro-Optical Diagnostics at KARA and FLUTE - Results and Prospects diagnostics, electron, laser, experiment 927
 
  • G. Niehues, E. Bründermann, M. Caselle, S. Funkner, A.-S. Müller, M.J. Nasse, M.M. Patil, R. Ruprecht, M. Schuh, M. Weber, C. Widmann
    KIT, Karlsruhe, Germany
 
  Funding: S.F. was funded by BMBF contract No. 05K16VKA, C. W. by BMBF contract number 05K19VKD. G.N. and E.B. acknowledge support by the Helmholtz President’s strategic fund IVF "Plasma Accelerators".
Electro-optical (EO) methods are nowadays well-proven diagnostic tools, which are utilized to detect THz fields in countless experiments. The world’s first near-field EO sampling monitor at an electron storage ring was developed and installed at the KIT storage ring KARA (Karlsruhe Research Accelerator) and optimized to detect longitudinal bunch profiles. This experiment with other diagnostic techniques builds a distributed, synchronized sensor network to gain comprehensive data about the phase-space of electron bunches as well as the produced coherent synchrotron radiation (CSR). These measurements facilitate studies of physical conditions to provide, at the end, intense and stable CSR in the THz range. At KIT, we also operate FLUTE (Ferninfrarot Linac- und Test-Experiment), a new compact versatile linear accelerator as a test facility for novel techniques and diagnostics. There, EO diagnostics will be implemented to open up possibilities to evaluate and compare new techniques for longitudinal bunch diagnostics. In this contribution, we will give an overview of results achieved, the current status of the EO diagnostic setups at KARA and FLUTE and discuss future prospects.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB293  
About • paper received ※ 19 May 2021       paper accepted ※ 07 July 2021       issue date ※ 17 August 2021  
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MOPAB294 Implementing Electro-Optical Diagnostics for Measuring the CSR Far-Field at KARA laser, radiation, detector, synchrotron 931
 
  • C. Widmann, E. Bründermann, M. Caselle, S. Funkner, A.-S. Müller, M.J. Nasse, G. Niehues, M.M. Patil, C. Sax, J.L. Steinmann, M. Weber
    KIT, Karlsruhe, Germany
  • C. Mai
    DELTA, Dortmund, Germany
 
  Funding: This work was supported by BMBF ErUM-Pro project 05K19 STARTRAC, C.W. was funded under contract No. 05K19VDK, C.M. under contract No. 05K19PEC, S.F. under contract No. 05K16VKA.
For measuring the temporal profile of the coherent synchrotron radiation (CSR) at the KIT storage ring KARA (Karlsruhe Research Accelerator) an experimental setup based on electro-optical spectral decoding (EOSD) is currently being implemented. The EOSD technique allows single-shot, phase-sensitive measurements of the far-field radiation on a turn-by-turn basis at rates in the MHz range. Therefore, the resulting THz radiation from the dynamics of the bunch evolution, e.g. the microbunching, can be observed with high temporal resolution. This far-field setup is part of the distributed sensor network at KARA. Additionally to the information acquired from the near-field EOSD spectral decoding and the horizontal bunch profile monitor, it enables to monitor the longitudinal phase-space of the bunch. In this contribution, the characterization of the far-field setup is summarized and its implementation is discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB294  
About • paper received ※ 19 May 2021       paper accepted ※ 07 June 2021       issue date ※ 18 August 2021  
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MOPAB296 Statistical Analysis of 2D Single-Shot PPRE Bunch Measurements photon, radiation, operation, diagnostics 939
 
  • M. Koopmans, J.-G. Hwang, A. Jankowiak, M. Ries, A. Schälicke, G. Schiwietz
    HZB, Berlin, Germany
 
  The pulse picking by resonant excitation (PPRE) method* is used to realize pseudo single-bunch radiation from a complex filling pattern at the BESSY II storage ring. The PPRE bunch is excited in the horizontal plane by a quasi-resonant incoherent perturbation to increase the emittance of this bunch**. Therefore, the synchrotron light of the PPRE bunch can be separated by collimation from the radiation of the main bunch train at dedicated beamlines for timing users. The properties of the PPRE bunch depend on the storage ring settings and on the excitation parameters. It is not trivial to distinguish between the wanted intrinsic bunch broadening and an additional position fluctuation of the PPRE bunch. Using the potential of the new diagnostics beamline with the possibility to observe an additional spatial dimension with a fast streak camera, we introduce a new method to study the properties of the PPRE bunch***. Applying a statistical analysis to a series of single-turn images enables distinguishing between horizontal orbit motion and the broadening of the bunch due to the excitation. Measurements are presented and the results are compared with data from the BPM system.
* K. Holldack et al., Nature Commun. 5 (2014) 4010.
** J.-G. Hwang et al., Nucl. Instrum. Methods A940 (2019) 387.
*** G. Schiwietz et al., Nucl. Instrum. Methods A990 (2021) 164992.
 
poster icon Poster MOPAB296 [2.074 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB296  
About • paper received ※ 19 May 2021       paper accepted ※ 02 June 2021       issue date ※ 23 August 2021  
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MOPAB303 Design of the X-Ray Beam Size Monitor for the Advanced Photon Source Upgrade emittance, electron, photon, detector 956
 
  • K.P. Wootton, F.K. Anthony, K. Belcher, J.S. Budz, J. Carwardine, W.X. Cheng, S. Chitra, G. Decker, S.J. Izzo, S.H. Lee, J. Lenner, Z. Liu, P. McNamara, H.V. Nguyen, F.S. Rafael, C. Roehrig, J. Runchey, N. Sereno, G. Shen, J.B. Stevens, B.X. Yang
    ANL, Lemont, Illinois, USA
 
  Funding: This research used resources of the Advanced Photon Source, operated for the U.S. Department of Energy Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
A beam size monitor provides an intuitive display of the status of the beam profile and motion in an accelerator. In the present work, we outline the design of the X-ray electron beam size monitor for the Advanced Photon Source Upgrade. Components and anticipated performance characteristics of the beam size monitor are outlined.
 
poster icon Poster MOPAB303 [0.577 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB303  
About • paper received ※ 18 May 2021       paper accepted ※ 02 June 2021       issue date ※ 24 August 2021  
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MOPAB327 Beam Loss Diagnostics System for SKIF Synchrotron Light Source simulation, electron, diagnostics, synchrotron 1012
 
  • X.C. Ma
    BINP, Novosibirsk, Russia
  • S.V. Ivanenko, E.A. Puryga
    Budker Institute of Nuclear Physics, Novosibirsk, Russia
  • A.D. Khilchenko, Yu.I. Maltseva, O.I. Meshkov
    BINP SB RAS, Novosibirsk, Russia
  • Yu.I. Maltseva, O.I. Meshkov
    NSU, Novosibirsk, Russia
 
  The Siberian ring photon source (SKIF) is a new generation synchrotron light source designed and built by the Budker Institute of Nuclear Physics. The beam loss diagnostics system is a tool for monitoring beam loss information. It is widely used in modern large accelerators to provide a basis for diagnosing and locating machine faults, optimizing and debugging working beam parameters, and improving beam lifetime. Two types of beam loss monitor (BLM) will be applied on SKIF: fiber-based Cherenkov beam loss monitor (CBLM) and scintillator-based BLM (SBLM). Multi-mode silica fibers CBLM will be installed on linear accelerator and transfer lines. 128 SBLMs will be placed around the storage ring, dynamic ranges and sophisticated electronic equipment are employed to cover different SKIF operating modes. This article represents the details of design of beam loss diagnostics of SKIF, introduces the simulation and experimental studies of CBLM and SBLM.  
poster icon Poster MOPAB327 [4.893 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB327  
About • paper received ※ 19 May 2021       paper accepted ※ 26 May 2021       issue date ※ 30 August 2021  
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MOPAB357 The New Design of the RF System for the SPS-II Light Source cavity, booster, impedance, linac 1110
 
  • N. Juntong, T. Chanwattana, S. Chunjarean, S. Krainara, T. Phimsen, T. Pulampong
    SLRI, Nakhon Ratchasima, Thailand
  • K. Manasatitpong
    Synchrotron Light Research Institute (SLRI), Muang District, Thailand
 
  The new light source facility in Thailand, SPS-II, is a ring-based 3 GeV light source with a circumference of approximately 330 m. The target stored beam current is 300 mA with an emittance of below 1.0 nm rad. The injector has been changed from a full energy linac to a booster injector with 150 MeV linac. The main RF frequency has been reconsidered to a low-frequency range at 119 MHz. Low frequency is chosen with the benefit of low RF voltage for a high RF acceptance together with experience with the present ring RF system of 118 MHz. Details of RF frequency consideration will be discussed. The requirements and details of the RF systems in the booster ring and the storage ring will be presented.  
poster icon Poster MOPAB357 [1.696 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB357  
About • paper received ※ 17 May 2021       paper accepted ※ 08 June 2021       issue date ※ 14 August 2021  
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MOPAB380 Status and Progress of the RF System for High Energy Photon Source cavity, photon, booster, low-level-rf 1165
 
  • P. Zhang, J. Dai, Z.W. Deng, L. Guo, T.M. Huang, D.B. Li, J. Li, Z.Q. Li, H.Y. Lin, Y.L. Luo, Q. Ma, F. Meng, Z.H. Mi, Q.Y. Wang, X.Y. Zhang, F.C. Zhao, H.J. Zheng
    IHEP, Beijing, People’s Republic of China
 
  Funding: This work was supported in part by High Energy Photon Source, a major national science and technology infrastructure in China and in part by the Chinese Academy of Sciences.
High Energy Photon Source (HEPS) is a 6 GeV diffraction-limited synchrotron light source currently under construction in Beijing. It adopts a double-frequency RF system with 166.6 MHz as fundamental and 499.8 MHz as third harmonic. The fundamental cavity is making use of a superconducting quarter-wave β=1 structure and the third harmonic is of superconducting elliptical single-cell geometry for the storage ring, while normal-conducting 5-cell cavities are chosen for the booster ring. A total of 900 kW RF power shall be delivered to the beam by the 166.6 MHz cavities and the third harmonic cavities are active. All cavities are driven by solid-state power amplifiers and the RF fields are regulated by digital low-level RF control systems. The cavity and ancillaries, high-power RF system and low-level RF control system are in the prototyping phase. This paper presents the current status and progress of the RF system for HEPS.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB380  
About • paper received ※ 09 May 2021       paper accepted ※ 09 June 2021       issue date ※ 24 August 2021  
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MOPAB382 Synchrotron Light Shielding for the 166 MHz Superconducting RF Section at High Energy Photon Source cavity, shielding, synchrotron, radiation 1169
 
  • X.Y. Zhang, Z.Q. Li, Q. Ma, P. Zhang
    IHEP, Beijing, People’s Republic of China
 
  Funding: This work was supported by High Energy Photon Source, a major national science and technology infrastructure in China.
The High Energy Photo Source (HEPS) project has been under construction since 2019, and will be first diffraction-limited synchrotron light source in China. A 6 GeV electron beam with 200 mA current will be stored in the main ring. If synchrotron light produced from this energetic electron beam hits the superconducting cavity’s surface, it would cause thermal breakdown of the superconductivity. In the current lattice design, these lights cannot be fully blocked by the collimator in the upstream lattice cell, therefore a shielding scheme inside the rf section is required. This however brings great challenges to the already limited space. The design of the collimator has been focused on fulfilling shielding requirements while optimizing beam impedance, synchrotron light power density, thermal and mechanical stabilities. Shielding materials are subsequently chosen with dedicated cooling to ensure long-term stable operations. In this paper, a shielding scheme inside the rf section of the HEPS storage ring is presented. The synchrotron light mainly from the upstream bending magnet is successfully block. The sensitivity to beam position movement and installation error is also analyzed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB382  
About • paper received ※ 17 May 2021       paper accepted ※ 11 June 2021       issue date ※ 23 August 2021  
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TUXA01 Advances in Understanding of Ion Effects in Electron Storage Rings simulation, emittance, ion-effects, injection 1267
 
  • J.R. Calvey, M. Borland, T.K. Clute, J.C. Dooling, L. Emery, J. Gagliano, J.E. Hoyt, P.S. Kallakuri
    ANL, Lemont, Illinois, USA
 
  Ion instability, in which beam motion couples with trapped ions in an accelerator, is a serious concern for high-brightness electron storage rings. For the APS-Upgrade, we plan to mitigate coherent ion instability using a compensated gap scheme. To study incoherent effects (such as emittance growth), an IONEFFECTS element has been incorporated into the particle tracking code ELEGANT. The simulations include multiple ionization, transverse impedance, and charge variation between bunches. Once these effects are included, the simulations show good agreement with measurements at the present APS. We have also installed a gas injection system, which creates a controlled pressure bump of Nitrogen gas in a short section of the APS ring. The resulting ion instability was studied under a wide variety of beam conditions. For cases with no or insufficient train gaps, large emittance growth was observed. IONEFFECTS simulations of the gas injection experiment and APS-U storage ring show the possibility of runaway emittance blowup, where the blown-up beam traps more ions, driving further instability.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUXA01  
About • paper received ※ 24 June 2021       paper accepted ※ 27 July 2021       issue date ※ 10 August 2021  
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TUXA07 Beam Dynamics Study in a Dual Energy Storage Ring for Ion Beam Cooling* cavity, electron, focusing, emittance 1290
 
  • B. Dhital, G.A. Krafft
    ODU, Norfolk, Virginia, USA
  • Y.S. Derbenev, D. Douglas, A. Hutton, G.A. Krafft, F. Lin, V.S. Morozov, Y. Zhang
    JLab, Newport News, Virginia, USA
 
  Funding: * Work supported by the U.S. Department of Energy, Office of Science, and Office of Nuclear Physics under Contracts DE-AC05-06OR23177 and DE-AC02-06CH11357. / Jefferson Lab EIC Fellowship2020.
A dual energy storage ring designed for beam cooling consists of two closed rings with significantly different energies: the cooling and damping rings. These two rings are connected by an energy recovering superconducting RF structure that provides the necessary energy difference. In our design, the RF acceleration has a main linac and harmonic cavities both running at crest that at first accelerates the beam from low energy EL to high energy EH and then decelerates the beam from EH to EL in the next pass. The purpose of the harmonic cavities is to extend the bunch length in a dual energy storage ring as such a longer bunch length may be very useful in a cooling application. Besides these cavities, a bunching cavity running on zero-crossing phase is used outside of the common beamline to provide the necessary longitudinal focusing for the system. In this paper, we present a preliminary lattice design along with the fundamental beam dynamics study in such a dual energy storage ring.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUXA07  
About • paper received ※ 19 May 2021       paper accepted ※ 07 June 2021       issue date ※ 28 August 2021  
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TUPAB044 Preliminary Study of the on-Axis Swap-Out Injection Scheme for the Southern Advanced Photon Source injection, kicker, septum, electron 1447
 
  • Y. Han, X.H. Lu, Y. Zhao
    IHEP CSNS, Guangdong Province, People’s Republic of China
  • L. Huang, Y. Jiao, X. Liu, S. Wang
    IHEP, Beijing, People’s Republic of China
 
  The Southern Advanced Photon Source (SAPS) is a project under design, which aims at constructing a 4th generation storage ring with emittance below 100 pm.rad at the electron beam energy of around 3.5 GeV. The extremely low emittance will result in a very small dynamic aperture for the storage ring which makes it difficult to use the conventional off-axis accumulation injection. In this case, it is probably necessary to consider the transverse on-axis injection or the longitudinal injection. In this paper, the transverse on-axis swap-out injection scheme for the SAPS storage ring is presented. The preliminary parameters of the septum magnets and fast kickers are carefully evaluated.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB044  
About • paper received ※ 17 May 2021       paper accepted ※ 10 June 2021       issue date ※ 27 August 2021  
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TUPAB050 A Long Booster Option for the USSR 6 GeV Storage Ring booster, lattice, injection, optics 1470
 
  • S.M. Liuzzo, N. Carmignani, L.R. Carver, L. Hoummi, T.P. Perron, R. Versteegen, S.M. White
    ESRF, Grenoble, France
  • I.A. Ashanin, S.M. Polozov
    MEPhI, Moscow, Russia
  • I.A. Ashanin, T. Kulevoy, S.M. Polozov
    NRC, Moscow, Russia
  • T. Kulevoy
    ITEP, Moscow, Russia
 
  Funding: European Union’s Horizon 2020 research and innovation program under grant #871072 Russian federation resolution no. 287
The design of the optics of a full length 6 GeV booster for the USSR (Ultimate Source of Synchrotron Radiation) are presented. This option already followed with success by other laboratories, would allow to obtain a small emittance injected beam thus enabling smooth top-up operation. Details of the design inspired by the ESRF DBA lattice and the possible operating modes are described. The transfer lines booster to storage ring are also addressed in this paper.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB050  
About • paper received ※ 12 May 2021       paper accepted ※ 11 June 2021       issue date ※ 24 August 2021  
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TUPAB058 Online Optimizations of Several Observable Parameters at the Advanced Photon Source injection, kicker, photon, sextupole 1492
 
  • Y.P. Sun
    ANL, Lemont, Illinois, USA
 
  Funding: The work is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Online optimizations are known to be powerful tools which may quickly and efficiently improve the particle accelerator key performance parameters in a model-independent way. In this paper, it is presented on the online optimizations of several observable parameters at the Advanced Photon Source storage ring. These observable parameters include the beam lifetime, injection efficiency and topup efficiency, transverse beam sizes, and turn by turn beam position monitors. It is demonstrated that the particle accelerator performance may be greatly enhanced in a relatively short time frame, by optimizing these observable parameters.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB058  
About • paper received ※ 20 May 2021       paper accepted ※ 24 June 2021       issue date ※ 16 August 2021  
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TUPAB059 Measurement of the Advanced Photon Source Lifetime at Different Level of Beta-Beating quadrupole, betatron, optics, simulation 1496
 
  • Y.P. Sun
    ANL, Lemont, Illinois, USA
 
  Funding: The work is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Linear optics correction of a particle accelerator may not be perfect due to the existence of different errors sources in response matrix measurements and optics correction process. Previous numerical simulation study has shown that the single particle beam dynamics performance may be highly correlated with the level of residual beta-beating. In this paper, the machine study results on beam lifetime of the APS storage ring is presented. The experiment is performed at different level of predefined beta-beating with negligible betatron tunes variations. As expected, the measured beam lifetime has an inverse correlation with the level of beta-beating.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB059  
About • paper received ※ 19 May 2021       paper accepted ※ 17 June 2021       issue date ※ 16 August 2021  
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TUPAB060 Machine Learning on Beam Lifetime and Top-Up Efficiency network, operation, emittance, photon 1499
 
  • Y.P. Sun
    ANL, Lemont, Illinois, USA
 
  Funding: The work is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Both unsupervised and supervised machine learning techniques are employed for automatic clustering, modeling and prediction of Advanced Photon Source (APS) storage ring beam lifetime and top-up efficiency archived in operations. The naive Bayes classifier algorithm is developed and combined with k-means clustering to improve accuracy, where the unsupervised clustering of APS beam lifetime and top-up efficiency is consistent with either true label from data archive or Gaussian kernel density estimation. Artificial neural network algorithms have been developed, and employed for training and modelling the arbitrary relations of beam lifetime and top-up efficiency on many observable parameters. The predictions from artificial neural network reasonably agree with the APS operation data.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB060  
About • paper received ※ 22 May 2021       paper accepted ※ 21 June 2021       issue date ※ 22 August 2021  
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TUPAB061 Anomaly Detection by Principal Component Analysis and Autoencoder Approach network, operation, power-supply, photon 1502
 
  • Y.P. Sun
    ANL, Lemont, Illinois, USA
 
  Funding: The work is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Several different approach are employed to identify the abnormal events in some Advanced Photon Source (APS) operation archived dataset, where dimensionality reduction are performed by either principal component analysis or autoencoder artificial neural network. It is observed that the APS stored beam dump event, which is triggered by magnet power supply fault, may be predicted by analyzing the magnets capacitor temperatures dataset. There is reasonable agreement among two principal component analysis based approaches and the autoencoder artificial neural network approach, on predicting future overall system fault which may result in a stored beam dump in the APS storage ring.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB061  
About • paper received ※ 22 May 2021       paper accepted ※ 18 June 2021       issue date ※ 19 August 2021  
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TUPAB065 Solaris Storage Ring Performance After 6 Years of Operation operation, MMI, synchrotron, vacuum 1515
 
  • A.I. Wawrzyniak, A. Curcio, K. Gula, M.A. Knafel, G.W. Kowalski, A.M. Marendziak, R. Panaś, M. Waniczek, M. Wiśniowski
    NSRC SOLARIS, Kraków, Poland
 
  Solaris is a third generation light source operating since 2015 in Kraków, Poland. Between 2015 and 2018 the synchrotron as well as two beamlines were commissioned. During commissioning phases, the good performance of Solaris storage ring has been reached. The beam optics was brought close to the design one. Since October 2018 Solaris storage ring is in the user operation mode. Moreover, two other beamlines with the elliptically polarized undulators used as source were installed and are under commissioning now. In 2020 the total beam availability of 93% was reached with the average circulating current of 400 mA and the total lifetime of 15 h. Over last two years few improvements of the storage ring were done to optimize the storage ring performance. The Landau cavities were tuned to improve the Touschek lifetime and suppress the instabilities. Two diagnostics beamlines were installed and commissioned allowing for the beam sizes in three planes and emittance measurements. The storage ring optics was fine-tuned to increase the dynamic aperture.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB065  
About • paper received ※ 19 May 2021       paper accepted ※ 26 May 2021       issue date ※ 16 August 2021  
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TUPAB107 Accelerator and Light Source Research Program at Duke University FEL, polarization, undulator, electron 1636
 
  • Y.K. Wu
    FEL/Duke University, Durham, North Carolina, USA
 
  Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033.
The accelerator and light source research program at Duke Free-Electron Laser Laboratory (DFELL), TUNL, is focused on the development of the storage ring based free-electron lasers (FELs) and a state-of-the-art Compton gamma-ray source, the High Intensity Gamma-ray Source (HIGS) driven by the storage ring FEL. With a maximum total flux of about 3·1010 gamma/s and a spectral flux of more than 1,000 gamma/s/eV around 10 MeV, the HIGS is the world’s highest-flux Compton gamma-ray source. Operated in the energy range from 1 to 100 MeV, the HIGS is a premier Compton gamma-ray facility in the world for a variety of nuclear physics research programs, both fundamental and applied. In this work, we will describe our recent light source development to enable the production of gamma rays in the higher energy range from 100 and 120 MeV. We will also provide a summary of our recent accelerator physics and FEL physics research activities.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB107  
About • paper received ※ 26 May 2021       paper accepted ※ 14 July 2021       issue date ※ 15 August 2021  
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TUPAB163 Developing a 50 MeV LPA-Based Injector at ATHENA for a Compact Storage Ring plasma, laser, electron, target 1765
 
  • E. Panofski, J. Dirkwinkel, T. Hülsenbusch, A.R. Maier, J. Osterhoff, G. Palmer, T. Parikh, P.A. Walker, P. Winkler
    DESY, Hamburg, Germany
  • C. Braun, T.F.J. Eichner, L. Hübner, S. Jalas, L. Jeppe, M. Kirchen, P. Messner, M. Schnepp, M. Trunk, C.M. Werle
    University of Hamburg, Hamburg, Germany
  • E. Bründermann, B. Härer, A.-S. Müller, C. Widmann
    KIT, Karlsruhe, Germany
  • M. Kaluza, A. Sävert
    HIJ, Jena, Germany
 
  The laser-driven generation of relativistic electron beams in plasma and their acceleration to high energies with GV/m-gradients has been successfully demonstrated. Now, it is time to focus on the application of laser-plasma accelerated (LPA) beams. The "Accelerator Technology HElmholtz iNfrAstructure" (ATHENA) of the Helmholtz Association fosters innovative particle accelerators and high-power laser technology. As part of the ATHENAe pillar several different applications driven by LPAs are to be developed, such as a compact FEL, medical imaging and the first realization of LPA-beam injection into a storage ring. The latter endeavor is conducted in close collaboration between Deutsche Elektronen-Synchrotron (DESY), Karlsruhe Institute of Technology (KIT) and Helmholtz Institute Jena. In the cSTART project at KIT, a compact storage ring optimized for short bunches and suitable to accept LPA-based electron bunches is in preparation. In this conference contribution we will introduce the 50 MeV LPA-based injector and give an overview about the project goals. The key parameters of the plasma injector will be presented. Finally, the current status of the project will be summarized.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB163  
About • paper received ※ 19 May 2021       paper accepted ※ 31 May 2021       issue date ※ 21 August 2021  
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TUPAB213 Important Drift Space Contributions to Non-Linear Beam Dynamics resonance, sextupole, lattice, operation 1914
 
  • J. Frank, M. Arlandoo, P. Goslawski, J. Li, T. Mertens, M. Ries
    HZB, Berlin, Germany
 
  This paper presents an in-depth analysis of the non-linear contributions of drift spaces in beam dynamics for the creation of Transverse Resonance Island Buckets (TRIBs). TRIBs have been successfully generated in BESSY II and MLS at the Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB). They offer the possibility of generating a second stable orbit and, by populating the orbit with a different electron bunch pattern, allow to effectively have two distinct radiation sources in the same machine individually tailored to different user needs. We demonstrate the generation of TRIBs by order of non-linearity on simple lattice configurations by only treating the drift space as the non-linear element. Moreover, we also insert other non-linear magnets to show how they modify the already generated TRIBs from the drift spaces. We conclude by giving a qualitative analysis of the occurring effects, which provides a guideline as to when the linear approximation is insufficient and the non-linear contribution has to be taken into account.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB213  
About • paper received ※ 12 May 2021       paper accepted ※ 31 August 2021       issue date ※ 29 August 2021  
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TUPAB214 Alpha Buckets in Longitudinal Phase Space: A Bifurcation Analysis operation, synchrotron, lattice, closed-orbit 1917
 
  • J. Frank, M. Arlandoo, P. Goslawski, T. Mertens, M. Ries
    HZB, Berlin, Germany
 
  At HZB’s BESSY II and MLS facilities we have the ability to tune the momentum compaction factor α up to second non-linear order. The non-linear dependence α(δ) brings qualitative changes to the longitudinal phase space and introduces new fix points α(δ)=0 which produce the so-called α-buckets. We present with this paper an analysis of this phenomena from the standpoint of bifurcation theory. With this approach we were able to characterize the nature of the fix points and their position in direct dependence on the tunable parameters. Furthermore, we are able to place stringent conditions onto the tunable parameters to either create or destroy α-buckets.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB214  
About • paper received ※ 12 May 2021       paper accepted ※ 17 June 2021       issue date ※ 26 August 2021  
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TUPAB222 Application and Development of the Streak Camera Measurement System at HLS-II experiment, operation, electron, synchrotron 1942
 
  • Y.K. Zhao, S.S. Jin, P. Lu, B.G. Sun, J.G. Wang, F.F. Wu, T.Y. Zhou
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  The dual-axial scan streak camera plays an important role in the super-fast optical measurement and the beam diagnosis of the accelerators. Indeed, the development of the synchrotron light measurement system by virtue of the streak camera provides an effective tool and research platform for accelerator physics and super-fast optical phenomenon. In this paper, the configuration of the streak camera measurement system is roughly described. And the experimental researches are simultaneously performed, including the bunch lengthening, the potential-well distortion, the longitudinal bunch oscillations, and the beam evolution during the single bunch operation mode in the HLS-II storage ring. Moreover, the effects of the RF modulation on the beam lifetime and longitudinal bunch beam dynamics are carried out.  
poster icon Poster TUPAB222 [1.713 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB222  
About • paper received ※ 10 May 2021       paper accepted ※ 16 June 2021       issue date ※ 14 August 2021  
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TUPAB223 Design of Double- and Multi-Bend Achromat Lattices with Large Dynamic Aperture and Approximate Invariants lattice, sextupole, resonance, betatron 1945
 
  • Y. Li, R.S. Rainer, V.V. Smaluk
    BNL, Upton, New York, USA
  • K. Hwang, C.E. Mitchell, R.D. Ryne
    LBNL, Berkeley, California, USA
 
  Funding: Funded by U.S. Department of Energy (DOE) under Contract No. DE-SC0012704 (BNL) and DE-AC02-05CH11231 (LBNL), U.S. DOE Early Career Research Program under the Office of High Energy Physics.
A numerical method to design nonlinear double- and multi-bend achromat (DBA and MBA) lattices with approximate invariants of motion is described. The search for such nonlinear lattices is motivated by Fermilab’s Integrable Optics Test Accelerator (IOTA), whose design is based on an integrable Hamiltonian system with two invariants of motion. While it may not be possible to design an achromatic lattice for a dedicated synchrotron light source storage ring with one or more exact invariants of motion, it is possible to tune the sextupoles and octupoles in existing DBA and MBA lattices to produce approximate invariants. In our procedure, the lattice is tuned while minimizing the turn-by-turn fluctuations of the Courant-Snyder actions Jx and Jy at several distinct amplitudes, while simultaneously minimizing diffusion of the on-energy betatron tunes. The resulting lattices share some important features with integrable ones, such as a large dynamic aperture, trajectories confined to invariant tori, robustness to resonances and errors, and a large amplitude-dependent tune-spread.
 
poster icon Poster TUPAB223 [2.392 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB223  
About • paper received ※ 10 May 2021       paper accepted ※ 15 June 2021       issue date ※ 20 August 2021  
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TUPAB226 Study of the Third-Order Parametric Resonance Induced by RF Modulation simulation, synchrotron, electron, injection 1956
 
  • P.F. Liang, H.S. Xu
    IHEP, Beijing, People’s Republic of China
 
  There were both analytic and experimental studies on the effects of RF modulation on bunch lengthening in electron storage rings. Nevertheless, the increase of bunch energy spread will happen in the meantime. Therefore, the degradation of bunch quality may limit the potential applications of the RF modulation technique. As a consequence, we believe that the comprehensive studies of the parametric resonance induced by RF modulation are necessary for understanding the physics picture better and seeking new possibilities of applications of this technique. The studies on the beam dynamics closed to the 3vs RF phase modulation would be presented here. Based on the basic longitudinal synchrotron equations of motion, we obtained analytically the longitudinal modulated Hamiltonian and various parameters in longitudinal phase space, such as the fixed points, island tune, island width. The validity of the analytic results was checked by simulations. Furthermore, the dependence of the bunch parameters, such as energy spread and bunch length, on the modulation settings is also discussed in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB226  
About • paper received ※ 19 May 2021       paper accepted ※ 21 June 2021       issue date ※ 13 August 2021  
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TUPAB245 WAKEFIELD AND HEAT LOAD STUDY OF THE GATE VALVES AT ILSF STORAGE RING impedance, wakefield, resonance, simulation 2018
 
  • N. Khosravi, E. Ahmadi, M. Akhyani
    ILSF, Tehran, Iran
  • M. Akhyani
    EPFL, Lausanne, Switzerland
  • S. Dastan
    IPM, Tehran, Iran
  • A. Khosravi
    LAPRI, Tehran, Iran
 
  As one part of the ILSF storage ring, the rf-shield of the gate valves generates considerable interest in terms of wake impedance and heat-load. Inside the gate valves, there is a vacuity, which causes low frequencies resonances, and it can lead to beam instabilities. Therefore, controlling and eliminating these frequencies will be substantial. A radio frequency rf-shield structure, which conceals this transverse gap of the gate valves, is indispensable for low emittance chambers. This paper analyzes the wake impedance and thermal behavior of a finger-band RF shield in the gate valve.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB245  
About • paper received ※ 16 May 2021       paper accepted ※ 14 June 2021       issue date ※ 13 August 2021  
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TUPAB255 Longitudinal Beam Dynamics and Coherent Synchrotron Radiation at cSTART synchrotron, radiation, electron, synchrotron-radiation 2050
 
  • M. Schwarz, E. Bründermann, D. El Khechen, B. Härer, A. Malygin, A.-S. Müller, M.J. Nasse, A.I. Papash, R. Ruprecht, J. Schäfer, M. Schuh, P. Wesolowski
    KIT, Karlsruhe, Germany
 
  The compact STorage ring for Accelerator Research and Technology (cSTART) project aims to store electron bunches of LWFA-like beams in a very large momentum acceptance storage ring. The project will be realized at the Karlsruhe Institute of Technology (KIT, Germany). Initially, the Ferninfrarot Linac- Und Test-Experiment (FLUTE), a source of ultra-short bunches, will serve as an injector for cSTART to benchmark and emulate laser-wakefield accelerator-like beams. In a second stage a laser-plasma accelerator will be used as an injector, which is being developed as part of the ATHENA project in collaboration with DESY and Helmholtz Institute Jena (HIJ). With an energy of 50 MeV and damping times of several seconds, the electron beam does not reach equilibrium emittance. Furthermore, the critical frequency of synchrotron radiation is 53 THz and in the same order as the bunch spectrum, which implies that the entire bunch radiates coherently. We perform longitudinal particle tracking simulations to investigate the evolution of the bunch length and spectrum as well as the emitted coherent synchrotron radiation. Finally, different options for the RF system are discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB255  
About • paper received ※ 17 May 2021       paper accepted ※ 21 June 2021       issue date ※ 29 August 2021  
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TUPAB257 Analysis of Multibunch Spectrum for an Uneven Bunch Distribution in a Storage Ring electron, impedance, collider, distributed 2058
 
  • R. Li, F. Marhauser
    JLab, Newport News, Virginia, USA
 
  Funding: This work is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
Modern storage-ring designs often require an uneven bunch distribution pattern. An uneven bunch fill pattern can result in complex structures for the beam current spectra. Particularly at high average beam currents, these complex current spectra need to be taken into account in concern of beam-dynamical effects. In this study, we analyze a beam current spectrum for various filling patterns with bunch trains and gaps. The characteristics of the resulting beam current spectra are illustrated and discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB257  
About • paper received ※ 21 June 2021       paper accepted ※ 28 June 2021       issue date ※ 12 August 2021  
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TUPAB265 Bunch Lengthening of the HALF Storage Ring in the Presence of Passive Harmonic Cavities cavity, simulation, damping, emittance 2082
 
  • T.L. He, Z.H. Bai, G.Y. Feng, W. Li, W.W. Li, G. Liu, L. Wang, H. Xu, S.C. Zhang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  A passive 3rd harmonic RF system, being necessary for the Hefei Advanced Light Facility (HALF) storage ring under design, will be employed to lengthen the bunches for suppressing the intrabeam scattering and improving the beam lifetime. However, the transient beam loading due to the fundamental mode may significantly reduce the bunch lengthening. Since the scale of transient effects is proportional to R/Q, the effects of R/Q on bunch lengthening, in uniform fill pattern with the near-optimum condition fulfilled, are analyzed by multibunches multiparticles tracking simulation. It indicates that the passive superconducting harmonic cavity with a lower R/Q is preferred by HALF.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB265  
About • paper received ※ 16 May 2021       paper accepted ※ 18 June 2021       issue date ※ 20 August 2021  
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TUPAB266 Periodic Transient Beam Loading Effects Predicted by a Semi-Analytical Method cavity, beam-loading, wakefield, simulation 2086
 
  • T.L. He, Z.H. Bai, G. Feng, W. Li, W.W. Li, G. Liu, L. Wang, H. Xu, S.C. Zhang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  In this paper, we improve a semi-analytical method, which can be not only used for bunch lengthening under equilibrium conditions, but also applied to the prediction of a periodic transient beam loading effect. This periodic transient is induced by the presence of the passive harmonic cavity and might be encountered under specific conditions for a ultra-low emittance storage ring with a higher beam current.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB266  
About • paper received ※ 16 May 2021       paper accepted ※ 21 June 2021       issue date ※ 24 August 2021  
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TUPAB279 First Tests of Beam Position Monitor Electronics with Bunch Resolving Capabilities electron, FPGA, electronics, pick-up 2124
 
  • G. Rehm, F. Falkenstern, J. Kuszynski, A. Schälicke
    HZB, Berlin, Germany
 
  We are reporting on first tests of a beam position monitor using 1 GS/s data streams of signals from a four button pickup. The system digitizes signals of ~2 GHz bandwidth using a choice of sampling frequency that realizes equivalent time sampling. The data is subsequently processed in the Fourier domain to unfold the aliased spectral lines and apply an impulse response correction per channel. After transforming back into time domain, individual bunch signals can be clearly identified and selected for further processing and decimation. The paper will provide detail on the hardware implementation and demonstrate the bunch resolving capabilities, long term stability and beam intensity dependence using beam tests in BESSY-II and synthetic signals.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB279  
About • paper received ※ 18 May 2021       paper accepted ※ 06 July 2021       issue date ※ 27 August 2021  
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TUPAB304 Preliminary Investigation of the Noises and Updates on Physics Studies of FOFB in HEPS power-supply, lattice, controls, factory 2197
 
  • X.Y. Huang, Y. Jiao, Y. Wei
    IHEP, Beijing, People’s Republic of China
 
  High Energy Photon Source (HEPS) is a Fourth-generation storage ring light source in China and is under construction. Noises, such as the ambient mechanical vibration and the power supply ripples of magnets, may induce large orbit motions of electron bunches and hence dramatically degrade the emitted photon beam quality. The effect of noises becomes significant and needs to be considered very carefully, especially when the emittances of the electron beam approach the diffraction limit of x-ray. For the HEPS, the noises are modelled and the total beam orbit motion is evaluated considering the spectral characteristics of all the transformation processes from the errors to the orbit. In this paper, we present the preliminary calculation of the effects of noises in HEPS, and the control of the orbit motion with the FOFB system.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB304  
About • paper received ※ 17 May 2021       paper accepted ※ 02 July 2021       issue date ※ 16 August 2021  
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TUPAB358 Novel 500 MHz Solid State Power Amplifier Module Development at Sirius cavity, operation, impedance, synchrotron 2349
 
  • M.H. Wallner, R.H. Farias, A.P.B. Lima, F. Santiago de Oliveira
    LNLS, Campinas, Brazil
 
  A new solid state power amplifier (SSPA) module is being developed at the Brazilian Center for Research in Energy and Materials (CNPEM) to drive one of the superconducting RF cavities to be installed at Sirius, its new 3 GeV fourth generation synchrotron light source. Several prototypes have been built and tested in-house, and a planar balun was designed to achieve a push-pull configuration at deep class AB operation. Efforts to optimize heat exchange in various ways have been made. Results obtained thus far are presented and the next steps concerning development are discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB358  
About • paper received ※ 19 May 2021       paper accepted ※ 18 June 2021       issue date ※ 19 August 2021  
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TUPAB364 Dipole CR FAIR dipole, HOM, simulation, experiment 2367
 
  • K.K. Riabchenko, A.Yu. Pakhomov, T.V. Rybitskaya, A.A. Starostenko, A.S. Tsyganov, K.V. Zhiliaev
    BINP SB RAS, Novosibirsk, Russia
 
  The design of CR dipole magnets (24+2 pieces) for the FAIR project in Germany began in 2014 at BINP. CR is a special storage ring where the main emphasis is placed on efficient stochastic pre-cooling of intense beams of stable ions, rare isotopes, or antiprotons. This type of magnet is an iron-based electromagnet with a straight pole, sector form is realized by cutting ends. The maximum field value is 1.6 T. The integrated over the length of the magnet field quality as a function of radius is dBl/Bl = ± 10-4 with 190 mm good field region as required from the beam dynamics simulations. This challenging field quality is necessary mainly for precise experiments with ion beam in the ISO regime. Below 1.6 T the value dBl/Bl can be higher with a linear approximation up to ± 2.5× 10-4 at the field level of 0.8 T. The first prototype has been manufactured at the end of 2020. Here we describe features of the dipole, 3D calculations, and measurements of the magnetic field.  
poster icon Poster TUPAB364 [1.587 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB364  
About • paper received ※ 09 May 2021       paper accepted ※ 31 May 2021       issue date ※ 28 August 2021  
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TUPAB368 Design of the Longitudinal Gradient Dipole Magnets for HALF dipole, permanent-magnet, lattice, emittance 2378
 
  • M.Y. Mingyao
    Wang, Hefei, People’s Republic of China
  • G.Y. Feng, Z.L. Ren, H. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  Hefei Advanced Light Facility (HALF) is the fourth generation diffraction-limited storage ring light source project in China. The lattice of the storage ring consists of six different dipoles with longitudinal gradients. The longitudinal-gradient dipoles (LGBs) are permanent magnets. This paper presents the designed construction of LGBs and the magnetic field results using OPERA3D. By optimizing the shape of the polar surface, the magnetic field uniformity is optimized to about 5×10-4. With some movable adjusting block, the magnetic field can be controlled accurately. The temperature stability of the magnet is better than 0.0074 T*mm/°C by setting temperature compensating shunt.  
poster icon Poster TUPAB368 [0.862 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB368  
About • paper received ※ 15 May 2021       paper accepted ※ 02 June 2021       issue date ※ 10 August 2021  
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TUPAB370 Development of Long Coil Dynamic Magnetic Field Measurement System for Dipole Magnets of HEPS Booster dipole, booster, interface, injection 2384
 
  • Y.Q. Liu, C.D. Deng, W. Kang, L. Li, S. Li, X. Wu, Y.W. Wu, J.X. Zhou
    IHEP, Beijing, People’s Republic of China
  • C.D. Deng, Y.W. Wu
    DNSC, Dongguan, People’s Republic of China
 
  A magnetic field measurement system for dipole magnets of High Energy Photon Source Booster is designed and developed. The system uses the long coil upflow method to measure the dynamic integral field of the magnet, and the long coil transverse-translation method to measure the integral field distribution error of the magnet. In this paper, the design and implementation of the magnetic measuring system are introduced in detail, and the magnetic field measurement results of the prototype magnet are shown. The measurement results show that the repeatability of the dynamic integral field measurement system is about 2 in 10,000, and the repeatability of the uniform distribution of the integral field is better than 1 in 10,000, which meets the test requirements of the discrete integral field of bulk magnets ±1 parts per thousand and the uniformity of the integral field ±5×10-4@6GeV and ±1×10-3 @0.5GeV.  
poster icon Poster TUPAB370 [1.475 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB370  
About • paper received ※ 16 May 2021       paper accepted ※ 16 June 2021       issue date ※ 17 August 2021  
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TUPAB401 Mechanical Design, Fabrication and Characterization of Electron Beam Position Monitors for Sirius pick-up, operation, vacuum, impedance 2461
 
  • R. Defavari, O.R. Bagnato, M.W.A. Feitosa, F.R. Francisco, G.R. Gomes, D.Y. Kakizaki, R.L. Parise, R.D. Ribeiro
    LNLS, Campinas, Brazil
 
  Beam Position Monitors were designed and manufactured to meet Sirius operation requirements. Final dimensional accuracy and stability of the BPM were achieved by careful specification of its components’ manufacturing tolerances and materials. AISI-305 Stainless Steel was used for the BPM support fabrication due to magnetic and thermal expansion constraints. High purity molybdenum for the electrode pin and Ti6Al4V F136 G23 alloy for housing was used to manufacture the sensor components for their thermal characteristics. The electrical insulator was made of high alumina. The materials were joined by an active metal brazing process using 0,01mm accurate fixtures. The brazed sensors were subjected to dimensional, mechanical, and metallurgical testing, as well as leak detection and optical microscopy inspection at each stage. The sensors were joined in Ti6Al4V F136 BPM bodies using TIG welding. Dimensional sorting was used to choose groups of sensors-to-body, and body-to-support pairs during the final assembly. 160 BPMs are currently in operation on Sirius storage ring. In this contribution, we present the results of BPM manufacturing and testing processes developed for Sirius.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB401  
About • paper received ※ 18 May 2021       paper accepted ※ 31 May 2021       issue date ※ 29 August 2021  
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WEXC04 Simulations of Beam Strikes on Advanced Photon Source Upgrade Collimators using FLASH, MARS, and elegant simulation, electron, photon, radiation 2562
 
  • J.C. Dooling, M. Borland, A.M. Grannan, C.J. Graziani, R.R. Lindberg, G. Navrotski
    ANL, Lemont, Illinois, USA
  • N.M. Cook
    RadiaSoft LLC, Boulder, Colorado, USA
  • D.W. Lee, Y. Lee
    UCSC, Santa Cruz, California, USA
 
  Funding: Work supported by the U.S. D.O.E.,Office of Science, Office of Basic Energy Sciences, under contract number DE-AC02- 06CH11357.
Modeling of high-energy-density electron beams on collimators proposed for the Advanced Photon Source Upgrade (APS-U) storage ring (SR) is carried out with codes FLASH, MARS, and elegant. Code results are compared with experimental data from two separate beam dump studies conducted in the present APS SR. Whole beam dumps of the 6-GeV, 200 mA, ultra-low emittance beam will deposit acute doses of 30 MGy within 10 to 20 microseconds, leading to hydrodynamic behavior in the collimator material. Goals for coupling the codes include accurate modeling of the hydrodynamic behavior, methods to mitigate damage, and understanding the effects of the resulting shower downstream of the collimator. Relevant experiments, though valuable, are difficult and expensive to conduct. The coupled codes will provide a method to model differing geometries, materials, and loss scenarios. Efforts thus far have been directed toward using FLASH to reproduce observed damage seen in aluminum test pieces subjected to varying beam strike currents. Stabilizing the Eulerian mesh against large energy density gradients as well as establishing release criteria from solid to fluid forms are discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEXC04  
About • paper received ※ 19 May 2021       paper accepted ※ 23 July 2021       issue date ※ 30 August 2021  
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WEPAB005 Design Status Update of the Electron-Ion Collider electron, hadron, collider, interaction-region 2585
 
  • C. Montag, E.C. Aschenauer, G. Bassi, J. Beebe-Wang, J.S. Berg, M. Blaskiewicz, A. Blednykh, J.M. Brennan, S.J. Brooks, K.A. Brown, Z.A. Conway, K.A. Drees, A.V. Fedotov, W. Fischer, C. Folz, D.M. Gassner, X. Gu, R.C. Gupta, Y. Hao, A. Hershcovitch, C. Hetzel, D. Holmes, H. Huang, W.A. Jackson, J. Kewisch, Y. Li, C. Liu, H. Lovelace III, Y. Luo, M. Mapes, D. Marx, G.T. McIntyre, F. Méot, M.G. Minty, S.K. Nayak, R.B. Palmer, B. Parker, S. Peggs, B. Podobedov, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, S. Seletskiy, V.V. Smaluk, K.S. Smith, S. Tepikian, R. Than, P. Thieberger, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, S. Verdú-Andrés, E. Wang, D. Weiss, F.J. Willeke, H. Witte, Q. Wu, W. Xu, A. Zaltsman, W. Zhang
    BNL, Upton, New York, USA
  • S.V. Benson, J.M. Grames, F. Lin, T.J. Michalski, V.S. Morozov, E.A. Nissen, J.P. Preble, R.A. Rimmer, T. Satogata, A. Seryi, M. Wiseman, W. Wittmer, Y. Zhang
    JLab, Newport News, Virginia, USA
  • Y. Cai, Y.M. Nosochkov, G. Stupakov, M.K. Sullivan
    SLAC, Menlo Park, California, USA
  • K.E. Deitrick, C.M. Gulliford, G.H. Hoffstaetter, J.E. Unger
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • E. Gianfelice-Wendt
    Fermilab, Batavia, Illinois, USA
  • T. Satogata
    ODU, Norfolk, Virginia, USA
  • D. Xu
    FRIB, East Lansing, Michigan, USA
 
  Funding: Work supported by BSA, LLC under Contract No. DE-SC0012704, by JSA, LLC under Contract No. DE-AC05-06OR23177, and by SLAC under Contract No. DE-AC02-76SF00515 with the U.S. Department of Energy.
The design of the electron-ion collider EIC to be constructed at Brookhaven National Laboratory has been continuously evolving towards a realistic and robust design that meets all the requirements set forth by the nuclear physics community in the White Paper. Over the past year activities have been focused on maturing the design, and on developing alternatives to mitigate risk. These include improvements of the interaction region design as well as modifications of the hadron ring vacuum system to accommodate the high average and peak beam currents. Beam dynamics studies have been performed to determine and optimize the dynamic aperture in the two collider rings and the beam-beam performance. We will present the EIC design with a focus on recent developments.
 
poster icon Poster WEPAB005 [2.095 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB005  
About • paper received ※ 14 May 2021       paper accepted ※ 22 June 2021       issue date ※ 16 August 2021  
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WEPAB079 Optics Studies on the Operation of a New Wiggler and Bunch Shortening at the DELTA Storage Ring wiggler, optics, cavity, operation 2772
 
  • B. Büsing, P. Hartmann, A. Held, S. Khan, C. Mai, D. Schirmer, G. Schmidt
    DELTA, Dortmund, Germany
 
  Funding: Work supported by Deutsche Forschungsgemeinschaft via project INST 212/330-1 AOBJ: 619186
The 1.5-GeV electron storage ring DELTA is a synchrotron light source operated by the TU Dortmund University. Radiation from hard X-rays to the THz regime is provided by dipole magnets and insertion devices like undulators and wigglers. To provide even shorter wavelengths, a new 22-pole superconducting 7-T wiggler has been installed. The edge focusing of the wiggler has a large impact on the linear optics of the storage ring. Measurements regarding its influence and simulations were performed. In addition, a second radiofrequency (RF) cavity has been installed to compensate the increased energy loss per turn due to the new wiggler. As a consequence of the higher RF power, the electron bunches are shorter compared to the old setup with only one cavity. In view of reducing the bunch length even more, studies of the storage ring optics with reduced momentum compaction factor were performed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB079  
About • paper received ※ 19 May 2021       paper accepted ※ 24 June 2021       issue date ※ 01 September 2021  
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WEPAB081 The Broad-Band Impedance Budget in the Storage Ring of the ALS-U Project impedance, vacuum, cavity, wakefield 2779
 
  • D. Wang, K.L.F. Bane, R. Bereguer, T. Cui, S. De Santis, P. Gach, D. Li, T.H. Luo, T. Miller, T. Oliver, O. Omolayo, C. Steier, T.L. Swain, M. Venturini, G. Wang
    LBNL, Berkeley, California, USA
 
  Design work is underway for the upgrade of the Advanced Light Source (ALS-U) to a diffraction-limited soft x-rays radiation source. Like other 4th-generation light source machines, the ALS-U multiple-bend achromat storage-ring (SR) is potentially sensitive to beam-coupling impedance effects. This paper presents the SR broad-band impedance budget in both the longitudinal and transverse planes. In our modeling we follow the commonly accepted approach of separating the resistive-wall and the geometric parts of the impedance, the former being described by analytical formulas and the latter obtained by numerical electromagnetic codes (primarily CST Studio software) assuming perfectly conducting materials. We discuss the main sources of impedance. Results of our analysis are the basis for the single bunch instability study and would feedback on the design of critical vacuum components.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB081  
About • paper received ※ 20 May 2021       paper accepted ※ 01 July 2021       issue date ※ 20 August 2021  
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WEPAB082 Single Bunch Instability Simulations in the Storage Ring of the ALS-U Project impedance, simulation, cavity, operation 2783
 
  • D. Wang, K.L.F. Bane, S. De Santis, M.P. Ehrlichman, D. Li, T.H. Luo, O. Omolayo, G. Penn, C. Steier, M. Venturini
    LBNL, Berkeley, California, USA
 
  As the broad-band impedance modeling and the vacuum chamber design of the new Advanced Light Source storage ring (ALS- U) reach maturity, we report on progress in single-bunch collective effects studies. A pseudo-Green function wake representing the entire ring was earlier obtained by numerical and analytical methods. Macroparticle simulations using the computer code "elegant" and this wake function are used to determine the instability thresholds for longitudinal and transverse motion. We consider various operating conditions, such as without/with higher-harmonic RF cavities, zero/finite linear chromaticity, and without/with a transverse bunch-by-bunch feedback system. Results show enough margin for the broadband impedance budget when the single-bunch instability thresholds are compared with the design bunch charge.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB082  
About • paper received ※ 20 May 2021       paper accepted ※ 01 July 2021       issue date ※ 12 August 2021  
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WEPAB083 Effect of Negative Momentum Compaction Operation on the Current-Dependent Bunch Length operation, simulation, bunching, synchrotron 2786
 
  • P. Schreiber, T. Boltz, M. Brosi, B. Härer, A. Mochihashi, A.-S. Müller, A.I. Papash, R. Ruprecht, M. Schuh
    KIT, Karlsruhe, Germany
 
  Funding: Funded by the European Union’s Horizon 2020 Research and Innovation programme, Grant Agreement No 730871. P.S, T.B are supported by DFG-funded Karlsruhe School of Elementary and Astroparticle Physics.
New operation modes are often considered during the development of new synchrotron light sources. An understanding of the effects involved is inevitable for a successful operation of these schemes. At the KIT storage ring KARA (Karlsruhe Research Accelerator), new modes can be implemented and tested at various energies, employing a variety of performant beam diagnostics devices. Negative momentum compaction optics at various energies have been established. Also, the influence of a negative momentum compaction factor on different effects has been investigated. This contribution comprises a short report on the status of the implementation of a negative momentum compaction optics at KARA. Additionally, first measurements of the changes to the current-dependent bunch length will be presented.
 
poster icon Poster WEPAB083 [1.129 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB083  
About • paper received ※ 19 May 2021       paper accepted ※ 01 July 2021       issue date ※ 26 August 2021  
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WEPAB090 Higher Order Mode Damping for 166 MHz and 500 MHz Superconducting RF Cavities at High Energy Photon Source cavity, HOM, impedance, damping 2798
 
  • H.J. Zheng, Z.Q. Li, F. Meng, N. Wang, H.S. Xu, P. Zhang, X.Y. Zhang
    IHEP, Beijing, People’s Republic of China
 
  Funding: This work was supported in part by High Energy Photon Source, in part by the National Natural Science Foundation of China under Grant No. 11905232.
Superconducting rf cavities have been chosen for High Energy Photon Source, a 6 GeV diffraction-limited synchrotron light source under construction in Beijing. The main accelerating cavity adopted a quarter-wave β=1 structure operating at 166 MHz while the third harmonic cavity utilized the single-cell elliptical geometry at 500 MHz for the storage ring. The high beam current (200 mA) requires a strong damping of higher order modes (HOMs) excited in the superconducting cavities. To meet the beam stability requirements, enlarged beam pipes with a diameter of 505 mm for the 166 MHz cavity and 300 mm for the 500 MHz cavity were chosen to allow all HOMs to propagate along the beam tubes and to be damped by beam-line absorbers. This paper presents the HOM damping scheme and the cavity impedance analysis results. In addition, power losses due to HOMs were also evaluated for various operation modes (high charge and high luminosity) of the HEPS.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB090  
About • paper received ※ 17 May 2021       paper accepted ※ 22 June 2021       issue date ※ 20 August 2021  
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WEPAB119 Beam Injection with a Pulsed Nonlinear Magnet Into the HALF Storage Ring injection, lattice, dynamic-aperture, multipole 2878
 
  • G. Liu, W. Li, L. Wang, P.N. Wang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  The nonlinear optics of the HALF storage ring are well optimized to make it possible to inject the beam with the pulsed multipole injection scheme. In this paper, the injection scheme is studied with an innovatively designed pulsed nonlinear magnet. The layout and parameters of the injection system are well designed based on the acceptance analysis. The injection process is simulated with particle tracking is presented in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB119  
About • paper received ※ 20 May 2021       paper accepted ※ 29 July 2021       issue date ※ 13 August 2021  
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WEPAB120 Upgrades to the Booster to Storage Ring Transfer Line at the Canadian Light Source booster, septum, injection, extraction 2881
 
  • W.A. Wurtz, T. Batten, B.E. Bewer, M. Bree, S.R. Carriere, A.M. Duffy, B. Fogal, L.X. Lin, C.M. Randall, B.A. Schneider, J.M. Vogt, J. Willard, T. Wilson
    CLS, Saskatoon, Saskatchewan, Canada
  • P. Kuske
    HZB, Berlin, Germany
 
  Investigations into the booster to storage ring transfer process identified non-linear fields in the booster extraction septum as the cause for the poor transfer efficiency. We found that by correcting the trajectory through the septum, the transfer efficiency improved substantially. This motivated an upgrade project to reliably control the trajectory through the septum and transfer line, to provide improved diagnostics and to implement a set of four horizontal scrapers to reduce the horizontal emittance of the beam before it reaches the storage ring.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB120  
About • paper received ※ 10 May 2021       paper accepted ※ 24 June 2021       issue date ※ 23 August 2021  
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WEPAB121 Design and Simulation of Transparent Injection Upgrade for the CLS Storage Ring injection, kicker, sextupole, simulation 2885
 
  • P.J. Hunchak, M.J. Boland
    University of Saskatchewan, Saskatoon, Canada
  • D. Bertwistle, M.J. Boland
    CLS, Saskatoon, Saskatchewan, Canada
 
  The Canadian Light Source (CLS) synchrotron uses four fast kicker magnets to inject electrons into the storage ring from a 2.9 GeV booster ring. The injection occurs over several turns of the stored beam, which is also perturbed by the injection kickers. The resultant oscillations of the stored beam can negatively affect beamline experiments, so it is desirable to implement an injection scheme which does not disturb the stored beam. Injection schemes of this type allow for transparent injection and are beneficial for planned top-up operations of the CLS storage ring. Many alternative injection techniques were examined as they apply to the CLS storage ring. Pulsed multipole magnets and a non-linear kicker (NLK) are the most viable options for integration with the current ring. Non-linear kicker designs are also being considered for the proposed CLS2 and studying the NLK in the limitations of the current machine provides insight to guide the work on the new machine. Simulation with the accelerator code ELEGANT shows the viability of the non-linear kicker design as developed at BESSY, MAX IV and SOLEIL for transparent injection at the CLS.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB121  
About • paper received ※ 19 May 2021       paper accepted ※ 16 July 2021       issue date ※ 01 September 2021  
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WEPAB124 The Three Dipole Kicker Injection Scheme for the ALS-U Accumulator Ring injection, kicker, septum, booster 2896
 
  • M.P. Ehrlichman, T. Hellert, S.C. Leemann, G. Penn, C. Steier, C. Sun, M. Venturini, D. Wang
    LBNL, Berkeley, California, USA
 
  The ALS-U light source will implement on-axis swap-out injection of individual trains employing an accumulator between the booster and storage rings. The accumulator ring design is a twelve period triple-bend achromat that will be installed along the inner circumference of the storage-ring tunnel. A non-conventional injection scheme will be utilized for top-off off-axis injection from the booster into the accumulator ring meant to accommodate a relatively narrow vacuum-chamber aperture while maximizing injection efficiency. The scheme incorporates three dipole kickers distributed over three sectors, with two kickers perturbing the stored beam and the third affecting both the stored and the injected beam trajectories. This paper describes this ‘‘3DK’’ injection scheme, how it was chosen, designed and optimized, and how we evaluated its fitness as a solution for booster-to-accumulator ring injection against alternate injection schemes.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB124  
About • paper received ※ 20 May 2021       paper accepted ※ 01 July 2021       issue date ※ 13 August 2021  
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WEPAB125 Acceptance Analysis Method for the Scheme Design of Multipole Kicker Injection injection, kicker, multipole, simulation 2900
 
  • P.N. Wang, W. Li, G. Liu, L. Wang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  A pulsed multipole kicker has zero magnetic field at the center, consequently, this injection scheme can be transparent to the stored beam and users. In general, multipole kicker injection schemes are derived from the method of phase space analysis. In this paper, a new method of acceptance analysis based on multi-particles tracking is proposed. Using this method, we can quickly obtain multiple kicker injection schemes and easily make adjustments to them. The details of this method are presented and we apply it to the HALF storage ring as an example. A series of tracking simulations are carried out and results are also discussed.  
poster icon Poster WEPAB125 [0.930 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB125  
About • paper received ※ 18 May 2021       paper accepted ※ 09 June 2021       issue date ※ 13 August 2021  
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WEPAB188 New Method to Search for Axion-Like Particles Demonstrated with Polarized Beam at the COSY Storage Ring polarization, resonance, experiment, dipole 3057
 
  • S. Karanth
    Jagiellonian University, Kraków, Poland
 
  The axion was originally proposed to explain the small size of CP violation in quantum chromodynamics. It might be a candidate for dark matter in the universe. Axions or axion-like particles (ALPs) when coupled to gluons induce an oscillating Electric Dipole Moment (EDM) along the nucleon’s spin direction. At the Cooler Synchrotron (COSY) in Jülich, this principle was used to perform a first test experiment to search for ALPs using an in-plane polarized deuteron beam. If the spin precession frequency equals the EDM oscillation frequency, a resonance occurs that accumulates the rotation of the polarization out of the ring plane. Since the axion frequency is unknown, the beam momentum was ramped to search for a vertical polarization jump that would occur when the resonance is crossed. At COSY, four beam bunches with different polarization directions were used to make sure that no resonance was missed because of the unknown relative phase between the polarization precession and the EDM oscillations. We scanned a frequency window of about a 1-kHz width around the spin precession frequency of 121 kHz. This talk will describe the experiment and show preliminary results.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB188  
About • paper received ※ 19 May 2021       paper accepted ※ 01 July 2021       issue date ※ 31 August 2021  
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WEPAB235 TMCI Theory of Flat Chambers Revisited impedance, coupling, vacuum, simulation 3181
 
  • T.F. Günzel
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  By accounting for the transverse impedance’ quadrupolar component according to the work of R.Lindberg *, no TMCI-instability can be observed in case of a pure horizontal resistive wall impedance of flat vacuum chambers. In order to study this effect more closely, TMCI-theory is reviewed and Lindberg’s work is further developed by including the resonator model as impedance type. The theory is applied to the ALBA-impedance model for the calculation of horizontal TMCI-detuning and threshold. Moreover, a couple of example cases are presented including vertical TMCI-detuning and threshold. Results on both planes are compared to simpler descriptions which account for the quadrupolar impedance effect only by tune shift.
* Ryan Lindberg, Fokker-Planck analysis of transverse collective instabilities in electron storage rings, Phy. Rev. Acc. Beams 19, 124402 (2016)
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB235  
About • paper received ※ 19 May 2021       paper accepted ※ 01 July 2021       issue date ※ 19 August 2021  
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WEPAB239 Effect of Chromaticity and Feedback on Transverse Head-Tail Instability feedback, impedance, coupling, damping 3189
 
  • V.V. Smaluk, G. Bassi, A. Blednykh, A. Khan
    BNL, Upton, New York, USA
 
  Funding: This work was supported by the US Department of Energy under contract DE-SC0012704.
The head-tail instability caused by the beam interaction with short-range wakefields is a major limitation for the single-bunch beam intensity in circular accelerators. The combined effect of the transverse feedback systems and chromaticity suppressing the instability is discussed. Theoretical and experimental studies of the head-tail instability and methods of its mitigation are reviewed. Results of experimental studies of the transverse mode coupling carried out at NSLS-II are compared with the theoretical model and numerical simulations.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB239  
About • paper received ※ 19 May 2021       paper accepted ※ 24 June 2021       issue date ※ 12 August 2021  
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WEPAB264 MOGA Optimization of Superconducting Longitudinal Gradient Bend Based on NbTi Wire solenoid, emittance, lattice, radiation 3257
 
  • C. Chen, Z.H. Bai, G.Y. Feng, Z.L. Ren, Zh.X. Tang, L. Wang, H. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  Funding: Work supported by National Key Research and Development Program of China, (2016YFA0402001)
Multi-bend achromat lattices with unit cells have been used in diffraction-limited storage ring designs. The longitudinal gradient bend can reduce the horizontal emittance below the theoretical minimum of a given magnet structure, and generally the horizontal emittance reduces with the peak field grows. Therefore superconducting longitudinal gradient bend (SLGB) can produce higher peak field value and quasi-hyperbolic field profile to minimize emittance at location of radiation and generate better hard X-rays. NbTi conductor, rather than Nb3Sn conductor, is selected to keep the design and manufacture of SLGB magnet as simple as possible. In this paper, how the field profiles of race-track type coil and solenoid coil change with their geometric parameters is studied, and multi-objective genetic algorithm is used to optimize SLGB magnet structure considering Hefei Advanced Light Facility lattice design demand and NbTi critical current.
 
poster icon Poster WEPAB264 [1.476 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB264  
About • paper received ※ 14 May 2021       paper accepted ※ 05 July 2021       issue date ※ 14 August 2021  
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WEPAB288 A New Timing System for PETRA IV timing, controls, FEL, hardware 3329
 
  • H. Lippek, A. Aghababyan, K. Brede, H.T. Duhme, M. Fenner, U. Hurdelbrink, H. Kay, H. Schlarb, T. Wilksen
    DESY, Hamburg, Germany
 
  At DESY an upgrade of the PETRA III synchrotron light source towards a fourth-generation, low emittance machine PETRA IV is currently being actively pursued. The realization of this new machine implies a new design of the timing and synchronization system since requirements on beam quality and controls will significantly change from the existing implementation at PETRA III. As of now the technical design phase of the PETRA IV project is in full swing. For the timing system the design process of the overall system as well as the evaluation of individual components has been started as of last year. Given the success of the at DESY developed MicroTCA.4-based timing system for the European XFEL accelerator it has been chosen to serve as a basis for the PETRA IV timing system developement as well. We present first design ideas of the major timing system hardware component, a MicroTCA.4-based AMC for distributing clocks, triggers and further bunch-synchronous information within the accelerator complex and to user experiments. First steps of an evaluation process for designing the AMC hardware are briefly illustrated.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB288  
About • paper received ※ 19 May 2021       paper accepted ※ 01 July 2021       issue date ※ 10 August 2021  
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WEPAB303 Machine Learning Applied to Automated Tunes Control at the 1.5 GeV Synchrotron Light Source DELTA quadrupole, simulation, controls, operation 3379
 
  • D. Schirmer
    DELTA, Dortmund, Germany
 
  Machine learning (ML) driven algorithms are finding more and more use cases in the domain of accelerator physics. Apart from correlation analysis in large data volumes, low and high level controls, like beam orbit correction, also non-linear feedback systems are possible application fields. This also includes monitoring the storage ring betatron tunes, as an important task for stable machine operation. For this purpose classical, shallow (non-deep), feed-forward neural networks (NNs) were investigated for automated adjusting the storage ring tunes. The NNs were trained with experimental machine data as well as with simulated data based on a lattice model of the DELTA storage ring. With both data sources comparable tune correction accuracies were achieved, both, in real machine operation and for the simulated storage ring model. In contrast to conventional PID methods, the trained NNs were able to approach the desired target tunes in fewer steps. The report summarizes the current status of this machine learning project and points out possible future improvements as well as other possible applications.  
poster icon Poster WEPAB303 [1.575 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB303  
About • paper received ※ 19 May 2021       paper accepted ※ 05 July 2021       issue date ※ 25 August 2021  
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WEPAB304 Multi-Objective Multi-Generation Gaussian Process Optimizer operation, framework, network, simulation 3383
 
  • X. Huang, M. Song, Z. Zhang
    SLAC, Menlo Park, California, USA
 
  Funding: DOE, Office of Science, Office of Basic Energy Sciences, DE-AC02-76SF00515 and FWP 2018-SLAC-100469 Computing Science, Office of Advanced Scientific Computing Research, FWP 2018-SLAC-100469ASCR.
We present a multi-objective evolutionary optimization algorithm that uses Gaussian process (GP) regression-based models to select trial solutions in a multi-generation iterative procedure. In each generation, a surrogate model is constructed for each objective function with the sample data. The models are used to evaluate solutions and to select the ones with a high potential before they are evaluated on the actual system. Since the trial solutions selected by the GP models tend to have better performance than other methods that only rely on random operations, the new algorithm has much higher efficiency in exploring the parameter space. Simulations with multiple test cases show that the new algorithm has a substantially higher convergence speed and stability than NSGA-II, MOPSO, and some other recent preselection-assisted algorithms.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB304  
About • paper received ※ 17 May 2021       paper accepted ※ 12 July 2021       issue date ※ 28 August 2021  
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WEPAB333 Installation and Commissioning of the Sirius Vacuum System vacuum, booster, MMI, target 3455
 
  • R.M. Seraphim, R.O. Ferraz, H.G. Filho, G.R. Gomes, P.H. Lima, R.F. Oliveira, B.M. Ramos, T.M. Rocha, D.R. Silva, M.B. Silva
    LNLS, Campinas, Brazil
 
  The installation of the Sirius accelerators was completed in 2019. The vacuum installation of the booster took place in October 2018. The booster vacuum chambers were baked-out ex-situ and the vacuum pumps, gauges and valves were assembled prior to the installation in the tunnel. The vacuum installation of the storage ring took place from May to August 2019. The vacuum system of the storage ring is based on fully NEG-coated chambers and each sector was baked-out in-situ for NEG activation. The average static pressure in the booster is in the range of low 10-9 mbar. In the storage ring, 95% of the pressures are in 10-11 mbar range and 5% are in 10-10 mbar range. The first beam was stored in the storage ring in December 2019. The vacuum system has been performing well, and an effective beam cleaning effect has been observed for the NEG-coated chambers. At a beam dose of 70 A-h, the storage ring already achieved the design normalized average dynamic pressure of 3x10 12 mbar/mA. A summary of the installation and the commissioning status of the vacuum system will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB333  
About • paper received ※ 20 May 2021       paper accepted ※ 14 June 2021       issue date ※ 22 August 2021  
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WEPAB335 Aluminum Vacuum Chamber for the Sirius DELTA 52 Undulator vacuum, undulator, synchrotron, emittance 3463
 
  • T.M. Rocha, O.R. Bagnato, R.O. Ferraz, H.G. Filho, P.P.S. Freitas, G.R. Gomes, P.H. Lima, R.F. Oliveira, B.M. Ramos, F. Rodrigues, R.M. Seraphim, D.R. Silva, M.B. Silva
    LNLS, Campinas, Brazil
 
  Sirius is a 3 GeV fourth generation synchrotron light source under commissioning by the Brazilian Synchrotron Light Laboratory (LNLS). Delta Undulators with magnet vertical aperture of 13.6 mm, and period of 52.5 mm will be used for the generation of soft X rays to photoemission spectroscopy and X ray absorption experiments. Extruded aluminum vacuum chambers having small vertical aperture of 7.6 mm and horizontal aperture of 13 mm is proposed. This paper details the design and manufacturing processes of a complete chamber. Challenges regarding the TIG welding for aluminum and NEG coating for small aperture chambers will also be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB335  
About • paper received ※ 18 May 2021       paper accepted ※ 19 July 2021       issue date ※ 20 August 2021  
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WEPAB336 Aluminum Vacuum Chamber for the Sirius Commissioning Undulators undulator, vacuum, cathode, MMI 3467
 
  • B.M. Ramos, O.R. Bagnato, R.O. Ferraz, H.G. Filho, P.P.S. Freitas, G.R. Gomes, P.H. Lima, R.F. Oliveira, T.M. Rocha, F. Rodrigues, R.M. Seraphim, D.R. Silva, M.B. Silva
    LNLS, Campinas, Brazil
 
  Sirius is a 3 GeV fourth generation light source under commissioning by the Brazilian Synchrotron Light Laboratory (LNLS). Compact Linear Polarizing Undulators with magnet vertical aperture of 8 mm have been used for the commissioning of some beam lines. Extruded aluminum vacuum chambers having small vertical aperture of 6 mm and horizontal aperture of 40 mm, were built. This paper details the design and manufacturing processes of a complete chamber and its installation procedure at the storage ring. Challenges regarding the precision machining of the 0.5 mm wall thickness, TIG welding for aluminum, NEG coating for small apertures will also be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB336  
About • paper received ※ 18 May 2021       paper accepted ※ 25 August 2021       issue date ※ 20 August 2021  
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WEPAB341 Injection and Extraction Kickers for the Advanced Light Source Upgrade Project (ALS-U) kicker, impedance, extraction, injection 3487
 
  • W.L. Waldron, D.A. Dawson, S. De Santis, T. Oliver, C. Steier
    LBNL, Berkeley, California, USA
 
  Funding: This work was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source upgrade project (ALS-U) at Lawrence Berkeley National Laboratory includes the construction of a new accumulator ring and the replacement of the existing storage ring. Both ferrite-loaded kickers and stripline kickers are used in the ALS-U design for injection, extraction, and decohering the beam before storage ring extraction. In the accumulator ring, the rise and fall time requirements are based on the single bunch revolution time of 608 ns which allows the use of ferrite-loaded kickers. The 10 ns spacing between bunch trains in the storage ring requires stripline kickers to meet the rise and fall time requirements. Both types of kickers are driven by solid-state inductive voltage adders using MOSFETs. Modeling and prototyping efforts have characterized the kicker impedance and beam-induced heating, and explored the effects of beam strike on electrodes.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB341  
About • paper received ※ 20 May 2021       paper accepted ※ 27 July 2021       issue date ※ 24 August 2021  
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WEPAB353 Design and Commissioning of a Multipole Injection Kicker for the SOLEIL Storage Ring injection, kicker, synchrotron, operation 3525
 
  • R. Ollier, P. Alexandre, R. Ben El Fekih, L.S. Nadolski
    SOLEIL, Gif-sur-Yvette, France
 
  In third-generation synchrotron light sources, achieving an orbit distortion below 10% of the stored beam size is very challenging. The standard injection scheme of SOLEIL is made of 2 septa and 4 kicker magnets installed in a 12 m long straight section. Tuning the 4 kickers, to reduce perturbations, revealed to be almost impossible since it requires having 4 identical magnets, electronics, and Ti coated ceramic chambers. To reach the position stability requirement of the stored beam, a single pulsed magnet with no field on the stored beam path can replace the 4 kickers. Such a device, called MIK (Multipole Injection Kicker), was developed by SOLEIL and successfully commissioned in the MAX-IV 3-GeV ring as the key device used in the standard injection scheme for user operation, reducing the beam orbit distortion below 1 micron in peak value in both planes. A copy of the MIK has been installed in a short straight section of the SOLEIL storage ring, in January 2021. We report MIK positioning studies, the constraints of the project, sapphire chamber coating challenges and the first commissioning results. The R&D MIK is a demonstrator for the injection scheme of SOLEIL upgrade as well.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB353  
About • paper received ※ 21 May 2021       paper accepted ※ 23 July 2021       issue date ※ 31 August 2021  
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WEPAB401 Study for Alternative Cavity Wall and Inductive Insert Material proton, impedance, simulation, experiment 3650
 
  • C.E. Taylor, C.-F. Chen, T.W. Hall, E. Henestroza, J.T.M. Lyles, J. Upadhyay
    LANL, Los Alamos, New Mexico, USA
  • S. Biedron, M.A. Fazio, S.I. Salvador, T.J. Schaub
    UNM-ECE, Albuquerque, USA
 
  Funding: Contract No. 89233218CNA000001, supported by the U.S. Department of Energy’s National Nuclear Security Administration (NNSA), for the management and operation of Los Alamos National Laboratory (LANL).
The goal of this work was to develop a solution to the problem of longitudinal beam instability. Beam instability has been a significant problem with storage rings’ performance for many decades. The proton storage ring (PSR) at the Los Alamos Neutron Science Center (LANCE) is no exception. To mitigate the instability, it was found that ferrite inductive inserts can be used to bunch the protons that are diverging due to the electron background. The PSR was the first storage ring to successfully use inductive inserts to mitigate the longitudinal instability with normal production beams. However, years later new machine upgrades facilitate shorter, more intense beams to meet the needs of researchers. The ferrite inserts used to reduce the transverse instabilities induce a microwave instability with the shorter more intense proton beam. This study investigates alternative magnetic materials for inductive inserts in particle beam storage rings, including the necessary engineering for maintaining the ideal temperature during operation.
’ tjschaub@unm.edu
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB401  
About • paper received ※ 29 May 2021       paper accepted ※ 02 July 2021       issue date ※ 15 August 2021  
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WEPAB402 Status and Progress of the High-Power RF System for High Energy Photon Source cavity, booster, photon, GUI 3653
 
  • T.M. Huang, J. Li, H.Y. Lin, Y.L. Luo, Q. Ma, W.M. Pan, P. Zhang, F.C. Zhao
    IHEP, Beijing, People’s Republic of China
 
  Funding: Work was supported in part by High Energy Photon Source, a major national science and technology infrastructure in China, and in part by the National Natural Science Foundation of China(12075263).
High Energy Photon Source is a 6-GeV diffraction-limited synchrotron light source currently under construction in Beijing. Three types of high-power RF systems are used to drive the booster and the storage ring. For the booster ring, a total of 600-kW continuous-wave (CW) RF power is generated by six 500-MHz solid-state power amplifiers (SSA) and fed into six normal-conducting copper cavities. Concerning the storage ring, five CW 260-kW SSAs at 166 MHz and two CW 260-kW SSAs at 500-MHz are used to drive five fundamental and two third-harmonic superconducting cavities respectively. The RF power distributions are realized by 9-3/16" rigid coaxial line for the 166-MHz system and EIA standard WR1800 waveguide for the 500-MHz one. High-power circulators and loads are installed at the outputs of all SSAs to further protect the power transmitters from damages due to reflected power although each amplifier module is equipped with individual isolators. The overall system layout and the progress of the main components are presented in this paper.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB402  
About • paper received ※ 18 May 2021       paper accepted ※ 02 July 2021       issue date ※ 14 August 2021  
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WEPAB411 Ion Coulomb Crystals in Storage Rings for Quantum Information Science operation, controls, laser, rfq 3667
 
  • K.A. Brown, G.J. Mahler, T. Roser, T.V. Shaftan, Z. Zhao
    BNL, Upton, New York, USA
  • A. Aslam, S. Biedron, T.B. Bolin, C. Gonzalez-Zacarias, S.I. Sosa Guitron
    UNM-ECE, Albuquerque, USA
  • R. Chen, T.G. Robertazzi
    Stony Brook University, Stony Brook, New York, USA
  • B. Huang
    SBU, Stony Brook, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We discuss the possible use of crystalline beams in storage rings for applications in quantum information science (QIS). Crystalline beams have been created in ion trap systems and proven to be useful as a computational basis for QIS applications. The same structures can be created in a storage ring, but the ions necessarily have a constant velocity and are rotating in a circular trap. The basic structures that are needed are ultracold crystalline beams, called ion Coulomb crystals (ICC’s). We will describe different applications of ICC’s for QIS, how QIS information is obtained and can be used for quantum computing, and some of the challenges that need to be resolved to realize practical QIS applications in storage rings.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB411  
About • paper received ※ 19 May 2021       paper accepted ※ 20 July 2021       issue date ※ 20 August 2021  
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THXB01 3D Tracking of a Single Electron in IOTA electron, experiment, synchrotron, radiation 3708
 
  • A.L. Romanov, S. Nagaitsev, J.K. Santucci, G. Stancari, A. Valishev
    Fermilab, Batavia, Illinois, USA
  • N. Kuklev, I. Lobach
    University of Chicago, Chicago, Illinois, USA
 
  High-resolution observations of single-particle dynamics have potential as a powerful tool in the diagnostics, tuning and design of storage rings. We are presenting the results of experiments with single electrons that were conducted at Fermilab’s IOTA ring to explore the feasibility of this approach. A set of sensitive, high-resolution digital cameras was used to detect the synchrotron radiation emitted by an electron, and the resulting images were used to reconstruct the time evolution of oscillation amplitudes in all three degrees of freedom. From the evolution of the oscillation amplitudes, we deduce transverse emittances, momentum spread, damping times, beam energy and estimated residual-gas density and composition. To our knowledge, this is the first time that the dynamics of a single particle in a storage ring has been tracked in all three dimensions. We discuss farther development of a single particle diagnostics that may allow reconstruction of its turn-by-turn coordinates over macroscopic periods of time facilitating ultra-precise lattice diagnostics and direct benchmarking of tracking codes.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THXB01  
About • paper received ※ 24 May 2021       paper accepted ※ 29 July 2021       issue date ※ 11 August 2021  
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THXB04 Non-Invasive Dispersion Function Measurement during Light Source Operations operation, lattice, synchrotron, emittance 3720
 
  • B. Podobedov, Y. Hidaka
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
We implemented a completely parasitic measurement of lattice dispersion functions in both horizontal and vertical planes, which is fully compatible with light source user operations. The measurement is performed by applying principal component analysis and adaptive filtering to very small residual orbit noise components introduced by the RF system and detected in the beam orbit data, sampled at 10 kHz. No changes in RF frequency are required. The measurement, performed once a minute, was shown to be robust and immune to changes in the beam current, residual orbit noise amplitude and frequency content as well as other factors. At low current it was shown to provide similar accuracy to the traditional method (which shifts the 500 MHz RF frequency by ±500 Hz). In this paper we will explain our measurement technique and present typical dispersion function stability achieved during NSLS-II operations.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THXB04  
About • paper received ※ 26 June 2021       paper accepted ※ 13 July 2021       issue date ※ 23 August 2021  
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THXB05 Inverse Orbit Response Matrix Measurements: A Possible On-Line Tool for Optics Control in Storage Rings quadrupole, optics, operation, insertion 3724
 
  • Z. Martí, G. Benedetti, U. Iriso, E. Morales
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  We propose a novel technique to measure the linear optics in storage rings based on the acquisition of the inverse orbit response matrix (iORM). The iORM consists in the orbit correctors magnets (OCM) strength changes needed to produce a local orbit variation in each beam position monitor (BPM). This measurement can be implemented by introducing sequentially small changes in the BPM offsets and logging the OCM setting variations when the orbit correction is running. Very high precision and accuracy in the OCM set-points is required which poses a considerable challenge. Since the orbit feedback (FOFB) is kept running, the iORM could potentially be acquired in parallel to users storage ring operation. Since the iORM is very linear and local, optics perturbations could be easily diagnosed online. This paper introduces the iORM measurement concept and presents the progress of these studies at ALBA, where the implementation of this technique is limited by hysteresis effects in the OCM and the FOFB performance.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THXB05  
About • paper received ※ 19 May 2021       paper accepted ※ 29 July 2021       issue date ※ 12 August 2021  
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THXC07 Adaptive Control of Klystron Operation Parameters for Energy Saving at Storage Ring of TPS klystron, operation, controls, cathode 3748
 
  • T.-C. Yu, F.Y. Chang, M.H. Chang, S.W. Chang, L.J. Chen, F.-T. Chung, Y.D. Li, M.-C. Lin, Z.K. Liu, C.H. Lo, Ch. Wang, M.-S. Yeh
    NSRRC, Hsinchu, Taiwan
 
  To satisfy maximum beam current operation in the storage ring of TPS, the operation parameters of both RF transmitters are set to be able to generate its maxi-mum RF power in daily usage. Under such condition, the klystrons can deliver any power below 300kW at constant AC power consumption which is about 520-530 kW. Hence, the AC power usage is independent of the required RF output power. To best utilize the avail-able AC power based on the required RF power, an adaptive control methodology is proposed here to change the operation parameters of the klystron, cath-ode voltage and anode voltage, according to the pre-sent RF power. The corresponding operation parame-ters are applied by the prior tested table which maps the operation parameters with the different saturation RF power. The test results show that the saved energy can be 32% to 11% from 30mA to 450mA for both RF plants as comparing to constant operation parameters of 1047 kW AC power.  
slides icon Slides THXC07 [1.241 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THXC07  
About • paper received ※ 19 May 2021       paper accepted ※ 06 July 2021       issue date ※ 11 August 2021  
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THPAB037 Insertion Devices Impact on Solaris Storage Ring Optics undulator, insertion, insertion-device, power-supply 3827
 
  • G.W. Kowalski, R. Panaś, A.I. Wawrzyniak
    NSRC SOLARIS, Kraków, Poland
 
  Solaris storage ring is currently operating with three insertion devices. The IDs installed are the APPLE II type elliptically polarised undulators (EPU). The UARPES beamline is operating with the long period length EPU of 120 mm (EPU120) which has a significant impact on the linear optics and tune shift. The linear optics compensation of the EPU120 impact is realised by local adjustment of SQFO quadrupole/sextupole focusing gradient and defocusing gradient in the flanking dipoles. Two additional EPUs with period lengths of 58 and 46.6 mm are recently installed for next beamlines PHELIX and DEMETER, respectively and are under commissioning now. To reduce the impact of all undulators movement the additional correction coils are installed and the correction feedforward tables has been determined experimentally. Additionally to keep the tune at the nominal values the tune feedback is planned to be implemented. Within this presentation the effect of all existing insertion devices on the linear optics based on measurements and simulations to be discussed. Moreover the nonlinear effects, especially the impact on dynamic aperture of Solaris storage ring will be investigated.  
poster icon Poster THPAB037 [2.522 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB037  
About • paper received ※ 18 May 2021       paper accepted ※ 14 July 2021       issue date ※ 30 August 2021  
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THPAB064 LUMOS: A Visible Diagnostic Beamline for the Solaris Storage Ring diagnostics, electron, emittance, synchrotron 3901
 
  • R. Panaś, A. Curcio, A.I. Wawrzyniak
    NSRC SOLARIS, Kraków, Poland
 
  LUMOS is a diagnostic beamline which operates in the visible region. It was installed in the Solaris storage ring during summer 2019. The first light was observed at the beginning of December 2019. During 2020 the beamline was commissioned and equipped with a streak camera setup. Currently, LUMOS allows to analyze far-field and near field images of synchrotron light for transverse beam profile measurements. Moreover, using the streak camera setup, it is also possible to investigate the bunch length, the filling pattern and the longitudinal beam profile changes with respect to the different condition (ramping, 3rd harmonic cavities tuning, etc.). During the presentation the optical setup to be presented along with the measurements conducted with it.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB064  
About • paper received ※ 19 May 2021       paper accepted ※ 07 July 2021       issue date ※ 01 September 2021  
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THPAB073 Study of Seven-Bend-Achromat Lattice Option for Half lattice, emittance, octupole, sextupole 3926
 
  • J.H. Xu, Z.H. Bai, Z.L. Ren, J.J. Tan, P.H. Yang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  • Q. Zhang
    INEST, Hefei, People’s Republic of China
 
  A seven-bend-achromat (7BA) storage ring lattice design for Hefei Advanced Light Facility (HALF) with a beam energy of 2.2 GeV and a circumference of 388.8 m is presented. The 7BA lattice is designed with the combined function bends and reverse bends which has a natural emittance of about 67 pm·rad. Two lattice candidates with different tunes have been selected. One lattice has better nonlinear dynamic performance for off-axis injection. The other lattice provides lower beta functions at the center of straight sections. The results of these studies are discussed in this paper.  
poster icon Poster THPAB073 [1.146 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB073  
About • paper received ※ 15 May 2021       paper accepted ※ 28 July 2021       issue date ※ 16 August 2021  
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THPAB074 ESRF-EBS: Implementation, Performance and Restart of User Operation SRF, MMI, operation, emittance 3929
 
  • J.-L. Revol, P. Berkvens, J.-F. Bouteille, N. Carmignani, L.R. Carver, J.M. Chaize, J. Chavanne, F. Ewald, A. Franchi, L. Hardy, J. Jacob, L. Jolly, G. Le Bec, I. Leconte, S.M. Liuzzo, D. Martin, J. Pasquaud, T.P. Perron, Q. Qin, P. Raimondi, B. Roche, K.B. Scheidt, R. Versteegen, S.M. White
    ESRF, Grenoble, France
 
  The European Synchrotron Radiation Facility - Extremely Brilliant Source (ESRF-EBS) is a facility upgrade allowing its scientific users to take advantage of the first high-energy 4th generation light source. In December 2018, after 30 years of operation, the beam stopped for a 12-month shutdown to dismantle the old storage ring and to install the new X-ray source. In December 2019, the first beam was stored and accumulated in the storage ring, allowing the vacuum conditioning and tuning to be started. The beam was delivered to beamlines in March 2020 for their commissioning. On 25 August, the user programme was restarted with beam parameters very close to nominal values. In this report, the milestones and key aspects of the return to user-mode operation are presented and discussed.  
poster icon Poster THPAB074 [2.864 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB074  
About • paper received ※ 19 May 2021       paper accepted ※ 26 July 2021       issue date ※ 01 September 2021  
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THPAB079 Design Study on Beam Size Measurement System Using SR Interferometry for Low Beam Current electron, synchrotron, radiation, synchrotron-radiation 3949
 
  • W. Li, P. Liu, Y.K. Wu, J. Yan
    FEL/Duke University, Durham, North Carolina, USA
 
  Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033.
To enable reliable measurements of the small vertical size of the electron beam in the Duke storage ring, a measurement system is being developed using synchrotron radiation interferometry (SRI). By relating the transverse beam size to the transverse spatial coherence of synchrotron radiation from a dipole magnet according to the Van Cittert-Zernike theorem, the transverse beam size can be inferred by recording and fitting the interference fringe as a function of the characteristic features of the interference filter used. In this paper, we describe the preliminary design of such a measurement system and present design considerations to make it possible to measure the electron beam vertical size for a wide range of electron beam energies and currents. Especially this system will be optimized to measure the electron beam size for low current operation down to 50 to 100~μA. This beam size measurement system will be used as an important beam diagnostic for the intrabeam scattering research at the Duke storage ring.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB079  
About • paper received ※ 27 May 2021       paper accepted ※ 12 July 2021       issue date ※ 28 August 2021  
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THPAB085 Status of Insertion Device Tuning for the APS Upgrade undulator, photon, MMI, permanent-magnet 3966
 
  • R.J. Dejus, Y. Piao, M.F. Qian, J.M. TerHAAR, I. Vasserman, J.Z. Xu
    ANL, Lemont, Illinois, USA
 
  Funding: Work supported by U.S. Department of Energy, Office of Science, under contract number DE AC02-06CH11357.
The Advanced Photon Source Upgrade (APS-U) project is developing a multi-bend achromat (MBA) lattice at 6.0-GeV beam energy to replace the existing APS storage ring lattice operating at 7.0 GeV. One of the key components of the project is to design, fabricate, and install optimized insertion devices (IDs) for 35 beamlines. A plan was developed to standardize on four new undulator period lengths for 44 new undulators and to reuse 23 existing undulators with four more different period lengths. Early in the Upgrade project we anticipated there would be large challenges in meeting the tight fabrication and tuning schedules so that all undulators would be ready for installation in the upgraded storage ring prior to beam commissioning. With recent developments and techniques used in the magnetic measurement laboratory, we have successfully tuned many of the new and reused undulators to demanding magnetic field requirements. We will report on the tools and techniques used and on results to date.
 
poster icon Poster THPAB085 [0.890 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB085  
About • paper received ※ 19 May 2021       paper accepted ※ 21 June 2021       issue date ※ 15 August 2021  
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THPAB090 Progress with the Diamond-II Storage Ring Lattice lattice, emittance, sextupole, injection 3973
 
  • H. Ghasem, I.P.S. Martin, B. Singh
    DLS, Oxfordshire, United Kingdom
 
  Building on the CDR proposal for the Diamond-II storage ring, a number of changes have been implemented to improve the performance of the lattice. Firstly, anti-bend magnets have been utilized to provide additional control over the dispersion function, and an improved symmetrization in the phase advance between the sextupoles was found to be beneficial for the dynamic aperture. Furthermore, the longitudinal variable bends have been tailored to reduce the emittance and have had transverse gradient added to improve the optics control in the mid-straights. In the absence of IDs, the current design provides 161 pm electron beam emittance, reducing to 139 pm once all effects are taken into account. The dynamic aperture is large enough to support an off-axis injection scheme using a nonlinear kicker and has a lifetime greater than 4 h. In this paper, the main parameters and magnet specifications for the Diamond-II lattice are provided. The related linear and non-linear beam dynamics issues are discussed, along with the impact of IDs.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB090  
About • paper received ※ 19 May 2021       paper accepted ※ 17 June 2021       issue date ※ 26 August 2021  
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THPAB097 Towards Arbitrary Pulse Shapes in the Terahertz Domain laser, electron, radiation, controls 3977
 
  • C. Mai, B. Büsing, A. Held, S. Khan, D. Krieg
    DELTA, Dortmund, Germany
 
  Funding: Work supported by the BMBF (05K19PEC).
The TU Dortmund University operates the 1.5-GeV electron storage ring DELTA as a synchrotron light source in user operation and for accererator physics research. At a dedicated beamline, experiments with (sub-)THz radiation are carried out. Here, an interaction of short laser pulses with electron bunches is used to modulate the electron energy which causes the formation of a dip in the longitudinal electron density, giving rise to the coherent emission of radiation between 75 GHz and 6 THz. The standard mode of operation is the generation of broadband radiation. However, more sophisticated energy modulation schemes were implemented using a liquid-crystal phase modulator. Here, a modulation of the spectral phase of the laser is used to control the spectral shape of the THz pulses. The resulting THz spectra have a relative bandwidth of about 2 %. Measurement results from the different THz generation schemes are presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB097  
About • paper received ※ 18 May 2021       paper accepted ※ 12 July 2021       issue date ※ 24 August 2021  
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THPAB175 nuSTORM Accelerator Challenges and Opportunities collider, target, experiment, emittance 4104
 
  • C.T. Rogers, J.-B. Lagrange
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • N. Gall
    CERN, Meyrin, Switzerland
  • J. Pasternak
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • J. Pasternak
    Imperial College of Science and Technology, Department of Physics, London, United Kingdom
 
  The nuSTORM facility uses a stored muon beam to generate a neutrino source. Muons are captured and stored in a storage ring using stochastic injection. The facility will aim to measure neutrino-nucleus scattering cross-sections with uniquely well-characterized neutrino beams; to facilitate the search for sterile neutrino and other Beyond Standard Model processes with exquisite sensitivity, and to provide a muon source that makes an excellent technology test-bed required for the development of muon beams capable of serving as a multi-TeV collider. In this paper, we describe the latest status of the development of nuSTORM, the R&D needs, and the potential for nuSTORM as a Muon Collider test facility.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB175  
About • paper received ※ 19 May 2021       paper accepted ※ 19 July 2021       issue date ※ 31 August 2021  
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THPAB177 Simulation Model Improvements at the Cooler Synchrotron COSY Using the LOCO Algorithm simulation, quadrupole, dipole, polarization 4111
 
  • V. Poncza, A. Lehrach
    FZJ, Jülich, Germany
  • A. Lehrach, V. Poncza
    RWTH, Aachen, Germany
 
  Funding: ERC Advanced Grant (srEDM #694340) of the European Union
The JEDI (Jülich Electric Dipole moment Investigations) collaboration is searching for Electric Dipol Moments (EDMs) of charged particles in storage rings. In a stepwise approach, a first direct deuteron EDM measurement was performed at the Cooler Synchrotron COSY and design studies for a dedicated proton EDM storage ring are underway. In an experiment with a polarized beam in a storage ring, an EDM leads to a vertical polarization buildup. However, the vertical polarization component is also induced by systematic effects such as magnet misalignments. To investigate systematic effects individually and to support data analysis, a realistic simulation model of the storage ring is needed. In this paper, the development of such a model based on the Bmad software library is presented. Furthermore, various systematic effects and their impact on the spin motion in COSY are investigated and quantified by means of beam and spin tracking simulations.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB177  
About • paper received ※ 19 May 2021       paper accepted ※ 27 July 2021       issue date ※ 12 August 2021  
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THPAB197 Enhancing Efficiency of Multi-Objective Neural-Network-Assisted Nonlinear Dynamics Lattice Optimization via 1-D Aperture Objectives & Objective Focusing lattice, focusing, network, simulation 4156
 
  • Y. Hidaka, D.A. Hidas, F. Plassard, T.V. Shaftan, G.M. Wang
    BNL, Upton, New York, USA
 
  Funding: This work is supported by U.S. DOE under Contract No. DE-SC0012704.
Mutli-objective optimizers such as multi-objective genetic algorithm (MOGA) have been quite popular in discovering desirable lattice solutions for accelerators. However, even these successful algorithms can become ineffective as the dimension and range of the search space increase due to exponential growth in the amount of exploration required to find global optima. This difficulty is even more exacerbated by the resource-intensive and time-consuming tendency for the evaluations of nonlinear beam dynamics. Lately the use of surrogate models based on neural network has been drawing attention to alleviate this problem. Following this trend, to further enhance the efficiency of nonlinear lattice optimization for storage rings, we propose to replace typically used objectives with those that are less time-consuming and to focus on a single objective constructed from multiple objectives, which can maximize utilization of the trained models through local optimization and objective gradient extraction. We demonstrate these enhancements using a NSLS-II upgrade lattice candidate as an example.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB197  
About • paper received ※ 20 May 2021       paper accepted ※ 23 June 2021       issue date ※ 10 August 2021  
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THPAB222 Transverse Impedance Coaxial Wire Measurement in an Extended Frequency Range impedance, simulation, HOM, collective-effects 4227
 
  • E.E. Ergenlik, C. Bruni, D. Le Guidec, P. Lepercq
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • A. Gamelin
    SOLEIL, Gif-sur-Yvette, France
 
  The low energy accelerators are tend to have some instabilities especially the beam coupling impedances which comes from the interaction between the beam and accelerator components. As long as the longitudinal impedance are important, transverse impedance determination is crucial for determine the instabilities which will affect the working efficiency of the accelerators. However due to their small amplitudes and measurement setup configuration they are hardly measurable especially in wide frequency ranges. We developed a specific setup for small diameter pieces (28-40mm) for moving and two wire transverse impedance measurements. The dipolar and quadrupolar impedance measurement even with a few Ω level up to 6 GHz for the bellows of ThomX will be presented. Also the comparison with electromagnetic simulations have been performed and can be seen for dipolar impedance measurements.  
poster icon Poster THPAB222 [1.578 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB222  
About • paper received ※ 19 May 2021       paper accepted ※ 27 July 2021       issue date ※ 23 August 2021  
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THPAB232 Study of Nonlinear Properties of ESR via Tune Scans quadrupole, closed-orbit, optics, controls 4250
 
  • G. Franchetti
    GSI, Darmstadt, Germany
 
  The ESR storage ring at GSI is a key accelerator for the FAIR phase zero. This phase requires several highly specialized beam manipulations, which range from beam storage to deceleration of several ion species with the ultimate goal to provide intense highly charge ions to CRYRING. This plan will bring the ESR storage ring into a unique unexplored regime of accelerator operations where nonlinear dynamics, IBS, cooling, and high intensity will all become strongly interdependent. It is, therefore, necessary to acquire the best knowledge of the machine starting from its nonlinear dynamics properties. In this work, we present the development of a strategy to be used in the ESR, in which tune scans are used to explore the nonlinear properties of the accelerator. This approach is discussed with the help of simulations.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB232  
About • paper received ※ 13 May 2021       paper accepted ※ 13 July 2021       issue date ※ 25 August 2021  
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THPAB264 FOFB System Upgrade to ZynqMP FPGA with Fast ORM Measurement FPGA, closed-orbit, hardware, EPICS 4322
 
  • Y.E. Tan, S. Chen, R.B. Hogan, A. Michalczyk
    AS - ANSTO, Clayton, Australia
 
  The FOFB processor has been ported from a Vertex 6 FPGA to a ZynqMP SoC (System on Chip) to provide additional resources to include the enhanced orbit diagnostics (EOD) system that has been designed to inject sinusoidal and pink noise through the feedback loop. The amplitude, duration, phase and frequency of sinusoidal, amplitude and duration of pink noise is user programmable.  
poster icon Poster THPAB264 [1.601 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB264  
About • paper received ※ 04 June 2021       paper accepted ※ 26 July 2021       issue date ※ 15 August 2021  
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THPAB265 New RF BPM Electronics for the 560 Beam Position Monitors of the APS-U Storage Ring electron, electronics, site, instrumentation 4325
 
  • P. Leban, L. Bogataj, M. Cargnelutti, U. Dragonja, P. Paglovec
    I-Tech, Solkan, Slovenia
  • A.R. Brill, J. Carwardine, W.X. Cheng, N. Sereno
    ANL, Lemont, Illinois, USA
 
  Within the upgrade of the APS storage ring to a multi-bend achromat lattice, 560 RF Beam Position Monitors will be required. The projected beam sizes are below 10 microns in both horizontal and vertical planes, putting stringent requirements on the BPM electronics resolution, long-term stability, beam current dependency, and instrument reproducibility. For the APS-U project, the Libera Brilliance+ instrument has been upgraded in technology and capabilities, including the independent multi-bunch turn-by-turn processing and an improved algorithm to further reduce the crossbar-switch artifacts. More than 140 instruments, equipped with 4 BPM electronics each, are being delivered to Argonne National Laboratory, consisting of the largest scale production for Instrumentation Technologies. In this contribution, the extensive test conditions to which the instruments were exposed and their results will be presented, as well as the beam-based long-term drift measurements with different fill patterns.  
poster icon Poster THPAB265 [9.272 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB265  
About • paper received ※ 16 May 2021       paper accepted ※ 22 June 2021       issue date ※ 21 August 2021  
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THPAB276 X-Ray Double Slit Interferometer Progress at CLS synchrotron, simulation, emittance, photon 4349
 
  • N.A. Simonson, Y. Yousefi Sigari
    University of Saskatchewan, Saskatoon, Canada
  • M.J. Boland
    CLS, Saskatoon, Saskatchewan, Canada
 
  The Canadian Light Source (CLS) is a 3rd generation synchrotron that is used to produce extremely bright synchrotron light that can be used for research. The light at the CLS is produced by an electron storage ring that has an emittance of 20 nm. A 4th generation synchrotron (CLS2) is planned which will reduce the emittance to less than 1 nm and thus reduce the transverse beam size significantly, making it very challenging to measure. A double slit interferometer can be used to measure small transverse beam sizes, as first described by Mitsuhashi. An x-ray double slit interferometer will be designed and tested at the current CLS with the goal of using this setup at CLS2.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB276  
About • paper received ※ 20 May 2021       paper accepted ※ 23 July 2021       issue date ※ 01 September 2021  
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THPAB347 Status of Sirius Storage Ring RF System cavity, operation, MMI, controls 4470
 
  • A.P.B. Lima, D. Daminelli, R.H.A. Farias, F.K.G. Hoshino, F.S. Oliveira, R.R.C. Santos, M.H. Wallner
    LNLS, Campinas, Brazil
 
  The design configuration of the Sirius Light Source RF System is based on two superconducting RF cavities and eight 60 kW solid state amplifiers operating at 500 MHz. The current configuration, based on a 7-cell room temperature cavity, was initially planned for commissioning and initial tests of the beamlines. However, it will have to remain in operation longer than planned. Sirius has been operating in decay mode for beamline tests with an initial current of 70 mA. We present an overview of the first-year operation of the RF system and the preparations for the installation of the two superconducting cavities, which is expected to take place in 2023.  
poster icon Poster THPAB347 [1.322 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB347  
About • paper received ※ 16 May 2021       paper accepted ※ 23 July 2021       issue date ※ 26 August 2021  
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