Keyword: photon
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MOXA02 Status of the APS-U Project emittance, lattice, injection, storage-ring 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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MOPAB018 SASE Gain-Curve Measurements with MCP-Based Detectors at the European XFEL FEL, detector, undulator, radiation 96
 
  • E. Syresin, O.I. Brovko, A.Yu. Grebentsov
    JINR, Dubna, Moscow Region, Russia
  • W. Freund, J. Grünert, J. Liu, Th. Maltezopoulos, D. Mamchyk
    EuXFEL, Schenefeld, Germany
  • M.V. Yurkov
    DESY, Hamburg, Germany
  
  Ra­di­a­tion de­tec­tors based on mi­crochan­nel plates (MCP) are used for char­ac­ter­i­za­tion of the Free-Elec­tron Laser (FEL) ra­di­a­tion and mea­sure­ments of the Self-am­pli­fied spon­ta­neous emis­sion (SASE) gain curve at the Eu­ro­pean XFEL. Pho­ton pulse en­er­gies are mea­sured by the MCPs with an anode and by a pho­to­di­ode. There is one MCP-based de­tec­tor unit in­stalled in each of the three pho­ton beam­lines down­stream of the SASE1, SASE2, and SASE3 un­du­la­tors. MCP de­tec­tors op­er­ate in a wide dy­namic range of pulse en­er­gies, from the level of spon­ta­neous emis­sion up to FEL sat­u­ra­tion. Their wave­length op­er­a­tion range over­laps with the whole range of ra­di­a­tion wave­lengths of SASE1 and SASE2 (from 0.05 nm to 0.4 nm), and SASE3 (from 0.4 nm to 5 nm). In this paper we pre­sent re­sults of SASE gain-curve mea­sure­ments by the MCP-based de­tec­tors.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB018  
About • paper received ※ 18 May 2021       paper accepted ※ 17 August 2021       issue date ※ 23 August 2021  
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MOPAB042 Beam Dynamics Investigation for a New Project of Compton Back Scattering Photon Source at NRNU MEPhI linac, electron, scattering, laser 186
 
  • V.S. Dyubkov, I.A. Ashanin, M. Gusarova, Yu.D. Kliuchevskaia, M.V. Lalayan, S.M. Polozov, A.I. Pronikov, V.I. Rashchikov
    MEPhI, Moscow, Russia
  
  Funding: This project is supported by Russian Foundation for Basic Research, Grant no. 19-29-12036.
The ac­tiv­i­ties on phys­i­cal mod­els de­sign of a com­pact mono­chro­matic ra­di­a­tion source in the x-ray range based on in­verse Comp­ton scat­ter­ing are started at NRNU MEPhI. There are com­par­i­son of two schemes of the pho­ton source here: one of them is con­sid­ered to be based on linac with vari­able en­ergy of 20-60 MeV only and the other one is con­sid­ered as ac­cel­er­a­tor com­plex where linac is sup­posed to be used as in­jec­tor to medium size stor­age ring (en­ergy up to 60 MeV). Pre­lim­i­nary re­sults of linac struc­tures and stor­age ring de­sign as well as elec­tron dy­nam­ics sim­u­la­tion are dis­cussed 		 
poster icon Poster MOPAB042 [0.962 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB042  
About • paper received ※ 13 May 2021       paper accepted ※ 20 May 2021       issue date ※ 10 August 2021  
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MOPAB044 Gas Bremsstrahlung Measurements in the Advanced Photon Source Storage Ring radiation, operation, detector, injection 193
 
  • J.C. Dooling, A.R. Brill, J.R. Calvey
    ANL, Lemont, Illinois, 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.
In the Ad­vanced Pho­ton Source Up­grade stor­age ring (SR), small-aper­ture vac­uum cham­bers pro­vide lim­ited con­duc­tance for pump­ing. Non-evap­orable get­ter (NEG) coat­ings will be used in the SR to sup­port the vac­uum. Ion pumps and cold-cath­ode gauges are typ­i­cally lo­cated away from the vac­uum cham­ber trans­port­ing the beam. Mea­sur­ing gas bremsstrahlung (GB) pho­tons in low-con­duc­tance cham­bers pro­vides a method to de­ter­mine the pres­sure at the beam lo­ca­tion. We re­port on GB mea­sure­ments made in the ID-25 beam­line. A Pb:Glass calorime­ter ra­di­a­tor gen­er­ates Cherenkov ra­di­a­tion when high-en­ergy pho­tons cause pair-pro­duc­tion within the glass. A pho­to­mul­ti­plier tube con­verts the light pulses to elec­tri­cal sig­nals. Data was ob­tained dur­ing nor­mal ma­chine op­er­a­tions start­ing in Jan­u­ary 2020. Data col­lec­tion was fa­cil­i­tated using a 4-chan­nel ITech Beam Loss Mon­i­tor FPGA that al­lows for con­trol of thresh­olds and at­ten­u­a­tion set­tings in both count­ing and pulse-height ac­qui­si­tion modes. Count rates and spec­tra were recorded for the three pri­mary fill pat­terns typ­i­cally used dur­ing SR op­er­a­tions as well as dur­ing gas in­jec­tion ex­per­i­ments; re­sults of these mea­sure­ments will be pre­sented. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB044  
About • paper received ※ 22 May 2021       paper accepted ※ 28 May 2021       issue date ※ 25 August 2021  
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MOPAB055 Generation of Coherent Attosecond X-ray Pulses in the Southern Advanced Photon Source laser, electron, storage-ring, emittance 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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MOPAB058 Swap-Out Safety Tracking for the Advanced Photon Source Upgrade dipole, simulation, electron, power-supply 249
 
  • M. Borland, J.S. Downey, M.S. Jaski
    ANL, Lemont, Illinois, USA
  
  Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The Ad­vanced Pho­ton Source up­grade will op­er­ate in swap-out mode, which is sim­i­lar to top-up but in­volves com­plete re­place­ment of in­di­vid­ual de­pleted bunches in a sin­gle shot. As with top-up, safety is a con­cern given that this process will take place with beam­line shut­ters open. We de­scribe the meth­ods used to model swap-out safety, in­clud­ing cre­ation and val­i­da­tion of a full ring lat­tice based on 3D field maps. We also de­scribe a new method of im­ple­ment­ing com­plex, in­ter­sect­ing chan­nels for elec­tron beams and pho­ton beams, as well as a method of eas­ily iden­ti­fy­ing po­ten­tially dan­ger­ous stray par­ti­cles. Nu­mer­ous po­ten­tial er­rors (e.g., mag­net shorts) were mod­eled, giv­ing a re­li­able in­di­ca­tion of per­for­mance of pro­posed stored beam and mag­net in­ter­locks. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB058  
About • paper received ※ 14 May 2021       paper accepted ※ 28 May 2021       issue date ※ 29 August 2021  
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MOPAB073 Beam Loss Simulations During Beam Dumping in Heps kicker, lattice, simulation, dumping 294
 
  • X. Cui, Y. Jiao, Y.L. Zhao
    IHEP, Beijing, People’s Republic of China
  
  The High En­ergy Pho­ton Source (HEPS) is a 6 GeV stor­age ring light source under con­struc­tion in China. Sev­eral col­li­ma­tors in­stalled in the vac­uum cham­ber will be used as beam dump in the stor­age ring op­er­a­tion. Pre­lim­i­nary sim­u­la­tions showed that the tem­per­a­ture rise caused by the beam power de­posited on the col­li­ma­tors will far ex­ceed the melt­ing point of the col­li­ma­tor ma­te­r­ial. In order to cure this prob­lem, spe­cial kick­ers are pro­posed to be in­stalled in the ring to mod­u­late the beam dur­ing beam dump­ing, thereby in­creas­ing the size of the beam hit on the col­li­ma­tors. In this ar­ti­cle, some sim­u­la­tion re­sults of the den­sity of par­ti­cles on the col­li­ma­tors dur­ing beam dump­ing for dif­fer­ent HEPS lat­tice and dif­fer­ent kicker pa­ra­me­ters are shown.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB073  
About • paper received ※ 17 May 2021       paper accepted ※ 07 June 2021       issue date ※ 31 August 2021  
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MOPAB075 Proposal of the Southern Advanced Photon Source and Current Physics Design Study linac, storage-ring, 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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MOPAB084 Acceptance Tests and Installation of the IVU and Front End for the XAIRA Beamline of ALBA undulator, vacuum, experiment, insertion 318
 
  • J. Campmany, J. Marcos, V. Massana
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  
  XAIRA is a new beam­line being built at ALBA syn­chro­tron for macro­mol­e­c­u­lar crys­tal­log­ra­phy (MX) de­voted to the study of small bio crys­tals. It aims at pro­vid­ing a full beam with a size of 3x1 µm2 FWHM (hxv) and flux of >3·1012 ph/s (250 mA in Stor­age Ring) at 1 Å wave­length (12.4 keV) to tackle MX pro­jects for which only tiny (<10 μm) or im­per­fect crys­tals are ob­tained. Be­sides, XAIRA aims at pro­vid­ing pho­tons at low en­er­gies, down to 4 keV, to sup­port MX ex­per­i­ments ex­ploit­ing the anom­alous sig­nal of the met­als nat­u­rally oc­cur­ring in pro­teins (na­tive phas­ing), which is en­hanced in the case of small crys­tals and long wave­lengths. To this end, an in-vac­uum un­du­la­tor has been built by a con­sor­tium be­tween Kyma and Re­search In­stru­ments com­pa­nies. In this paper, we pre­sent the re­sults of the Site Ac­cep­tance Tests made at ALBA using a new bench de­vel­oped to mea­sure closed struc­tures, and also the steps done for its in­stal­la­tion in the ALBA tun­nel.  
poster icon Poster MOPAB084 [1.715 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB084  
About • paper received ※ 11 May 2021       paper accepted ※ 20 May 2021       issue date ※ 25 August 2021  
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MOPAB085 Design and Fabrication of a Short Multipole Wiggler and the Front End for the New ALBA Beamline FAXTOR wiggler, vacuum, insertion, insertion-device 321
 
  • J. Campmany, J. Marcos, V. Massana
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  
  FAX­TOR is a new hard XR to­mog­ra­phy beam line that is being built at ALBA in order to ful­fil the needs that can­not be cur­rently cov­ered by the MIS­TRAL VUV and soft XR beam­line. This beam line needs a small source size as well higher than 1012 Pho­tons per sec­ond through an aper­ture of 4x1 mm2 in the whole range 5 to 60 keV, for a cur­rent of 250 mA in Stor­age Ring with source size main­tained below 310 µm hor­i­zon­tal and 25 µm ver­ti­cal. The con­tract was awarded to AVS-US Com­pany. In this paper we pre­sent the de­sign fi­nally se­lected as well as the pre­lim­i­nary de­sign car­ried out by man­u­fac­turer to im­ple­ment the con­cep­tual model de­signed by ALBA.  
poster icon Poster MOPAB085 [1.879 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB085  
About • paper received ※ 11 May 2021       paper accepted ※ 20 May 2021       issue date ※ 31 August 2021  
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MOPAB086 Design of Front End and a 3-Pole-Wiggler as a Photon Source for BEATS Beamline at SESAME wiggler, vacuum, synchrotron, insertion 324
 
  • J. Campmany, J. Marcos
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  • M. Al Nadjawi, M. Attal, G. Lori
    SESAME, Allan, Jordan
  • I. Cudin
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • S. Guiducci
    INFN/LNF, Frascati, Italy
  • P. Van Vaerenbergh
    ESRF, Grenoble, France
  
  BEATS is an in­ter­na­tional col­lab­o­ra­tion funded by EU in order to de­sign and im­ple­ment an XR to­mog­ra­phy beam line in SESAME Jor­dan­ian syn­chro­tron. ALBA con­tri­bu­tion con­sists in the de­sign of the pho­ton source and the Front End el­e­ments. In this paper we pre­sent the con­cep­tual de­signs of both the 3-pole wig­gler uses as pho­ton source as well as the Front End el­e­ments de­signed for the beam­line.  
poster icon Poster MOPAB086 [2.306 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB086  
About • paper received ※ 11 May 2021       paper accepted ※ 21 May 2021       issue date ※ 17 August 2021  
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MOPAB090 Status of HEPS Insertion Devices Design undulator, radiation, wiggler, insertion 339
 
  • X.Y. Li, Y. Jiao, H.H. Lu, S.K. Tian
    IHEP, Beijing, People’s Republic of China
  
  HEPS is a 4th gen­er­a­tion light source with the en­ergy of 6 GeV and ul­tralow emit­tance of 34 pm.​rad. A total of 14 beam­lines with 19 in­ser­tion de­vices has been planned in the first phase, in­clud­ing 6 cryo­genic un­du­la­tors, 5 in-vac­uum un­du­la­tors, and two spe­cial non-pla­nar IDs. The schemes and pa­ra­me­ters of all the IDs are planned to be de­ter­mined in this year. We re­port on the sta­tus of the de­sign of these IDs and their ef­fects on beam dy­nam­ics.  
poster icon Poster MOPAB090 [0.633 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB090  
About • paper received ※ 13 May 2021       paper accepted ※ 01 July 2021       issue date ※ 10 August 2021  
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MOPAB096 Rocking Curve Imaging Experiment at SSRL 10-2 Beamline wiggler, experiment, radiation, lattice 357
 
  • A. Halavanau, R. Arthur, B. Johnson, J.P. MacArthur, G. Marcus, R.A. Margraf, Z. Qu, T. Rabedeau, T. Sato, C.J. Takacs, D. Zhu
    SLAC, Menlo Park, California, USA
  
  Stan­ford Syn­chro­tron Ra­di­a­tion Light­source (SSRL) serves a wide sci­en­tific com­mu­nity with its va­ri­ety of X-ray ca­pa­bil­i­ties. Re­cently, we have em­ployed a wig­gler source lo­cated at beam­line 10-2 to per­form high res­o­lu­tion rock­ing curve imag­ing (RCI) of di­a­mond and sil­i­con crys­tals. In-house X-ray RCI ca­pa­bil­ity is im­por­tant for the up­com­ing cav­ity-based x-ray source de­vel­op­ment pro­jects at SLAC, such as cav­ity-based XFEL (CBXFEL) and X-ray laser os­cil­la­tor (XLO). In this pro­ceed­ing, we de­scribe the­o­ret­i­cal con­sid­er­a­tions, and pro­vide ex­per­i­men­tal re­sults, val­i­dat­ing the de­sign of our ap­pa­ra­tus. We also pro­vide a plan for fu­ture im­prove­ments of the RCI@​SSRL pro­gram.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB096  
About • paper received ※ 19 May 2021       paper accepted ※ 27 July 2021       issue date ※ 10 August 2021  
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MOPAB097 Two Color Grating design for Soft X-Ray Self-Seeding at LCLS-II FEL, electron, simulation, laser 361
 
  • A. Halavanau, D. Cocco, E. Hemsing, G. Marcus, D.S. Morton
    SLAC, Menlo Park, California, USA
  • G.R. Wilcox
    Cornell University, Ithaca, New York, USA
  
  A new grat­ing de­sign is ex­am­ined for the soft x-ray self-seed­ing sys­tem (SXRSS) at LCLS-II to ul­ti­mately pro­duce sta­ble two-color XFEL pulses. The grat­ing per­for­mance is an­a­lyzed with Fourier op­tics meth­ods. The final XFEL per­for­mance is as­sessed via full nu­mer­i­cal XFEL sim­u­la­tions that sub­stan­ti­ate the fea­si­bil­ity of the pro­posed de­sign.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB097  
About • paper received ※ 19 May 2021       paper accepted ※ 27 July 2021       issue date ※ 21 August 2021  
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MOPAB120 Update on Injector for the New Synchrotron Light Source in Thailand linac, storage-ring, synchrotron, injection 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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MOPAB126 BESSY III & MLS II - Status of the Development of the New Photon Science Facility in Berlin undulator, radiation, lattice, emittance 451
 
  • P. Goslawski, M. Abo-Bakr, F. Andreas, M. Arlandoo, J. Bengtsson, V. Dürr, K. Holldack, J.-G. Hwang, A. Jankowiak, B.C. Kuske, J. Li, A.N. Matveenko, T. Mertens, A. Meseck, E.C.M. Rial, M. Ries, M.K. Sauerborn, A. Schälicke, M. Scheer, P. Schnizer, L. Shi, J. Viefhaus
    HZB, Berlin, Germany
  • J. Lüning
    UPMC, Paris, France
  
  HZB op­er­ates and de­vel­ops two syn­chro­tron ra­di­a­tion sources at Berlin Adler­shof. The larger one, BESSY II with an en­ergy of 1.7 GeV and 240 m cir­cum­fer­ence is op­ti­mized for soft-X rays and in op­er­a­tion since 1999. The smaller one is the MLS (Metrol­ogy Light Source), owned by the Physikalis­che Tech­nis­che Bun­de­sanstalt (PTB) - Ger­many’s Na­tional Metrol­ogy In­sti­tute. It is de­signed to ful­fill the spe­cial metrol­ogy needs of the PTB with an en­ergy of 0.6 GeV and 48 m cir­cum­fer­ence, cov­er­ing the spec­tral range from THz and IR to EUV/VUV. In 2020 a dis­cus­sion process has been started to de­fine the re­quire­ments for suc­ces­sors of BESSY II and MLS and to study the pos­si­bil­i­ties in­te­grate them into a new pho­ton sci­ence fa­cil­ity in Berlin Adler­shof. Here, we give a sta­tus re­port and pre­sent a first en­vis­aged pa­ra­me­ter space to both ma­chines (see also MOPAB262, MOPAB220, MOPAB048, MOPAB242).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB126  
About • paper received ※ 18 May 2021       paper accepted ※ 24 June 2021       issue date ※ 18 August 2021  
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MOPAB131 Synchrotron SOLEIL Upgrade Project lattice, emittance, vacuum, injection 463
 
  • A. Nadji
    SOLEIL, Gif-sur-Yvette, France
  
  To re­main com­pet­i­tive in the fu­ture, SOLEIL is also work­ing on an up­grade pro­ject plan based on Multi-Bend Achro­mat (MBA) lat­tices. The Tech­ni­cal De­sign Re­port of the pro­ject is ex­pected to start in early 2021 im­me­di­ately after the com­ple­tion of the Con­cep­tual De­sign Re­port (CDR) phase. The achieved equi­lib­rium emit­tance in the CDR ref­er­ence lat­tice (80 pm-rad) is about 50 times smaller than that of the ex­ist­ing stor­age ring (4000 pm-rad). By op­er­at­ing on a lin­ear cou­pling res­o­nance, round beam sizes in In­ser­tion De­vices straight sec­tions of less than 10 mi­crons RMS in both planes can be pro­duced. These per­for­mances rely on the use of a 10 mm inner di­am­e­ter cir­cu­lar cop­per vac­uum cham­ber with NEG-coat­ing al­low­ing reach­ing strong quadru­pole gra­di­ents and very strong sex­tu­pole and oc­tu­pole strengths. As all these tech­ni­cal chal­lenges are push­ing the en­gi­neer­ing tech­nol­ogy to the lim­its, they are being in­ves­ti­gated through an in­ten­sive R&D pro­gram based on ex­ten­sive nu­mer­i­cal sim­u­la­tions, pro­to­typ­ing, and mea­sure­ment with the beam. Ex­ten­sive use of the pure per­ma­nent mag­net tech­nol­ogy be­yond what has been done so far in the other sim­i­lar pro­jects is con­sid­ered in this pro­ject.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB131  
About • paper received ※ 22 May 2021       paper accepted ※ 27 July 2021       issue date ※ 30 August 2021  
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MOPAB240 Estimates of Damped Equilibrium Energy Spread and Emittance in a Dual Energy Storage Ring emittance, storage-ring, damping, 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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MOPAB279 Non-Invasive Beam Profile Monitoring for the HL-LHC Hollow Electron Lens electron, proton, background, luminosity 884
 
  • A. Salehilashkajani, N. Kumar, O. Sedláček, C.P. Welsch, H.D. Zhang
    The University of Liverpool, Liverpool, United Kingdom
  • M. Ady, N.S. Chritin, N. Jens, O.R. Jones, R. Kersevan, T. Lefèvre, S. Mazzoni, G. Papazoglou, A. Rossi, G. Schneider, R. Veness
    CERN, Geneva, Switzerland
  • P. Forck, S. Udrea
    GSI, Darmstadt, Germany
  • N. Kumar, O. Sedláček, C.P. Welsch, H.D. Zhang
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  
  Funding: This work was supported by the HL-LHC-UK phase II project funded by STFC under Grant Ref: ST/T001925/1 and the STFC Cockcroft core grant No. ST/G008248/1.
A Hol­low Elec­tron Lens (HEL) is cur­rently under de­vel­op­ment for the High-Lu­mi­nos­ity up­grade of the Large Hadron Col­lider (HL-LHC). In this de­vice, a hol­low elec­tron beam co-prop­a­gates with a cen­tral pro­ton beam and pro­vides ac­tive halo con­trol in the LHC. To en­sure the con­cen­tric­ity of the two beams, a non-in­va­sive di­ag­nos­tic in­stru­ment is cur­rently being com­mis­sioned. This in­stru­ment is a com­pact ver­sion of an ex­ist­ing pro­to­type that lever­ages beam in­duced flu­o­res­cence with su­per­sonic gas cur­tain tech­nol­ogy. This con­tri­bu­tion in­cludes the de­sign fea­tures of this ver­sion of the mon­i­tor, re­cent progress, and fu­ture plans for tests at the Cock­croft In­sti­tute and the elec­tron lens test stand at CERN. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB279  
About • paper received ※ 18 May 2021       paper accepted ※ 15 June 2021       issue date ※ 02 September 2021  
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MOPAB296 Statistical Analysis of 2D Single-Shot PPRE Bunch Measurements radiation, operation, diagnostics, storage-ring 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, detector, storage-ring 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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MOPAB328 Beam Instrumentation for Linear Accelerator of SKIF Synchrotron Light Source electron, diagnostics, radiation, simulation 1016
 
  • X.C. Ma
    BINP, Novosibirsk, Russia
  • M.V. Arsentyeva, E.A. Bekhtenev, V.M. Borin, G.V. Karpov, Yu.I. Maltseva, O.I. Meshkov, D.A. Nikiforov, O.A. Pavlov, V.G. Tcheskidov, V. Volkov
    BINP SB RAS, Novosibirsk, Russia
  • M.V. Arsentyeva, E.A. Bekhtenev, V.M. Borin, Yu.I. Maltseva, O.I. Meshkov, D.A. Nikiforov
    NSU, Novosibirsk, Russia
  • V.M. Borin
    NSTU, Novosibirsk, Russia
  
  A new syn­chro­tron light source SKIF of the 4th gen­er­a­tion is under con­struc­tion at BINP SB RAS (Novosi­birsk, Rus­sia). The lin­ear ac­cel­er­a­tor is SKIF’s in­jec­tor to pro­vide 200 MeV elec­tron beam. The set of di­ag­nos­tics will be ap­plied for tun­ing of the lin­ear ac­cel­er­a­tor and mea­sure­ments of beam pa­ra­me­ters from elec­tron RF gun to out­put of the ac­cel­er­a­tor. It in­cludes 8 flu­o­res­cent screens for the beam trans­verse di­men­sions mea­sure­ment, 2 Cherenkov probes for the beam du­ra­tion mea­sure­ment, mag­netic spec­trom­e­ter with range from 0.6 to 200 MeV, and some beam charge and cur­rent mea­sure­ment de­vices, as Fara­day cup, FCT, BPM along lin­ear ac­cel­er­a­tor. Nu­mer­i­cal sim­u­la­tions of di­ag­nos­tics el­e­ments and re­sults of beam dy­nam­ics sim­u­la­tions are in­tro­duced in paper. Brief de­scrip­tion of the de­sign and pa­ra­me­ters of each di­ag­nos­tics sys­tem is pre­sented. Pos­si­ble sce­nar­ios of lin­ear ac­cel­er­a­tor tun­ing are also dis­cussed.  
poster icon Poster MOPAB328 [2.324 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB328  
About • paper received ※ 19 May 2021       paper accepted ※ 21 May 2021       issue date ※ 31 August 2021  
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MOPAB380 Status and Progress of the RF System for High Energy Photon Source cavity, storage-ring, 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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MOPAB390 Development of a 166.6 MHz Low-Level RF System by Direct Sampling for High Energy Photon Source cavity, LLRF, controls, pick-up 1189
 
  • D.B. Li, H.Y. Lin, Q.Y. Wang, 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.
A dig­i­tal low-level radio fre­quency (LLRF) sys­tem by di­rect sam­pling has been pro­posed for 166.6 MHz su­per­con­duct­ing cav­i­ties at High En­ergy Pho­ton Source (HEPS). The RF field in­side the cav­i­ties has to be con­trolled bet­ter than ±0.1% (peak to peak) in am­pli­tude and ±0.1 deg (peak to peak) in phase. Con­sid­er­ing that the RF fre­quency is 166.6 MHz, which is well within the ana­log band­width of mod­ern high-speed ADCs and DACs, di­rect RF sam­pling and di­rect dig­i­tal mod­u­la­tion can be achieved. A dig­i­tal LLRF sys­tem uti­liz­ing di­rect sam­pling has there­fore been de­vel­oped with em­bed­ded ex­per­i­men­tal physics and in­dus­trial con­trol sys­tem (EPICS) in the field pro­gram­ma­ble gate array (FPGA). The per­for­mance in the lab has been char­ac­ter­ized in a self-closed loop with a resid­ual peak-to-peak noise of ±0.05% in am­pli­tude and ±0.03 deg in phase, which is well below the HEPS spec­i­fi­ca­tions. Fur­ther tests on a warm 166.6 MHz cav­ity in the lab are also pre­sented. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB390  
About • paper received ※ 17 May 2021       paper accepted ※ 09 June 2021       issue date ※ 30 August 2021  
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MOPAB405 Study of Targets to Produce Molybdenum-99 Using 30 MeV Electron Linear Accelerator target, electron, radiation, linac 1222
 
  • T.S. Dixit, A.P. Deshpande, R. Krishnan, A. Shaikh
    SAMEER, Mumbai, India
  
  Funding: Ministry of Electronics and Information Technology, Government of India (MeitY)
Two ap­proaches to pro­duce 99Mo are stud­ied using GEANT4 are re­ported in this paper. First, in con­verter tar­get ap­proach, bremsstrahlung pho­tons are gen­er­ated in a high Z tar­get. The emit­ted pho­tons then hit 100Mo sec­ondary tar­get, pro­duc­ing 99Mo through (gamma, n) re­ac­tion. Sec­ond, in di­rect tar­get ap­proach, high en­ergy elec­tron beam hits 100Mo tar­get, where both (e, gamma) and (gamma, n) re­ac­tions take place si­mul­ta­ne­ously. A 30 MeV, 5-10 kW beam power elec­tron linac is under de­vel­op­ment at SAMEER. The ac­cel­er­a­tion gra­di­ent re­quired to achieve 30 MeV en­ergy will be pro­vided by two linacs op­er­ated in se­ries con­fig­u­ra­tion and the high av­er­age beam power will be achieved by run­ning the sys­tem at high duty op­er­a­tion. Main aim of this study is to op­ti­mize ex­per­i­men­tal pa­ra­me­ters to max­i­mize spe­cific ac­tiv­ity of 99Mo. Since, 100Mo is very ex­pen­sive ma­te­r­ial there­fore ju­di­cious use of the ma­te­r­ial is very im­por­tant. Hence, op­ti­miza­tion of elec­tron beam en­ergy and tar­get di­men­sions are stud­ied in de­tail in both the ap­proaches. It is found that the di­rect tar­get ap­proach gives higher spe­cific ac­tiv­ity com­pared to the con­verter tar­get ap­proach. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB405  
About • paper received ※ 19 May 2021       paper accepted ※ 06 June 2021       issue date ※ 14 August 2021  
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MOPAB409 FLUKA Simulations of 225Ac Production Using Electron Accelerators: Validation Through Comparison with Published Experiments electron, experiment, target, radiation 1226
 
  • T.V. Szabo, I.C. Moraes
    CNPEM, Campinas, SP, Brazil
  • F.A. Bacchim Neto
    LNLS, Campinas, Brazil
  • P.V. Guillaumon
    USP/LAL, Sao Paulo, Brazil
  • H.B. de Oliveira
    IPEN, São Paulo, Brazil
  
  Tar­geted Alpha Ther­apy (TAT) is an ac­tive area of study world­wide. This tech­nique has shown a po­ten­tial in nu­clear med­i­cine to treat metasta­tic dis­ease by alpha par­ti­cles that de­posit en­ergy in small re­gions nearby can­cer cells. Ac-225 is an im­por­tant al­pha-emit­ting that can be used for can­cer TAT. This ra­dioiso­tope shows good po­ten­tial for med­ical ap­pli­ca­tions, there­fore is im­por­tant to study ways of in­crease its pro­duc­tion and avail­abil­ity. One pos­si­ble path for the Ac-225 prod­uct is to ra­di­ate a ra­dium tar­get (Ra-226) on a lin­ear elec­tron ac­cel­er­a­tor (LINAC). Iso­tope pro­duc­tion stud­ies could be im­ple­mented using com­pu­ta­tional tools. In this work, Monte Carlo sim­u­la­tions with FLUKA code were per­formed and com­pared to ex­per­i­men­tal re­sults *. We stud­ied Ac-225 pro­duc­tion by pho­tonu­clear re­ac­tions using a 24 MeV elec­tron beam LINAC hit­ting a tung­sten elec­tron-pho­ton con­verter. Dif­fer­ent en­er­gies and geome­tries were also sim­u­lated to ob­tain op­ti­mal pro­duc­tion con­di­tions. The spe­cific ac­tiv­ity val­ues ob­tained with sim­u­la­tions had a good agree­ment with pub­lished ex­per­i­men­tal re­sults.
* MASLOV, O., et. al. Preparation of 225Ac by 226Ra(g, n) photonuclear reaction on an mt25 microtron. Radiochemistry 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB409  
About • paper received ※ 19 May 2021       paper accepted ※ 09 June 2021       issue date ※ 30 August 2021  
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TUPAB027 Review of Accelerator Limitations and Routes to Ultimate Beams collider, acceleration, electron, luminosity 1397
 
  • F. Zimmermann
    CERN, Geneva, Switzerland
  • R.W. Aßmann
    DESY, Hamburg, Germany
  • M. Bai, G. Franchetti
    GSI, Darmstadt, Germany
  
  Funding: This work was supported in part by the European Commission under the HORIZON 2020 project I.FAST, no. 101004730.
Var­i­ous phys­i­cal and tech­nol­ogy-de­pen­dent lim­its are en­coun­tered for key per­for­mance pa­ra­me­ters of ac­cel­er­a­tors such as high-gra­di­ent ac­cel­er­a­tion, high-field bend­ing, beam size, beam bright­ness, beam in­ten­sity and lu­mi­nos­ity. This paper will re­view these lim­its and the as­so­ci­ated chal­lenges. Pos­si­ble fig­ures-of-merit and path­ways to ul­ti­mate col­lid­ers will also be ex­plored. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB027  
About • paper received ※ 16 May 2021       paper accepted ※ 02 August 2021       issue date ※ 23 August 2021  
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TUPAB046 Preliminary design of the Full Energy Linac Injector for the Southern Advanced Photon Source linac, FEL, gun, injection 1454
 
  • X. Liu
    Institute of High Energy Physics, CAS, Guangdong, People’s Republic of China
  • Y. Jiao, B. Li, S. Wang
    IHEP, Beijing, People’s Republic of China
  
  A 4th gen­er­a­tion mid-en­ergy range dif­frac­tion lim­ited stor­age ring, named as the South­ern Ad­vanced Pho­ton Source (SAPS), is under con­sid­er­a­tion to be built at the same cam­pus as China Spal­la­tion Neu­tron Source (CSNS), pro­vid­ing a charm­ing one-stop so­lu­tion for fun­da­men­tal sci­ences and in­dus­trial ap­pli­ca­tions. While the de­sign of the ring is still under study, a full en­ergy Linac has been pro­posed as one can­di­date op­tion for its in­jec­tor, with the ca­pa­bil­ity of being used as an X-ray Free Elec­tron Laser (XFEL) in the near fu­ture. In this paper, an overview of the pre­lim­i­nary de­sign of the Linac is given and sim­u­la­tion re­sults are dis­cussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB046  
About • paper received ※ 18 May 2021       paper accepted ※ 10 June 2021       issue date ※ 10 August 2021  
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TUPAB052 Current Study of Applying Machine Learning to Accelerator Physics at IHEP network, electron, lattice, target 1477
 
  • J. Wan, Y. Jiao
    IHEP, Beijing, People’s Republic of China
  
  Funding: National Natural Science Foundation of China(No.11922512), Youth Innovation Promotion Association of Chinese Academy of Sciences(No.Y201904) and National Key R&D Program of China(No.2016YFA0401900).
In re­cent years, ma­chine learn­ing (ML) has at­tracted in­creas­ing in­ter­est among the ac­cel­er­a­tor field. As a com­plex col­lec­tion of mul­ti­ple phys­i­cal sub­sys­tems, the de­sign and op­er­a­tion of an ac­cel­er­a­tor can be very non­lin­ear and com­pli­cated, while ML is taken as a pow­er­ful tool to solve such non­lin­ear and com­pli­cated prob­lems. In this study, we re­port on sev­eral suc­cess­ful ap­pli­ca­tions of ML to ac­cel­er­a­tor physics at IHEP. The non­lin­ear dy­nam­ics op­ti­miza­tion of the High En­ergy Pho­ton Source (HEPS) that is a 4th-gen­er­a­tion light source is a chal­leng­ing topic. In this op­ti­miza­tion, we use a ML sur­ro­gate model to fast se­lect the po­ten­tially com­pet­i­tive so­lu­tions for a mul­ti­ob­jec­tive ge­netic al­go­rithm that can sig­nif­i­cantly im­prove the con­ver­gence rate and the di­ver­sity among ob­tained so­lu­tions. Be­sides, we also tried to apply a gen­er­a­tive ad­ver­sar­ial net to solve one-to-many prob­lems of lon­gi­tu­di­nal beam cur­rent pro­file shap­ing. Un­like most su­per­vised ma­chine learn­ing meth­ods than can­not learn one-to-many maps, the gen­er­a­tive ad­ver­sar­ial net-based method is able to pre­dict mul­ti­ple so­lu­tions in­stead of one for a 4-di­pole chi­cane to re­al­ize sev­eral de­sired cus­tom cur­rent pro­files. 		 
poster icon Poster TUPAB052 [0.913 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB052  
About • paper received ※ 11 May 2021       paper accepted ※ 21 June 2021       issue date ※ 27 August 2021  
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TUPAB054 CDR BASELINE LATTICE FOR THE UPGRADE OF SOLEIL lattice, emittance, injection, coupling 1485
 
  • A. Loulergue, D. Amorim, P. Brunelle, A. Gamelin, A. Nadji, L.S. Nadolski, R. Nagaoka, R. Ollier, M.-A. Tordeux
    SOLEIL, Gif-sur-Yvette, France
  
  Pre­vi­ous MBA stud­ies con­verged to­ward a lat­tice com­posed of 20 7BA so­lu­tion elab­o­rated by adopt­ing the sex­tu­pole pair­ing scheme with dis­per­sion bumps orig­i­nally de­vel­oped at the ESRF-EBS. It pro­vided a low nat­ural hor­i­zon­tal emit­tance value of 70-80 pm-rad range at an en­ergy of 2.75 GeV. Due to dif­fi­cul­ties to ac­com­mo­date such lat­tice geom­e­try in the SOLEIL pre­sent tun­nel as well as to pre­serve at best the beam­line po­si­tion­ing, al­ter­na­tive lat­tice based on HOA (Higher-Or­der Achro­mat) type cell has been re­cently in­ves­ti­gated. The HOA type cell being more mod­u­lar and pos­si­bly ex­hibit­ing larger mo­men­tum ac­cep­tance as well as low emit­tances, a so­lu­tion al­ter­nat­ing 7BA and 4BA cells was then iden­ti­fied as the best to adapt the cur­rent beam­line po­si­tion­ing. The SOLEIL CDR up­grade ref­er­ence lat­tice is then com­posed of 20 HOA cells al­ter­nat­ing 7BA and 4BA giv­ing a nat­ural hor­i­zon­tal emit­tance of 80 pm-rad. The lin­ear and non-lin­ear beam dy­namic prop­er­ties of the lat­tice along with the pos­si­bil­ity of hor­i­zon­tal off-axis in­jec­tion at full be­ta­tron cou­pling are pre­sented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB054  
About • paper received ※ 21 May 2021       paper accepted ※ 02 July 2021       issue date ※ 10 August 2021  
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TUPAB058 Online Optimizations of Several Observable Parameters at the Advanced Photon Source injection, storage-ring, kicker, 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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TUPAB060 Machine Learning on Beam Lifetime and Top-Up Efficiency network, operation, storage-ring, emittance 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, storage-ring 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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TUPAB069 The Sabina Terahertz/Infrared Beamline at SPARC-Lab Facility radiation, electron, experiment, laser 1525
 
  • S. Macis
    La Sapienza University of Rome, Rome, Italy
  • M. Bellaveglia, M. Cestelli Guidi, E. Chiadroni, F. Dipace, A. Ghigo, L. Giannessi, A. Giribono, L. Sabbatini, C. Vaccarezza
    INFN/LNF, Frascati, Italy
  • A. Doria, A. Petralia
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • S. Lupi
    Sapienza University of Rome, Roma, Italy
  • V. Petrillo
    INFN-Milano, Milano, Italy
  
  Funding: SABINA is a project co-funded by Regione Lazio within POR-FESR 2014-2020 program.
Fol­low­ing the EU Ter­a­hertz (THz) Road Map*, high-in­ten­sity, ps-long, THz)/In­frared (IR) ra­di­a­tion is going to be­come a fun­da­men­tal spec­troscopy tool for prob­ing and con­trol low-en­ergy quan­tum sys­tems rang­ing from graphene, and Topo­log­i­cal In­su­la­tors, to novel su­per­con­duc­tors** ***. In the frame­work of the SABINA pro­ject, a novel THz/IR beam­line based on an AP­PLE-X un­du­la­tor emis­sion will be de­vel­oped at the SPARC-Lab fa­cil­ity at LNF-INFN. Light will be prop­a­gated from the SPARC-Lab to a new user lab fa­cil­ity nearly 20 m far away. This beam­line will cover a broad spec­tral re­gion from 3 THz to 30 THz, show­ing ps- pulses and en­ergy of tens of µJ with vari­able po­lar­iza­tion from lin­ear to cir­cu­lar. The cor­re­spond­ing elec­tric fields up to 10 MV/cm, are able to in­duce non-lin­ear phe­nom­ena in many quan­tum sys­tems. The beam­line, open to user ex­per­i­ments, will be equipped with a 5 T mag­netic cryo­stat and will be syn­chro­nized with a fs laser for THz/IR pump, VIS/UV probe ex­per­i­ments.
[*] S.S. Dhillon et al., J. Phys. D: Appl. Phys. 50, 043001 (2017);
[**] F. Giorgianni et al., Nature Commun. 7, 11421 (2016);
[***] P. Di Pietro et al., Phys. Rev. Lett. 124, 226403 (2020); 		 
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB069  
About • paper received ※ 16 May 2021       paper accepted ※ 21 June 2021       issue date ※ 25 August 2021  
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TUPAB104 Redesign of the FLASH2 Post-SASE Undulator Beamline undulator, electron, quadrupole, MMI 1626
 
  • F. Christie, J. Rönsch-Schulenburg, S. Schreiber, M. Vogt, J. Zemella
    DESY, Hamburg, Germany
  
  FLASH2 is one of the two SASE (Self-Am­pli­fied Spon­ta­neous Emis­sion) un­du­la­tor beam­lines lines com­pris­ing vari­able gap un­du­la­tors to pro­duce ra­di­a­tion in the XUV and soft X-ray regime at FLASH. Down­stream of the SASE un­du­la­tors the beam­line is cur­rently un­der­go­ing a major re­design. Dur­ing shut­downs in sum­mer 2020 and win­ter 2021 two Po­lariX TDSs (Po­lar­iz­able X-band Trans­verse De­flect­ing Struc­ture) were in­stalled, as well as ad­di­tional di­ag­nos­tics, to mon­i­tor the lon­gi­tu­di­nal phase space den­sity of the elec­tron bunches. Ad­di­tion­ally, an af­ter­burner un­du­la­tor will be in­te­grated in the next shut­down to pro­duce cir­cu­larly po­lar­ized light with wave­lengths down to 1.39 nm. In this paper, we will pre­sent the mod­i­fi­ca­tions that were and will be made to the elec­tron beam­line in the course of this re­design.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB104  
About • paper received ※ 19 May 2021       paper accepted ※ 21 July 2021       issue date ※ 23 August 2021  
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TUPAB114 FEL Performance and Beam Quality Assessment of Undulator Line for the CompactLight Facility. undulator, FEL, brilliance, electron 1655
 
  • H.M. Castañeda Cortés, D.J. Dunning, N. Thompson
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  
  Funding: H2020 CompactLight has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 777431
The H2020 Com­pact­Light Pro­ject aims for the de­sign of in­no­v­a­tive, cost-ef­fec­tive, com­pact FEL fa­cil­i­ties to gen­er­ate higher peak bril­liance ra­di­a­tion in the soft and hard X-ray. In this paper we as­sess via sim­u­la­tion stud­ies the per­for­mance of a vari­ably po­lar­is­ing AP­PLE-X af­ter­burner po­si­tioned down­stream of a he­li­cal Super Con­duct­ing Un­du­la­tor (SCU). We dis­cuss the op­ti­mum bal­ance be­tween the ac­tive SCU length and the af­ter­burner length, con­sid­er­ing the peak bril­liance and pulse en­ergy of the out­put. Our stud­ies are com­ple­mented with analy­sis of the op­ti­cal beam qual­ity of the af­ter­burner out­put to de­ter­mine the de­sign con­straints of the pho­ton beam­line that de­liv­ers the FEL out­put to the ex­per­i­men­tal areas.
* Mak, A., Salen, P., Goryashko, V., Clarke, J., http://uu.diva-portal.org/smash/record.jsf?pid=diva2\%3A1280300&dswid=3236
** Lutman, A. et al. Nature Photonics 10, 468 		 
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB114  
About • paper received ※ 11 May 2021       paper accepted ※ 10 June 2021       issue date ※ 27 August 2021  
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TUPAB141 On the Development of a Low Peak-Power, High Repetition-Rate Laser Plasma Accelerator at IPEN laser, plasma, electron, experiment 1713
 
  • A. Bonatto
    Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
  • E.P. Maldonado
    ITA, São José dos Campos, Brazil
  • R.P. Nunes
    UFRGS, Porto Alegre, Brazil
  • R.E. Samad, F.B.D. Tabacow, N.D. Vieira, A.V.F. Zuffi
    IPEN-CNEN/SP, São Paulo, Brazil
  
  Funding: FAPESP (Grant #2018/25961), CNPq and CAPES.
In this work, the cur­rent sta­tus on the de­vel­op­ment of a laser plasma ac­cel­er­a­tor at the Nu­clear and En­ergy Re­search In­sti­tute (In­sti­tuto de Pesquisas Nu­cleares e Energéticas, IPEN/CNEN), in São Paulo, Brazil, is pre­sented. Short pulses to be pro­duced by an un­der-de­vel­op­ment near-TW, kHz laser sys­tem will be used to ion­ize a gas jet, with a den­sity pro­file de­signed to op­ti­mize the self-in­jec­tion of plasma elec­trons. The same laser pulse will also drive a plasma wake­field, which will allow for elec­tron ac­cel­er­a­tion in the self-mod­u­lated regime. The cur­rent mile­stone is to de­velop the ex­per­i­men­tal setup, in­clud­ing elec­tron beam and plasma di­ag­nos­tics, re­quired to pro­duce elec­tron bunches with en­er­gies of a few MeV. Once this has been achieved, the next mile­stone is to pro­duce beams with en­er­gies higher than 50 MeV. Be­sides kick­start­ing the laser wake­field ac­cel­er­a­tor (LWFA) tech­nol­ogy in Brazil, this pro­ject aims to pave the way for con­duct­ing re­search on the pro­duc­tion of ra­dioiso­topes by pho­tonu­clear re­ac­tions, trig­gered by LWFA-ac­cel­er­ated beams. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB141  
About • paper received ※ 18 May 2021       paper accepted ※ 15 June 2021       issue date ※ 10 August 2021  
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TUPAB246 Numerical Simulation and Beam-Dynamics Study of a Hollow-Core Woodpile Coupler for Dielectric Laser Accelerators GUI, laser, acceleration, electron 2022
 
  • G.S. Mauro, D. Mascali, G. Sorbello, G. Torrisi
    INFN/LNS, Catania, Italy
  • A. Bacci
    INFN/LASA, Segrate (MI), Italy
  • C. De Angelis, A. Locatelli
    University of Brescia, Brescia, Italy
  • A.R. Rossi
    INFN-Milano, Milano, Italy
  • G. Sorbello
    University of Catania, Catania, Italy
  
  Hol­low core di­elec­tric mi­crostruc­tures pow­ered by lasers rep­re­sent a new and promis­ing area of ac­cel­er­a­tor re­search thanks to the higher dam­age thresh­old and ac­cel­er­at­ing gra­di­ents with re­spect to met­als at op­ti­cal wave­lengths. In this paper we pre­sent the de­sign of a di­elec­tric Elec­tro­mag­netic Band Gap (EBG) mode con­verter for high-power cou­pling of the ac­cel­er­at­ing mode in Di­elec­tric Laser Ac­cel­er­a­tors (DLAs). The de­sign is wave­length-in­de­pen­dent, and here we pro­pose an im­ple­men­ta­tion op­er­at­ing at 90.505 GHz (wave­length 3.3 mm) based on a sil­i­con wood­pile struc­ture. The cou­pler is com­posed by two per­pen­dic­u­larly cou­pled hol­low-core wave­guides: a TE-like mode wave­guide (ex­cited from RF/laser power) and a TM-like mode ac­cel­er­at­ing wave­guide. The struc­ture has been nu­mer­i­cally de­signed and op­ti­mized, pre­sent­ing In­ser­tion Losses (IL) < 0.3 dB and an ef­fi­cient mode con­ver­sion in the op­er­at­ing band­width. The prop­er­ties and ef­fec­tive­ness of the con­fined ac­cel­er­at­ing mode have been op­ti­mized in order to de­rive the needed ac­cel­er­at­ing gra­di­ent. The sim­u­lated elec­tric field has been used as input for Astra beam-dy­nam­ics sim­u­la­tions in order to com­pute the beam prop­er­ties.  
poster icon Poster TUPAB246 [2.209 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB246  
About • paper received ※ 18 May 2021       paper accepted ※ 27 July 2021       issue date ※ 13 August 2021  
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TUPAB287 Application of Artificial Neural Network in the APS Linac Bunch Charge Transmission Efficiency linac, operation, kicker, controls 2155
 
  • H. Shang, R. Maulik, Y. Sun
    ANL, Lemont, Illinois, USA
  • T. Xu
    Northern Illinois University, DeKalb, Illinois, USA
  
  Funding: * Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
In re­cent years there has been a rapid growth in ma­chine learn­ing (ML) and ar­ti­fi­cial in­tel­li­gence (AI) ap­pli­ca­tions in ac­cel­er­a­tors. As the scale of com­plex­ity and so­phis­ti­ca­tion of mod­ern ac­cel­er­a­tors grows, the dif­fi­cul­ties in mod­el­ing the ma­chine in­crease greatly in order to in­clude all the in­ter­act­ing sub­sys­tems and to con­sider the lim­i­ta­tion of var­i­ous di­ag­nos­tics to bench­mark against mea­sure­ments. Tools based on ML can help sub­stan­tially in re­veal­ing cor­re­la­tions of ma­chine con­di­tion and beam pa­ra­me­ters that are not eas­ily dis­cov­ered using tra­di­tional physics model-based sim­u­la­tions, re­duc­ing ma­chine tun­ing up time etc among the many pos­si­ble ap­pli­ca­tions. While at APS we have many ex­cel­lent tools for the op­ti­miza­tion, di­ag­nos­tics, and con­trols of the ac­cel­er­a­tors, we do not yet have ML-based tools es­tab­lished. It is our de­sire to test ML in our ma­chine op­er­a­tion, op­ti­miza­tion, and con­trols. In this paper, we in­tro­duce the ap­pli­ca­tion of neural net­works to the APS linac bunch charge trans­mis­sion ef­fi­ciency. 		 
poster icon Poster TUPAB287 [0.781 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB287  
About • paper received ※ 12 May 2021       paper accepted ※ 16 June 2021       issue date ※ 29 August 2021  
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TUPAB290 Demonstration of Machine Learning Front-End Optimization of the Advanced Photon Source Linac linac, controls, gun, electron 2163
 
  • A. Hanuka, J.P. Duris
    SLAC, Menlo Park, California, USA
  • H. Shang, Y. Sun
    ANL, Lemont, Illinois, USA
  
  The elec­tron beam for the Ad­vanced Pho­ton Source (APS) at Ar­gonne Na­tional Lab­o­ra­tory is gen­er­ated from a thermionic RF gun and ac­cel­er­ated by an S-band lin­ear ac­cel­er­a­tor – the APS linac. While the APS linac lat­tice is set up using a model de­vel­oped with EL­E­GANT, the thermionic RF gun front-end beam dy­nam­ics have been dif­fi­cult to model. One of the is­sues is that beam prop­er­ties from thermionic guns can vary. As a re­sult, linac front-end beam tun­ing is re­quired to es­tab­lish good match­ing and max­i­mize the charge trans­ported through the linac. A tra­di­tional Nelder-Mead sim­plex op­ti­mizer has been used to find the best set­tings for the six­teen quadrupoles and steer­ing mag­nets. How­ever, it takes a long time and re­quires some fair ini­tial con­di­tions. The Gauss­ian Process (GP) op­ti­mizer does not have the ini­tial con­di­tion lim­i­ta­tion and runs sev­eral times faster. In this paper, we re­port our data col­lec­tion and analy­sis for the train­ing of the GP hy­per­pa­ra­me­ters and dis­cuss the ap­pli­ca­tion of GP op­ti­mizer on the APS linac front-end op­ti­miza­tion for max­i­mum bunch charge trans­porta­tion ef­fi­ciency through the linac.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB290  
About • paper received ※ 09 May 2021       paper accepted ※ 28 July 2021       issue date ※ 27 August 2021  
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TUPAB316 New Operational Quantities for Radiation Protection by ICRU and ICRP: Impact on Workplaces at Accelerators radiation, operation, MMI, target 2231
 
  • Th. Otto, M. Widorski
    CERN, Meyrin, Switzerland
  
  In ra­di­a­tion pro­tec­tion, Ef­fec­tive Dose E quan­ti­fies sto­chas­tic ra­di­a­tion detri­ment. E is de­fined as a weighted sum of ab­sorbed dose to or­gans and tis­sues and can­not be mea­sured di­rectly. ICRU has de­fined op­er­a­tional quan­ti­ties to mea­sure ef­fec­tive dose ap­prox­i­mately, such as Am­bi­ent dose equiv­a­lent H*(10). At high en­er­gies, the es­ti­mates pro­vided by H*(10) de­vi­ate strongly from ef­fec­tive dose. In 2020, ICRU and ICRP have rec­om­mended new op­er­a­tional quan­ti­ties for ex­ter­nal ra­di­a­tion with a de­f­i­n­i­tion close to the one of ef­fec­tive dose, and pub­lished an ex­ten­sive col­lec­tion of con­ver­sion co­ef­fi­cients from par­ti­cle flu­ence to the new quan­ti­ties (1). Am­bi­ent dose H* serves for op­er­a­tional mon­i­tor­ing pur­poses. The new de­f­i­n­i­tion al­le­vi­ates the ob­served dis­crep­an­cies of H*(10) with ef­fec­tive dose. In this paper, we pre­sent a nu­mer­i­cal study of ef­fec­tive dose E, am­bi­ent dose equiv­a­lent H*(10) and am­bi­ent dose H* in ra­di­a­tion fields at work­places at pro­ton- and elec­tron ac­cel­er­a­tors. These places in­clude lo­ca­tions be­hind pri­mary shield­ing, in ac­cess mazes and in the vicin­ity of ac­ti­vated ac­cel­er­a­tor com­po­nents.
(1) ICRU Report 95, Operational quantities for external radiation 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB316  
About • paper received ※ 11 May 2021       paper accepted ※ 02 July 2021       issue date ※ 23 August 2021  
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TUPAB318 The Beamline Safety Interlock System of Taiwan Photon Source radiation, vacuum, controls, synchrotron-radiation 2239
 
  • C.F. Chang, C.Y. Chang, C.Y. Liu, H.Y. Yan
    NSRRC, Hsinchu, Taiwan
  
  The en­ergy of syn­chro­tron ra­di­a­tion gen­er­ated by bremsstrahlung ra­di­a­tion and mag­net is rather high, which may cause se­ri­ous ra­di­a­tion dam­age to human body or even im­peril peo­ple’s life. The beam­line there­fore must be equipped with ra­di­a­tion-pro­tec­tion sys­tem; in ad­di­tion, the over­heat of op­ti­cal com­po­nents ex­posed to syn­chro­tron ra­di­a­tion will lead to the dam­age of op­ti­cal com­po­nents and de­vices. In con­se­quence, the beam­line should be fur­nished with the cool­ing-pro­tec­tion sys­tem to cool down op­ti­cal com­po­nents and de­vices. The Beam­line Safety In­ter­lock Sys­tem tar­gets at pro­tect­ing the per­son­nel and the safety of de­vices, lim­it­ing the ra­di­a­tion dose to a se­cu­rity value for ex­per­i­men­tal per­son­nel or staffs ex­pos­ing to ra­di­a­tion on the site as well as pre­vent­ing beam­line com­po­nents from being ex­posed to over­heat or vac­uum dam­ages to im­prove the ef­fec­tive­ness of beam­line.  
poster icon Poster TUPAB318 [3.440 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB318  
About • paper received ※ 09 May 2021       paper accepted ※ 10 June 2021       issue date ※ 31 August 2021  
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TUPAB340 Design of the Magnetic Shielding for 166 MHz and 500 MHz Superconducting RF Cavities at High Energy Photon Source cavity, shielding, simulation, superconducting-cavity 2289
 
  • L. Guo, Y. Chen, J. Li, Z.Q. Li, Q. Ma, P. Zhang, X.Y. Zhang, H.J. Zheng
    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.
Five 166 MHz quar­ter-wave β=1 su­per­con­duct­ing cav­i­ties and two 500 MHz sin­gle-cell el­lip­ti­cal su­per­con­duct­ing cav­i­ties have been de­signed for the stor­age ring of High En­ergy Pho­ton Source (HEPS). It is nec­es­sary to shield mag­netic field for su­per­con­duct­ing cav­i­ties to re­duce the resid­ual sur­face re­sis­tance due to mag­netic flux trap­ping dur­ing cav­ity cool down. The mag­netic shield­ing for both 166 MHz and 500 MHz su­per­con­duct­ing cav­i­ties have been de­signed. The resid­ual mag­netic field in­side the cav­i­ties have been cal­cu­lated by using Opera-3D sim­u­la­tion soft­ware. The ge­o­graphic lo­ca­tion of the cav­ity being in­stalled at the HEPS site and the fringe field of the up­stream mag­net are con­sid­ered. These are re­ported in this paper. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB340  
About • paper received ※ 18 May 2021       paper accepted ※ 17 June 2021       issue date ※ 10 August 2021  
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TUPAB346 Development of a 500-MHz 150-kW Solid-State Power Amplifier for High Energy Photon Source GUI, cavity, controls, booster 2312
 
  • Y.L. Luo, T.M. Huang, J. Li, H.Y. Lin, Q. Ma, Q.Y. Wang, P. Zhang, F.C. Zhao
    IHEP, Beijing, People’s Republic of China
  
  A 500-MHz 150-kW solid-state power am­pli­fier (SSA) has been de­vel­oped to test the 500-MHz nor­mal con­duct­ing cav­i­ties for High En­ergy Pho­ton Source (HEPS) booster ring. It will also be used to power nor­mal con­duct­ing cav­i­ties in the ini­tial beam com­mis­sion­ing stage of the HEPS stor­age ring. A total num­ber of 96 am­pli­fier mod­ules are com­bined ini­tially by coax­ial and later by wave­guide com­bin­ers to de­liver the 150-kW RF power. The final out­put is of EIA stan­dard WR1800 rec­tan­gu­lar wave­guide. Each am­pli­fier mod­ule con­sists four tran­sis­tors equipped with in­di­vid­ual cir­cu­la­tor and load and out­puts 2-kW RF power. Mod­u­lar­ity, re­dun­dancy and sat­is­fac­tory RF per­for­mance are demon­strated. In the final stage of HEPS pro­ject, this 150-kW am­pli­fier will be mod­i­fied to a 100-kW am­pli­fier to join the other five 100-kW SSAs for nor­mal op­er­a­tion of the booster cav­i­ties. The de­vel­op­ment and test re­sults are pre­sented in this paper.  
poster icon Poster TUPAB346 [1.870 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB346  
About • paper received ※ 19 May 2021       paper accepted ※ 21 June 2021       issue date ※ 15 August 2021  
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TUPAB347 Development of a 166-MHz 260-kW Solid-State Power Amplifier for High Energy Photon Source controls, status, power-supply, cavity 2315
 
  • Y.L. Luo, T.M. Huang, J. Li, H.Y. Lin, Q. Ma, Q.Y. Wang, P. Zhang, F.C. Zhao
    IHEP, Beijing, People’s Republic of China
  
  166-MHz 260-kW solid-state power am­pli­fiers have been cho­sen to drive the 166.6-MHz su­per­con­duct­ing cav­i­ties for the stor­age ring of High En­ergy Pho­ton Source. Highly mod­u­lar yet com­pact are de­sired. A total num­ber of 112 am­pli­fier mod­ules of 3 kW each are com­bined in a multi-stage power com­bin­ing topol­ogy. The final out­put is of 9-3/16" 50 Ω coax­ial rigid line. Each am­pli­fier mod­ule con­sists of 3 LDMOS tran­sis­tors with in­di­vid­ual cir­cu­la­tor and load. Ther­mal sim­u­la­tions of the am­pli­fier mod­ule have been con­ducted to op­ti­mize cool­ing ca­pa­bil­i­ties for both trav­el­ling-wave and full-re­flec­tion op­er­a­tion sce­nar­ios. High ef­fi­ciency, suf­fi­cient re­dun­dancy and ex­cel­lent RF per­for­mances of the 260-kW sys­tem are demon­strated. A con­trol sys­tem is also in­te­grated and EPICS is used to man­age the mon­i­tored data. The de­sign and test re­sults of the am­pli­fier sys­tem are pre­sented in this paper.  
poster icon Poster TUPAB347 [1.972 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB347  
About • paper received ※ 19 May 2021       paper accepted ※ 21 June 2021       issue date ※ 29 August 2021  
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TUPAB373 Design of a Delta-type Superconducting Undulator at the IHEP undulator, polarization, permanent-magnet, radiation 2391
 
  • J.H. Wei
    IHEP CSNS, Guangdong Province, People’s Republic of China
  • C.D. Deng
    DNSC, Dongguan, People’s Republic of China
  • L. Gong, X.Y. Li, X.C. Yang
    IHEP, Beijing, People’s Republic of China
  • Y. Li
    DESY, Hamburg, Germany
  
  Un­du­la­tors play an im­por­tant role in the 4th gen­er­a­tion ra­di­a­tion light source. In order to sat­isfy dif­fer­ent re­quire­ments of the ex­per­i­ments, var­i­ous un­du­la­tor struc­tures have been pro­posed. The Delta-type un­du­la­tor can pro­vide cir­cu­lar po­lar­ized ra­di­a­tion. Con­ven­tional un­du­la­tors are usu­ally made of per­ma­nent mag­nets, but the ap­pli­ca­tion of the su­per­con­duct­ing tech­nol­ogy in the un­du­la­tor is de­vel­op­ing quickly. Com­pared to the per­ma­nent mag­net un­du­la­tors, su­per­con­duct­ing un­du­la­tors can pro­vide higher pho­ton flux with the same mag­netic pole gap and pe­riod length, es­pe­cially when the pe­riod length is longer than 20 mm. An R&D pro­ject is un­der­way to pro­duce a protype of a Delta-type su­per­con­duct­ing un­du­la­tor with 28 mm long pe­riod and 12 mm gap at the IHEP. The struc­ture de­sign and the sim­u­la­tion re­sults of the mag­netic field are pre­sented in this paper.  
poster icon Poster TUPAB373 [1.752 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB373  
About • paper received ※ 19 May 2021       paper accepted ※ 18 June 2021       issue date ※ 15 August 2021  
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TUPAB375 Commissioning and Operation of Superconducting Multipole Wiggler at Siam Photon Source MMI, operation, wiggler, electron 2398
 
  • P. Sunwong, S. Boonsuya, S. Chaichuay, T. Chanwattana, Ch. Dhammatong, A. Kwankasem, C.P. Preecha, T. Pulampong, K. Sittisard, V. Sooksrimuang, S. Srichan, P. Sudmuang, N. Suradet, S. Tancharakorn
    SLRI, Nakhon Ratchasima, Thailand
  
  A new in­ser­tion de­vice, Su­per­con­duct­ing Mul­ti­pole Wig­gler (SMPW) with the peak field strength of 3.5 T, was in­stalled in the stor­age ring of Siam Pho­ton Source as a ra­di­a­tion source for a new hard X-ray beam­line. Cool-down process, as well as mag­net train­ing, was per­formed with care­ful tun­ing of liq­uid he­lium fill­ing pro­ce­dure for ef­fi­cient man­age­ment of liq­uid he­lium sup­ply. The fill­ing pro­ce­dure was also op­ti­mized for safe op­er­a­tion of the mag­net. The SMPW com­mis­sion-ing was suc­cess­fully car­ried out with elec­tron beam and the ef­fect of SMPW on elec­tron beam dy­nam­ics was ob­served. It can be min­i­mized using quadru­pole mag­nets and hor­i­zon­tal/ver­ti­cal cor­rec­tors.  
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DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB375  
About • paper received ※ 18 May 2021       paper accepted ※ 02 June 2021       issue date ※ 31 August 2021  
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TUPAB392 Conceptual Design of the Vacuum System for the Future Circular Collider FCC-ee Main Rings vacuum, collider, quadrupole, scattering 2438
 
  • R. Kersevan, C. Garion
    CERN, Geneva, Switzerland
  
  The Fu­ture Cir­cu­lar Col­lider study pro­gram com­prises sev­eral ma­chine con­cepts for the fu­ture of high-en­ergy par­ti­cle physics. Among them there is a twin-ring e−e+ col­lider ca­pa­ble to run at beam en­er­gies be­tween 45.6 and 182.5 GeV, i.e. the en­er­gies cor­re­spond­ing to the res­o­nances of the Z, W, H bosons and the top quark. The con­cep­tual de­sign of the two 100-km rings has ad­vanced to what is be­lieved to be a work­ing so­lu­tion, i.e. ca­pa­bil­ity to deal with low-en­ergy (45.6 GeV) high-cur­rent (1390 mA) ver­sion as well as the high-en­ergy (182.5 GeV) low-cur­rent (5.4 mA) one, with in­ter­me­di­ate en­ergy and cur­rent steps for the other 2 res­o­nances. The limit for all of the ver­sions is given by the 50 MW/beam al­lot­ted to the syn­chro­tron ra­di­a­tion (SR) losses. The paper will out­line the main beam/ma­chine pa­ra­me­ters, the vac­uum re­quire­ments, and the choices made con­cern­ing the vac­uum cham­ber geom­e­try, ma­te­r­ial, sur­face treat­ments, pump­ing sys­tem, and the re­lated pres­sure pro­files. The lo­ca­tion of lumped SR pho­ton ab­sorbers for the generic arc cell has been de­ter­mined. An out­line of the stud­ies needed and en­vis­aged for the near fu­ture will also be given.  
poster icon Poster TUPAB392 [3.036 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB392  
About • paper received ※ 19 May 2021       paper accepted ※ 31 May 2021       issue date ※ 25 August 2021  
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TUPAB404 Monte Carlo Studies for Shielding Design for High Energy Linac for Medical Isotope Generation neutron, shielding, radiation, target 2469
 
  • N. Upadhyay, S. Chacko
    University of Mumbai, Mumbai, India
  • A.P. Deshpande, T.S. Dixit, P.S. Jadhav, R. Krishnan
    SAMEER, Mumbai, India
  
  The widely used ra­dioac­tive tracer Tech­netium-99m (99mTc) is tra­di­tion­ally pro­duced from Ura­nium via 235U (n, f) 99Mo re­ac­tions which de­pends heav­ily on nu­clear re­ac­tors. De­sign stud­ies for an al­ter­na­tive, cleaner ap­proach for ra­dioiso­tope gen­er­a­tion using a high en­ergy elec­tron linac were ini­ti­ated at SAMEER to gen­er­ate 99Mo. The elec­tron beam from a 30 MeV linac with an av­er­age cur­rent of 350 µA will be bom­barded on a con­ver­tor tar­get to pro­duce X-rays which will be bom­barded on en­riched 100Mo tar­get to pro­duce 99Mo via (g, n) re­ac­tion. 99mTc will be eluted from 99Mo. The pho­tons and neu­trons pro­duced in the process should be shielded ap­pro­pri­ately to en­sure ra­di­a­tion safety. This paper brings out the use of Monte Carlo tech­niques for pho­ton and neu­tron shield­ing for our ap­pli­ca­tion. We used FLUKA to cal­cu­late the flu­ence, an­gu­lar dis­tri­b­u­tion and dose for pho­tons and neu­trons. Then, we in­tro­duced var­i­ous lay­ers of lead fol­lowed by HDPE, 5% bo­rated HDPE and 40% boron rub­ber to en­sure that the pro­posed shield­ing is suf­fi­cient to com­pletely shield the pho­ton as well as neu­tron ra­di­a­tion and hence is safe for op­er­a­tion.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB404  
About • paper received ※ 19 May 2021       paper accepted ※ 22 June 2021       issue date ※ 25 August 2021  
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TUPAB409 FLUKA and Geant4 Monte Carlo Simulations of a Desktop, Flat Panel Source Array for 3D Medical Imaging simulation, electron, experiment, detector 2483
 
  • T. Primidis, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • T. Primidis, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • V. Soloviev
    Adaptix Imaging, Didcot, United Kingdom
  
  Funding: Funded by the Accelerators for Security, Healthcare and Environment CDT from the United Kingdom Research and Innovation Science and Technology Facilities Council, reference ID ST/R002142/1
Dig­i­tal to­mosyn­the­sis (DT) is a 3D imag­ing modal­ity with a lower cost and lower dose than com­puted to­mog­ra­phy. A DT sys­tem made of a flat panel array with 45 X-ray sources, but com­pact enough to fit on the desk­top is near mar­ket re­al­i­sa­tion by the com­pany Adap­tix Ltd. This work pre­sents a frame­work of FLUKA and Geant4 Monte Carlo (MC) sim­u­la­tions of the Adap­tix sys­tem in­clud­ing the X-ray beam gen­er­a­tion and the final image qual­ity. The re­sults show that MC meth­ods offer an in­sight into the per­for­mance de­tails of such an in­no­v­a­tive de­vice at dif­fer­ent lev­els be­tween the X-ray emit­ter array and the de­tec­tor. As such, a large por­tion of the de­sign and op­ti­mi­sa­tion of such novel X-ray imag­ing sys­tems can be done with a sin­gle toolkit. Fi­nally, the mod­u­lar­ity of the ap­proach al­lows other tools to be im­ported at var­i­ous steps within the frame­work and thus pro­vide an­swers to ques­tions that can­not be ad­dressed by gen­eral-pur­pose MC codes. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB409  
About • paper received ※ 17 May 2021       paper accepted ※ 31 May 2021       issue date ※ 24 August 2021  
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TUPAB410 Finite Element Analysis and Experimental Validation of Low-Pressure Beam Windows for XCET Detectors at CERN experiment, Windows, detector, background 2487
 
  • J. Buesa Orgaz, M. Brugger, G. Romagnoli, O. Sacristan De Frutos, F. Sanchez Galan
    CERN, Meyrin, Switzerland
  
  In the frame­work of the ren­o­va­tion and con­sol­i­da­tion of ex­per­i­men­tal areas at CERN, a low-pres­sure de­sign beam su­per­im­posed win­dows (250 µm Mylar and 150 µm poly­eth­yl­ene) for the Thresh­old Cherenkov coun­ters (XCET) has been mod­elled and ver­i­fied for its im­ple­men­ta­tion. The XCET is a de­tec­tor used to count the num­ber of se­lected charged par­ti­cles in the beam by ad­just­ing the pres­sure that leads to the emis­sion of Cherenkov pho­tons only above cer­tain pres­sure thresh­old. Si­mul­ta­ne­ously, the charged par­ti­cles pass from a vac­uum en­vi­ron­ment to the pres­sur­ized re­frac­tive gas ves­sel through a solid in­ter­face. Min­i­mal ma­te­r­ial in this solid in­ter­face is there­fore cru­cial to avoid in­ter­ac­tions of the low-en­ergy par­ti­cles which may lead to beam in­ten­sity loss or back­ground pro­duc­tion. Hence, thin and low-den­sity ma­te­ri­als are re­quired to mit­i­gate mul­ti­ple scat­ter­ing and en­ergy loss of the in­com­ing par­ti­cles while still al­low­ing the needed pres­sures in­side the counter ves­sel. A XCET val­i­da­tion method­ol­ogy was con­ducted using Fi­nite El­e­ment Analy­sis (FEA), fol­lowed by ex­per­i­men­tal val­i­da­tions per­form­ing burst pres­sure tests and using Dig­i­tal Image Cor­re­la­tion (DIC).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB410  
About • paper received ※ 19 May 2021       paper accepted ※ 02 June 2021       issue date ※ 24 August 2021  
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WEXC04 Simulations of Beam Strikes on Advanced Photon Source Upgrade Collimators using FLASH, MARS, and elegant simulation, electron, storage-ring, 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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WEXC05 First Results Operating a Long-Period EPU in Universal Mode at the Canadian Light Source polarization, focusing, undulator, injection 2566
 
  • W.A. Wurtz, C.K. Baribeau, D. Bertwistle, M.J. Sigrist
    CLS, Saskatoon, Saskatchewan, Canada
  
  The Quan­tum Ma­te­ri­als Spec­troscopy Cen­tre beam­line at the Cana­dian Light Source (CLS) re­quires pho­tons with en­er­gies as low as 15 eV with cir­cu­lar po­lar­iza­tion at the end sta­tion. This en­ergy range is ac­com­plished on the 2.9 GeV CLS stor­age ring using an el­lip­ti­cally po­lar­iz­ing un­du­la­tor (EPU) with a 180 mm pe­riod, which we call EPU180. In order to re­al­ize cir­cu­lar po­lar­ized pho­tons at the end sta­tion with this low en­ergy, we must over­come two tech­ni­cal is­sues. First, the beam­line op­tics dis­tort the po­lar­iza­tion of the light, so we com­pen­sate by pro­vid­ing light with a flat­tened, tilted po­lar­iza­tion el­lipse at the source point - a mode of op­er­a­tion known as uni­ver­sal mode. Sec­ond, the de­vice has a strong ef­fect on the elec­tron beam due to dy­namic fo­cus­ing and is ca­pa­ble of re­duc­ing the in­jec­tion ef­fi­ciency to zero. We over­come this non-lin­ear dy­namic fo­cus­ing using cur­rent strips ad­hered to the vac­uum cham­ber. In this re­port, we pre­sent the first re­sults with op­er­at­ing EPU180 in uni­ver­sal mode and we re­cover the dy­namic aper­ture using the cur­rent strips.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEXC05  
About • paper received ※ 13 May 2021       paper accepted ※ 05 July 2021       issue date ※ 11 August 2021  
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WEPAB021 Development and Testing of a Cherenkov Beam Loss Monitor in CLEAR Facility experiment, detector, electron, beam-losses 2640
 
  • S. Benitez Berrocal, E. Effinger, W. Farabolini, A. Gilardi, P. Korysko, E. Lima, B. Salvachua, W. Viganò
    CERN, Geneva 23, Switzerland
  • P. Lane
    University of Huddersfield, Huddersfield, United Kingdom
  
  Beam Loss Mon­i­tors are fun­da­men­tal di­ag­nos­tic sys­tems in par­ti­cle ac­cel­er­a­tors. Beam losses are mea­sured by a wide range of de­tec­tors with ex­cel­lent re­sults; most of these de­vices are used to mea­sure local beam losses. How­ever, in some ac­cel­er­a­tors there is the need to mea­sure beam losses con­tin­u­ously lo­cal­ized over longer dis­tances i.e., sev­eral tens of me­ters. For this rea­son, a beam loss de­tec­tor based on long op­ti­cal fi­bres is now under study. As part of the de­sign, sev­eral sim­u­la­tions, com­par­ing dif­fer­ent pos­si­ble de­tec­tion sce­nar­ios, have been per­formed in FLUKA and bench-marked with ex­per­i­men­tal data. An ex­per­i­men­tal cam­paign was per­formed with an elec­tron beam in the CERN Lin­ear Elec­tron Ac­cel­er­a­tor for Re­search (CLEAR) in No­vem­ber 2020. The light emit­ted from the op­ti­cal fibre was cap­tured using Sil­i­con Photo-Mul­ti­pli­ers (SiPM) cou­pled at each fibre’s end. In this poster, the first re­sults of a beam loss de­tec­tor based on the cap­ture of Cherenkov pho­tons gen­er­ated by charged par­ti­cles in­side mul­ti­mode sil­ica fi­bres are pre­sented.  
poster icon Poster WEPAB021 [0.724 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB021  
About • paper received ※ 18 May 2021       paper accepted ※ 21 June 2021       issue date ※ 31 August 2021  
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WEPAB029 Challenges for the Interaction Region Design of the Future Circular Collider FCC-ee detector, simulation, background, collider 2668
 
  • M. Boscolo, A. Ciarma, F. Fransesini, L. Pellegrino
    INFN/LNF, Frascati, Italy
  • N. Bacchetta
    INFN- Sez. di Padova, Padova, Italy
  • M. Benedikt, H. Burkhardt, M.A. Jones, R. Kersevan, M. Lueckhof, E. Montbarbon, K. Oide, L. Watrelot, F. Zimmermann
    CERN, Meyrin, Switzerland
  • L. Brunetti, M. Serluca
    IN2P3-LAPP, Annecy-le-Vieux, France
  • M. Dam
    NBI, København, Denmark
  • M. Koratzinos
    MIT, Cambridge, Massachusetts, USA
  • M. Migliorati
    INFN-Roma1, Rome, Italy
  • A. Novokhatski, M.K. Sullivan
    SLAC, Menlo Park, California, USA
  • F. Poirier
    CNRS - DR17, RENNES, France
  
  Funding: This work was partially supported by the EC HORIZON 2020 project FCC-IS, grant agreement n.951754, and by the U. S. Department of Energy, Office of Science, under Contract No. DE-AC02-76SF-00515.
The FCC-ee is a pro­posed fu­ture high-en­ergy, high-in­ten­sity and high pre­ci­sion lep­ton col­lider. Here, we pre­sent the lat­est de­vel­op­ments for the FCC-ee in­ter­ac­tion re­gions, which shall en­sure op­ti­mum con­di­tions for the par­ti­cle physics ex­per­i­ments. We dis­cuss mea­sures of back­ground re­duc­tion and a re­vised in­ter­ac­tion re­gion lay­out in­clud­ing a low im­ped­ance com­pact beam cham­ber de­sign. We also dis­cuss the pos­si­ble im­pact of the ra­di­a­tion gen­er­ated in the in­ter­ac­tion re­gion in­clud­ing beam­strahlung. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB029  
About • paper received ※ 11 May 2021       paper accepted ※ 23 June 2021       issue date ※ 30 August 2021  
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WEPAB062 Investigation of the Thomson Scattering Influence on Electron Beam Parameters in an Energy-Recovering Linear Accelerator on the Example of MESA electron, scattering, HOM, laser 2732
 
  • C.L. Lorey, K. Aulenbacher, A. Meseck
    KPH, Mainz, Germany
  
  Funding: funded by DFG through GRK2128 ACCELENCE
At the Jo­hannes Guten­berg Uni­ver­sity (JGU) in Mainz, the Mainz En­ergy-re­cov­er­ing Su­per­con­duct­ing Ac­cel­er­a­tor (MESA) is cur­rently under con­struc­tion. It is de­signed to de­liver elec­tron beams of up to 155 MeV. As it can be op­er­ated in an en­ergy-re­cov­ery (ER) mode thus al­low­ing for high rep­e­ti­tion rate, it is a promis­ing can­di­date for a high flux Thom­son scat­ter­ing based gamma source. This paper will pro­vide a sta­tus up­date on the study of the im­pact of Thom­son scat­ter­ing on elec­tron beam pa­ra­me­ters and the un­der­ly­ing me­chan­ics. Fur­ther, the im­ple­men­ta­tion into a sim­u­la­tion code will be dis­cussed. 		 
poster icon Poster WEPAB062 [1.307 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB062  
About • paper received ※ 19 May 2021       paper accepted ※ 12 July 2021       issue date ※ 02 September 2021  
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WEPAB067 High Duty Cycle EUV Radiation Source Based on Inverse Compton Scattering laser, electron, gun, emittance 2748
 
  • R. Huang, Q.K. Jia, C. Li
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  
  Funding: Work supported by the National Natural Science Foundation of China Grant Number 11805200, and National Key Research and Development Program of China No. 2016YFA0401901.
ICS can ob­tain quasi-mono­chro­matic and di­rec­tional EUV ra­di­a­tion via a MeV-scale en­ergy elec­tron beam and a mi­cron-scale wave­length laser beam, which en­ables a dra­matic re­duc­tion in di­men­sion and ex­pense of the sys­tem, and makes it an at­trac­tive tech­nol­ogy in re­search, in­dus­try, med­i­cine and home­land se­cu­rity. Here we de­scribe an EUV source based on high rep­e­ti­tion ICS sys­tem. The scheme ex­ploits the out­put from the laser-elec­tron in­ter­ac­tion be­tween a MW-ps laser at MHz rep­e­ti­tion-rate and a high qual­ity elec­tron beam with an en­ergy of a few MeV at MHz rep­e­ti­tion-rate. 		 
poster icon Poster WEPAB067 [1.551 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB067  
About • paper received ※ 23 May 2021       paper accepted ※ 24 June 2021       issue date ※ 02 September 2021  
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WEPAB075 Xenos: X-Ray Monte Carlo Code Suite electron, simulation, positron, operation 2766
 
  • S. Humphries
    Field Precision, Albuquerque, New Mexico, USA
  
  Xenos is an in­te­grated 3D code suite for the de­sign of X-ray sources and elec­tron beam de­vices. The com­po­nent pro­grams run under all ver­sions of Win­dows. This paper de­scribes unique fea­tures of Xenos com­pared to other Monte Carlo pack­ages: 1) rep­re­sen­ta­tion of geom­e­try and de­posited dose on a fi­nite-el­e­ment mesh sup­ported by an in­ter­ac­tive mesh gen­er­a­tor, 2) in­clu­sion of full 3D elec­tric and mag­netic fields in Monte Carlo sim­u­la­tions, 3) an in­te­grated user en­vi­ron­ment for input and out­put cal­cu­la­tions (e.g., elec­tron gun de­sign, tar­get heat­ing, …) and 4) ex­tended par­al­lel-com­put­ing sup­port for high-ac­cu­racy so­lu­tions. Xenos em­ploys the full ca­pa­bil­i­ties of multi-core com­put­ers and al­lows par­al­lel com­pu­ta­tions on an un­lim­ited num­ber of in­de­pen­dent com­put­ers.
* Sempau J., et.al. (2003), "Experimental benchmarks of the Monte Carlo code PENELOPE", Nucl. Instrum. Meth. B 207, 107-123. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB075  
About • paper received ※ 10 May 2021       paper accepted ※ 23 June 2021       issue date ※ 25 August 2021  
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WEPAB080 Near Threshold Pion Photoproduction on Deuterons experiment, multipole, polarization, scattering 2775
 
  • V. Shastri, V. Aswathi, S.P. Shilpashree
    Christ University, School of Engineering and Technology, Bangalore, India
  
  The study of pho­to­pro­duc­tion of mesons is a prime tool in un­der­stand­ing the prop­er­ties of strong in­ter­ac­tions. The only pho­to­pro­duc­tion re­ac­tion on deuteron with two-body final state is co­her­ent pion pho­to­pro­duc­tion re­ac­tion. Sev­eral the­o­ret­i­cal stud­ies are being car­ried out on the pion pho­to­pro­duc­tion on deuterons since sev­eral decades. On the ex­per­i­men­tal side, the ac­cel­er­a­tor and de­tec­tor tech­nol­ogy has im­proved the de­vel­op­ments. In the re­cent years, mea­sure­ments of ten­sor an­a­lyz­ing pow­ers as­so­ci­ated with co­her­ent and in­co­her­ent pion pho­to­pro­duc­tion are also being car­ried out at the VEPP-3 elec­tron stor­age ring. In one of the re­cent mea­sure­ments, Rachek et al"*" have ob­served dis­crep­ancy be­tween the­ory and ex­per­i­ment at higher pho­ton en­er­gies and have sug­gested for im­prove­ment of the the­o­ret­i­cal mod­els. In a more re­cent analy­sis,"**" the role of D-wave com­po­nent on spin asym­me­tries have been iden­ti­fied. In view of these de­vel­op­ments, the pur­pose of the pre­sent con­tri­bu­tion is to study co­her­ent pion pho­to­pro­duc­tion on deuterons using model in­de­pen­dent ir­re­ducible ten­sor for­mal­ism de­vel­oped ear­lier to study the pho­to­dis­in­te­gra­tion of deuterons."***"
*I A Rachek et al., Few-Body Syst., 58, 29 (2017)
**H M Al Ghamdi et al, Brazillian Journal of Physics, 50, 615 (2020)
*** G Ramachandran, S P Shilpashree Phys. Rev. C 74, 052801(R) (2006) 		 
poster icon Poster WEPAB080 [0.203 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB080  
About • paper received ※ 29 May 2021       paper accepted ※ 01 July 2021       issue date ※ 16 August 2021  
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WEPAB087 Observation of Undulator Radiation Generated by a Single Electron Circulating in a Storage Ring and Possible Applications synchrotron, electron, radiation, undulator 2790
 
  • I. Lobach
    University of Chicago, Chicago, Illinois, USA
  • A. Halavanau, Z. Huang
    SLAC, Menlo Park, California, USA
  • K. Kim
    ANL, Lemont, Illinois, USA
  • S. Nagaitsev, A.L. Romanov, G. Stancari, A. Valishev
    Fermilab, Batavia, Illinois, USA
  
  An ex­per­i­men­tal study into the un­du­la­tor ra­di­a­tion, gen­er­ated by a sin­gle elec­tron was car­ried out at the In­te­grable Op­tics Test Ac­cel­er­a­tor (IOTA) stor­age ring at Fer­mi­lab. The in­di­vid­ual pho­tons were de­tected by a Sin­gle Pho­ton Avalanche Diode (SPAD) at an av­er­age rate of 1 de­tec­tion per 300 rev­o­lu­tions in the ring. The de­tec­tion events were con­tin­u­ously recorded by a pi­cosec­ond event timer for as long as 1 minute at a time. The col­lected data were used to test if there is any de­vi­a­tion from the clas­si­cally pre­dicted Pois­son­ian pho­to­sta­tis­tics. It was mo­ti­vated by the ob­ser­va­tion * of sub-Pois­son­ian sta­tis­tics in a sim­i­lar ex­per­i­ment. The ob­ser­va­tion * could be an in­stru­men­ta­tion ef­fect re­lated to low de­tec­tion ef­fi­ciency and long de­tec­tor dead time. In our ex­per­i­ment, the de­tec­tor (SPAD) has a much higher ef­fi­ciency (65%) and a much lower dead time. In ad­di­tion, we show that the col­lected data (recorded de­tec­tion times) can be used to study the syn­chro­tron mo­tion of a sin­gle elec­tron and infer some pa­ra­me­ters of the ring. For ex­am­ple, by com­par­ing the re­sults of sim­u­la­tion and mea­sure­ment for the syn­chro­tron mo­tion we were able to es­ti­mate the mag­ni­tude of the RF phase jit­ter.
* Teng Chen and John M. J. Madey, Phys. Rev. Lett. 86, 5906, June 2001 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB087  
About • paper received ※ 17 May 2021       paper accepted ※ 24 June 2021       issue date ※ 16 August 2021  
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WEPAB099 Near-Threshold Nonlinear Photoemission From Cu(100) electron, laser, cathode, experiment 2822
 
  • C.J. Knill, S.S. Karkare
    Arizona State University, Tempe, USA
  • H.A. Padmore
    LBNL, Berkeley, California, USA
  
  Funding: National Science Foundation Grant No. PHY-1549132
Pho­to­cath­odes that have a low mean trans­verse en­ergy (MTE) are cru­cial to the de­vel­op­ment of com­pact X-ray Free Elec­tron Lasers (XFEL) and ul­tra­fast elec­tron dif­frac­tion (UED) ex­per­i­ments. For FELs, low MTE cath­odes re­sult in a lower re­quire­ment for elec­tron en­ergy when las­ing at a de­fined en­ergy, and for a de­fined elec­tron en­ergy re­sult in las­ing at higher en­ergy. For UED ex­per­i­ments, low MTE cath­odes give a longer co­her­ence length, al­low­ing mea­sure­ments on larger unit cell ma­te­ri­als. A record low MTE of 5 meV has been re­cently demon­strated from a Cu (100) sur­face when mea­sured near the pho­toe­mis­sion thresh­old and cooled down to 30 K with liq­uid He­lium [*]. For UED and XFEL ap­pli­ca­tions that re­quire a high charge den­sity, the low quan­tum ef­fi­ciency of Cu (100) near thresh­old ne­ces­si­tates the use of a high laser flu­ence to achieve the de­sired charge den­sity [**]. At high laser flu­ences the MTE is lim­ited by non­lin­ear ef­fects, and there­fore it is nec­es­sary to in­ves­ti­gate near pho­toe­mis­sion thresh­old at these high laser flu­ences. In this paper we re­port on non­lin­ear, near-thresh­old pho­toe­mis­sion from a Cu (100) cath­ode, and its ef­fect on the MTE.
* S. Karkare et al, Phys. Rev. Lett. 125, 054801 (2020)
** J. Bae et al, J. Appl. Phys., 124, 244903 (2018) 		 
poster icon Poster WEPAB099 [0.829 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB099  
About • paper received ※ 19 May 2021       paper accepted ※ 21 July 2021       issue date ※ 29 August 2021  
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WEPAB112 Performance Characterisation of a Cu (100) Single-Crystal Photocathode cathode, electron, emittance, experiment 2860
 
  • L.A.J. Soomary, D.P. Juarez-Lopez, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • L.B. Jones, T.C.Q. Noakes
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  
  The search for high per­for­mance pho­to­cath­ode elec­tron sources is a pri­or­ity in the ac­cel­er­a­tor sci­ence com­mu­nity. The sur­face char­ac­ter­is­tics of a pho­to­cath­ode de­fine im­por­tant fac­tors of the pho­toe­mis­sion in­clud­ing the in­trin­sic emit­tance, the quan­tum ef­fi­ciency and the work func­tion of the pho­to­cath­ode. These fac­tors in turn de­fine the elec­tron beam per­for­mance which are mea­sur­able as emit­tance, bright­ness and en­ergy spread. We have used ASTeC’s Mul­ti­probe (SAPI)* to char­ac­terise and analyse pho­to­cath­ode per­for­mance using mul­ti­ple tech­niques in­clud­ing XPS, STM, and LEED imag­ing, and their Trans­verse En­ergy Spread Spec­trom­e­ter (TESS)** to mea­sure mean trans­verse en­ergy (MTE). We pre­sent char­ac­ter­i­sa­tion mea­sure­ments for a Cu (100) sin­gle-crys­tal pho­to­cath­ode sam­ple with data from SAPI con­firm­ing the crys­tal­lo­graphic face and show­ing sur­face com­po­si­tion and rough­ness, sup­ported by data from TESS show­ing the pho­to­cath­ode elec­tron beam en­ergy spread.
* B.L. Militsyn, 4-th EuCARD2 WP12.5 meeting, Warsaw, 14-15 March 2017
**Proc. FEL’13, TUPPS033, 290-293
 		 
poster icon Poster WEPAB112 [0.814 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB112  
About • paper received ※ 19 May 2021       paper accepted ※ 12 July 2021       issue date ※ 22 August 2021  
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WEPAB127 Accurate Measurements of Undulator Particle Beam Entrance/Exit Angles Using Improved Hall Probes and Calibration Process undulator, insertion, insertion-device, closed-orbit 2907
 
  • I. Vasserman, R.J. Dejus, Y. Piao, M.F. Qian, 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) un­du­la­tor re­quire­ments were changed from the first and sec­ond field in­te­grals to the en­trance and exit an­gles of the par­ti­cle beam. This pro­vides the user with the best ra­di­a­tion view angle by the stor­age ring closed orbit cor­rec­tion sys­tem. To sat­isfy such re­quire­ments we use im­proved Senis Hall probes and cal­i­bra­tion process. In ad­di­tion to the nor­mal NMR cal­i­bra­tion of the sen­sors, the cal­i­bra­tion was fur­ther re­fined using stretch-coil in­te­grals to make ac­cu­rate mea­sure­ments. 		 
poster icon Poster WEPAB127 [0.620 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB127  
About • paper received ※ 15 May 2021       paper accepted ※ 09 June 2021       issue date ※ 19 August 2021  
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WEPAB128 Recent Experience with Magnet Sorting for APS-U Hybrid Undulators undulator, quadrupole, permanent-magnet, synchrotron 2910
 
  • I. Vasserman, R.J. Dejus, Y. Piao, M.F. Qian, 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 qual­ity of per­ma­nent mag­nets plays a par­tic­u­larly im­por­tant role in un­du­la­tor per­for­mance. Many dif­fer­ent types of mag­net sort­ing to en­hance un­du­la­tor per­for­mance have been car­ried out at dif­fer­ent fa­cil­i­ties. Mean­while, progress in im­prov­ing mag­net qual­ity has been made by dif­fer­ent ven­dors. At the Ad­vanced Pho­ton Source (APS) we have as­sem­bled, mea­sured, and an­a­lyzed over 14 new un­du­la­tors of the same me­chan­i­cal de­sign, some of them with sorted mag­nets and some un­sorted. The per­for­mance dif­fer­ences ap­pear to be in­signif­i­cant in meet­ing the tight APS Up­grade (APS-U) un­du­la­tor re­quire­ments. 		 
poster icon Poster WEPAB128 [0.395 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB128  
About • paper received ※ 16 May 2021       paper accepted ※ 09 June 2021       issue date ※ 10 August 2021  
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WEPAB132 Towards a Superconducting Undulator Afterburner for the European XFEL FEL, undulator, electron, vacuum 2921
 
  • S. Casalbuoni, J.E. Baader, G. Geloni, V. Grattoni, D. La Civita, C. Lechner, B. Marchetti, S. Serkez, H. Sinn
    EuXFEL, Schenefeld, Germany
  • W. Decking, L. Lilje, S. Liu, T. Wohlenberg, I. Zagorodnov
    DESY, Hamburg, Germany
  
  We pro­pose to de­velop, char­ac­ter­ize and op­er­ate a su­per­con­duct­ing un­du­la­tor (SCU) af­ter­burner con­sist­ing of 5 un­du­la­tor mod­ules (1 mod­ule = 2 times SCU coil of 2 m length and 1 phase shifter) at the SASE2 hard X-ray beam­line of Eu­ro­pean XFEL. This af­ter­burner has the po­ten­tial to pro­duce an out­put of more than 1010 ph/pulse at pho­ton en­er­gies above 30 keV. The pro­ject is di­vided into the pro­duc­tion of a pre-se­ries pro­to­type mod­ule and a small-se­ries pro­duc­tion of 5 mod­ules. Cen­tral goals of this R&D ac­tiv­ity are: the demon­stra­tion of the func­tion­al­ity of SCUs at an X-ray FEL, the set up of the needed in­fra­struc­ture to char­ac­ter­ize and op­er­ate SCUs, the in­dus­tri­al­iza­tion of such un­du­la­tors, and the re­duc­tion of the price per mod­ule. In this con­tri­bu­tion, the main pa­ra­me­ters and spec­i­fi­ca­tions of the pre-se­ries pro­to­type mod­ule (S-PRESSO) are de­scribed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB132  
About • paper received ※ 15 May 2021       paper accepted ※ 05 July 2021       issue date ※ 14 August 2021  
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WEPAB209 Review of Medical Accelerator Development at Sameer, India linac, electron, cavity, acceleration 3113
 
  • T.S. Dixit, N. Bansode, A.P. Bhagwat, S.T. Chavan, A.P. Deshpande, G. Gaikwad, S. Ghosh, R. Krishnan, C.S. Nainwad, G.D. Panchal, S.N. Pethe, K.A. Thakur, V.B. Ukey, M.M. Vidwans
    SAMEER, Mumbai, India
  
  Funding: Ministry of Electronics and Information Technology (MeitY), Government of India
At the Med­ical Elec­tron­ics Di­vi­sion of SAMEER, R&D for the de­vel­op­ment of a 4 MeV en­ergy elec­tron linac for Can­cer ther­apy was taken up in the late ’80s. An S-band stand­ing wave side cou­pled struc­ture op­er­at­ing at pi/2 mode was de­vel­oped for elec­tron ac­cel­er­a­tion. The linac was in­te­grated with other sub­sys­tems in col­lab­o­ra­tion with CSIO and PGIMER and the first ma­chine was com­mis­sioned at PGI, Chandi­garh in 1990. There­after, a lot of mod­i­fi­ca­tions like en­ergy, dose rate, iso-cen­ter height etc. were made in the sys­tem, and later 4 more ma­chines were com­mis­sioned in hos­pi­tals for treat­ment. More than 1,50,000 pa­tients have been treated using SAMEER’s 6 MeV on­col­ogy sys­tem. Sub­se­quently, de­vel­op­ment of dual-mode and vari­able en­ergy elec­tron and pho­ton out­put ma­chines was un­der­taken. Two-pho­ton en­er­gies of 6 and 15 MV and mul­ti­ple elec­tron en­er­gies start­ing from 6 to 18 MeV for treat­ment was of­fered from the linac. The elec­tron en­ergy vari­a­tion was done using plunger mech­a­nism in the side cou­pling cav­ity. This linac was suc­cess­fully baked and RF tested for var­i­ous pa­ra­me­ters. This paper de­scribes the ex­per­i­men­tal pa­ra­me­ters achieved for both low and high en­ergy dual-mode linac. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB209  
About • paper received ※ 14 May 2021       paper accepted ※ 07 July 2021       issue date ※ 13 August 2021  
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WEPAB255 Simulation Studies on the Interactions of Electron Beam with Wastewater electron, radiation, simulation, target 3236
 
  • X. Li, H. Baumgart, G. Ciovati
    ODU, Norfolk, Virginia, USA
  • G. Ciovati, F.E. Hannon, S. Wang
    JLab, Newport News, Virginia, USA
  
  Funding: Jefferson Lab LDRD
The man­u­fac­tured chem­i­cal pol­lu­tants, like 1,4 diox­ane and PFAS (per- and polyfluro­ralkyl sub­stances), found in the un­der­ground water and/or drink­ing water are chal­leng­ing to be re­moved or biode­graded. En­er­getic elec­trons are ca­pa­ble of me­di­at­ing and re­mov­ing them. This paper uti­lizes FLUKA code to eval­u­ate the beam-waste­water in­ter­ac­tion ef­fects with dif­fer­ent en­ergy, space and di­ver­gence dis­tri­b­u­tions of the elec­tron beam. With 8 MeV av­er­age en­ergy, the elec­tron beam exits from a 0.0127 cm thick ti­ta­nium win­dow, trav­els through a 4.3 cm dis­tance air and a sec­ond 0.0127 cm thick stain­less water con­tainer win­dow with 2.43 cm ra­dius, and fi­nally is in­jected into the water area, where the vol­ume of water is around 75 cubic cm. The dis­tri­b­u­tion pa­ra­me­ters of the elec­tron beam are from the GPT (Gen­eral Par­ti­cle Tracer) sim­u­la­tions for UITF (Up­graded In­jec­tor Test Fa­cil­ity) in Jef­fer­son lab. By vary­ing the dis­tri­b­u­tions, sev­eral mea­sure­ments in­clud­ing the dose (or en­ergy de­po­si­tion) dis­tri­b­u­tion, elec­tron flu­ence, pho­ton flu­ence are scored and com­pared. Tak­ing the com­par­isons into con­sid­er­a­tion, this paper is aim­ing to find bet­ter elec­tron beams for the waste­water ir­ra­di­a­tion. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB255  
About • paper received ※ 20 May 2021       paper accepted ※ 25 June 2021       issue date ※ 14 August 2021  
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WEPAB340 Pressure Simulations for the EIC Interaction Region vacuum, electron, detector, simulation 3483
 
  • M.L. Stutzman
    JLab, Newport News, Virginia, USA
  
  Back­ground de­tec­tor rates in the Elec­tron Ion Col­lider de­pend in part on the pres­sure in the in­ter­ac­tion re­gion. Ma­te­ri­als choice, syn­chro­tron ra­di­a­tion in­duced des­orp­tion, con­di­tion­ing time and pump­ing con­fig­u­ra­tion all af­fect the pres­sure in the sys­tem. Sim­u­la­tions of the re­gion using Syn­rad and Molflow+ cou­pled sim­u­la­tion codes will be pre­sented for var­i­ous con­fi­gru­a­tions and con­di­tion­ing times.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB340  
About • paper received ※ 18 May 2021       paper accepted ※ 20 July 2021       issue date ※ 11 August 2021  
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WEPAB402 Status and Progress of the High-Power RF System for High Energy Photon Source cavity, booster, GUI, storage-ring 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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WEPAB405 Supercontinuum Generation for the Improvement of Pulse Radiolysis System laser, radiation, polarization, electron 3657
 
  • M. Sato, Y. Kaneko, Y. Koshiba, M. Washio
    RISE, Tokyo, Japan
  • K. Sakaue
    The University of Tokyo, Graduate School of Engineering, Bunkyo, Japan
  
  Pulse ra­di­ol­y­sis is one of the ab­sorp­tion mea­sure­ment meth­ods for in­ves­ti­gat­ing the fun­da­men­tal, ul­tra­fast process of ra­di­a­tion chem­i­cal re­ac­tions. An­a­lyt­i­cal light is trans­mit­ted si­mul­ta­ne­ously with the tim­ing of elec­tron beam ir­ra­di­a­tion, and its ab­sorp­tion by re­ac­tive species is de­tected. Since the tar­get re­ac­tions arise in pico sec­ond time scale or even shorter, an­a­lyt­i­cal light is re­quired to have such du­ra­tion. Be­sides, so as not to be buried in noise of the ra­di­a­tion source, the op­ti­cal power of the an­a­lyt­i­cal light must be high enough. Fur­ther­more, it is de­sir­able that the an­a­lyt­i­cal light cov­ers vis­i­ble re­gion be­cause im­por­tant ab­sorp­tions caused by ir­ra­di­a­tion prod­ucts such as hy­drated elec­tron, hy­droxyl rad­i­cal, or so exist in the re­gion. We con­sid­ered that the su­per­con­tin­uum light gen­er­ated from an ul­tra­short pulse laser is suit­able as an an­a­lyt­i­cal light be­cause it has all these char­ac­ter­is­tics. In this study, we gen­er­ate the sec­ond har­monic (775 nm) of an er­bium fiber laser (1550 nm) as a seed laser for su­per­con­tin­uum gen­er­a­tion. In this pre­sen­ta­tion, we re­port the cur­rent sit­u­a­tion of our laser sys­tem and prospects.  
poster icon Poster WEPAB405 [0.734 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB405  
About • paper received ※ 18 May 2021       paper accepted ※ 01 September 2021       issue date ※ 20 August 2021  
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THPAB009 A Hard X-Ray Compton Source at CBETA electron, laser, scattering, brilliance 3765
 
  • K.E. Deitrick, C. Franck, G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • J. Crone, H.L. Owen
    UMAN, Manchester, United Kingdom
  • G.A. Krafft
    JLab, Newport News, Virginia, USA
  • G.A. Krafft, B. Terzić
    ODU, Norfolk, Virginia, USA
  • B.D. Muratori, P.H. Williams
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • B.D. Muratori, P.H. Williams
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  
  In­verse Comp­ton scat­ter­ing (ICS) holds the po­ten­tial for fu­ture high flux, nar­row band­width x-ray sources dri­ven by high qual­ity, high rep­e­ti­tion rate elec­tron beams. CBETA, the Cor­nell-BNL En­ergy re­cov­ery linac (ERL) Test Ac­cel­er­a­tor, is the world’s first su­per­con­duct­ing ra­diofre­quency multi-turn ERL, with a max­i­mum en­ergy of 150 MeV, ca­pa­ble of ICS pro­duc­tion of x-rays above 400 keV. We pre­sent an up­date on the by­pass de­sign and an­tic­i­pated pa­ra­me­ters of a com­pact ICS source at CBETA. X-ray pa­ra­me­ters from the CBETA ICS are com­pared to those of lead­ing syn­chro­tron ra­di­a­tion fa­cil­i­ties, demon­strat­ing that, above a few hun­dred keV, pho­ton beams pro­duced by ICS out­per­form those pro­duced by un­du­la­tors in term of flux and bril­liance.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB009  
About • paper received ※ 19 May 2021       paper accepted ※ 06 July 2021       issue date ※ 10 August 2021  
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THPAB035 Study of the Tolerances for Superconducting Undulators at the European XFEL undulator, FEL, electron, simulation 3819
 
  • B. Marchetti, S. Casalbuoni, V. Grattoni, S. Serkez
    EuXFEL, Schenefeld, Germany
  
  Eu­ro­pean XFEL is in­vest­ing in the de­vel­op­ment of su­per­con­duct­ing un­du­la­tors (SCUs) for fu­ture up­grade of its beam­lines SCUs made of NbTi, work­ing at 2K, with a pe­riod length of 15 mm and a vac­uum gap of 5 mm allow cov­er­ing a range be­tween 54 keV and 100 keV for 17.5 GeV elec­tron en­ergy. The ef­fect of me­chan­i­cal er­rors in the dis­tri­b­u­tion of K along the un­du­la­tors is more rel­e­vant for work­ing points at lower pho­ton en­ergy, which are ob­tained using a higher mag­netic field in the un­du­la­tor. In this ar­ti­cle we in­ves­ti­gate the ef­fect of error dis­tri­b­u­tion in the K-pa­ra­me­ter for a work­ing point at 50keV pho­ton en­ergy ob­tained in­ject­ing an elec­tron beam with 16.5 GeV en­ergy from the XFEL lin­ear ac­cel­er­a­tor in a un­du­la­tor line com­posed by SCUs with 1.58 T peak mag­netic field.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB035  
About • paper received ※ 12 May 2021       paper accepted ※ 05 July 2021       issue date ※ 18 August 2021  
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THPAB036 Superconducting Phase Shifter Design for the Afterburner at the European XFEL electron, FEL, undulator, operation 3823
 
  • V. Grattoni, J.E. Baader, S. Casalbuoni
    EuXFEL, Schenefeld, Germany
  
  At the Eu­ro­pean XFEL, a su­per­con­duct­ing af­ter­burner is under de­sign for the SASE2 hard X-ray beam­line. It will con­sist of 5 un­du­la­tor mod­ules. One mod­ule cor­re­sponds to two su­per­con­duct­ing un­du­la­tor (SCU) coils of 2 m length plus one phase shifter. Such an af­ter­burner will en­able pho­ton en­er­gies above 30 keV. Su­per­con­duct­ing (SC) phase shifters will be in­stalled in each un­du­la­tor mod­ule to keep the cor­rect phase delay be­tween the elec­tron beam and pho­ton beam. In this con­tri­bu­tion, we pre­sent the re­quired SC phase shifter pa­ra­me­ters to en­able op­er­a­tion in the elec­tron beam en­ergy range 11.5-17.5 GeV. We also an­a­lyze dif­fer­ent mag­netic de­signs sat­is­fy­ing the cal­cu­lated spec­i­fi­ca­tions.  
poster icon Poster THPAB036 [0.991 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB036  
About • paper received ※ 18 May 2021       paper accepted ※ 06 July 2021       issue date ※ 12 August 2021  
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THPAB040 A Phase Shifter for Inline Undulators at the Advanced Photon Source Upgrade Project undulator, electron, permanent-magnet, radiation 3830
 
  • E.R. Moog, R.J. Dejus, A.T. Donnelly, Y. Piao, M.F. Qian, 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.
Sev­eral un­du­la­tor lines for the Ad­vanced Pho­ton Source Up­grade (APS-U) will con­sist of two in­line un­du­la­tors. In order to keep the un­du­la­tors op­er­at­ing with op­ti­mal phas­ing over the full range of gaps, a phase shifter will be in­cluded be­tween the un­du­la­tors. A de­sign has been de­vel­oped for a phase shifter that will serve for a va­ri­ety of un­du­la­tor pe­riod lengths and gap ranges. The per­ma­nent-mag­net phase shifter will use SmCo mag­nets to re­duce the risk of ra­di­a­tion-in­duced de­mag­ne­ti­za­tion. The avail­able space be­tween the un­du­la­tors is tight, so mag­netic shields are placed be­tween the un­du­la­tors, the phase shifter, and the cor­rec­tor mag­net that is also lo­cated in the in­ter-un­du­la­tor space. While these shields guard against mag­netic cross-talk be­tween the de­vices as the un­du­la­tor and phase shifter gaps change, they do have an ef­fect on the end fields of the de­vices. These end-field ef­fects are ex­am­ined and rel­e­vant tol­er­ances are set and pre­sented. 		 
poster icon Poster THPAB040 [0.429 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB040  
About • paper received ※ 23 May 2021       paper accepted ※ 21 June 2021       issue date ※ 14 August 2021  
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THPAB041 Design of Photon Masks for the ILC Positron Source undulator, positron, site, target 3834
 
  • K.S. Alharbi, G.A. Moortgat-Pick, A. Ushakov
    University of Hamburg, Hamburg, Germany
  • K.S. Alharbi, S. Riemann
    DESY Zeuthen, Zeuthen, Germany
  • K.S. Alharbi, A.O. Alrashdi
    King Abdulaziz City for Science and Technology (KACST), The National Center for Accelerator Technology, Riyadh, Kingdom of Saudi Arabia
  • G.A. Moortgat-Pick
    DESY, Hamburg, Germany
  • P. Sievers
    CERN, Geneva, Switzerland
  
  A long su­per­con­duct­ing he­li­cal un­du­la­tor is planned as base­line to pro­duce po­lar­ized positrons at the In­ter­na­tional Lin­ear Col­lider (ILC). To pro­tect the un­du­la­tor walls from syn­chro­tron ra­di­a­tion, masks must be in­serted along the un­du­la­tor line. The power dis­tri­b­u­tion de­posited at these masks is stud­ied in order to de­sign the pho­ton masks.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB041  
About • paper received ※ 19 May 2021       paper accepted ※ 07 July 2021       issue date ※ 12 August 2021  
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THPAB045 Design of a Short Period Helical Superconducting Undulator undulator, FEL, electron, simulation 3844
 
  • A.G. Hinton
    STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
  • J. Boehm, L. Cooper, B. Green, T. Hayler, P. Jeffery, C.P. Macwaters
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • S. Milward
    DLS, Oxfordshire, United Kingdom
  • B.J.A. Shepherd
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • B.J.A. Shepherd
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  
  Su­per­con­duct­ing tech­nol­ogy pro­vides the pos­si­bil­ity to de­velop short pe­riod, small bore un­du­la­tors that can gen­er­ate much larger mag­netic fields than al­ter­na­tive tech­nolo­gies. This may allow an XFEL with op­ti­mised su­per­con­duct­ing un­du­la­tors to cover a broader range of wave­lengths than tra­di­tional un­du­la­tors. At STFC, we have un­der­taken work to de­sign and build a pro­to­type he­li­cal su­per­con­duct­ing un­du­la­tor (HSCU) mod­ule with pa­ra­me­ters suit­able for use on a fu­ture XFEL fa­cil­ity. This work in­cludes the de­sign of a full 2 m long un­du­la­tor mod­ule, in­clud­ing an un­du­la­tor with 13 mm pe­riod and 5 mm inner wind­ing di­am­e­ter, the sup­port­ing cryo­genic and vac­uum sys­tems re­quired for op­er­a­tion, and quadrupoles, phase shifters and cor­rec­tion mag­nets for use be­tween un­du­la­tor sec­tions. We pre­sent here the mag­netic and me­chan­i­cal de­sign of the HSCU. The choice of un­du­la­tor pa­ra­me­ters and their in­flu­ence on the de­sign is dis­cussed. A turn­around scheme to allow con­tin­u­ous wind­ing of the un­du­la­tor with­out the need for su­per­con­duct­ing joints is also pre­sented. Tech­niques for wind­ing the un­du­la­tor are cur­rently being in­ves­ti­gated and a short pro­to­type will soon be wound and tested.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB045  
About • paper received ※ 17 May 2021       paper accepted ※ 18 June 2021       issue date ※ 21 August 2021  
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THPAB050 Compact Hybrid Planar Permanent Magnet Undulator Design for the APS Upgrade undulator, ECR, lattice, permanent-magnet 3859
 
  • M. Abliz, M. Borland, J.H. Grimmer, J.S. Kerby, M. Ramanathan, A. Xiao
    ANL, Lemont, Illinois, USA
  
  We re­port on the suc­cess­ful de­sign of a com­pact 28-mm pe­riod hy­brid pla­nar per­ma­nent mag­net (HPPM) un­du­la­tor for the Ad­vanced Pho­ton Source Up­grade (APS-U) pro­ject. The de­sign pro­duces a peak field of 9750 G at a gap of 8.5 mm, with a pole width re­duced to 35 mm as com­pared to the pla­nar un­du­la­tors cur­rently in use at the Ad­vanced Pho­ton Source. The de­sign in­cludes a de­tailed in­ves­ti­ga­tion into the ori­gin of the HPPM un­du­la­tor de­mag­ne­ti­za­tion. We re­port on a find­ing of an op­ti­miza­tion method that re­duces the de­mag­ne­ti­za­tion field and in­creases the field at the gap cen­ter of the de­sign. It in­cludes an op­ti­miza­tion of the pole edges to in­crease the field and de­crease roll-off in the trans­verse di­rec­tion. Fur­ther de­sign op­ti­miza­tions in­clude analy­ses of the me­chan­i­cal as­sem­bly tol­er­ances and com­par­i­son with the orig­i­nal de­sign be­fore build­ing the de­vice. Beam physics analy­ses in­cluded kick-map analy­sis, dy­namic ac­cep­tance (DA), local mo­men­tum ac­cep­tance (LMA), and Tou­schek life­time of this de­sign were per­formed with the 42-pm lat­tice of the APS-U. De­tailed mag­netic de­sign, ef­fec­tive field, field roll-off, mag­netic force, and track­ing re­sults are re­ported.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB050  
About • paper received ※ 14 May 2021       paper accepted ※ 01 September 2021       issue date ※ 21 August 2021  
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THPAB051 Vertical Septum Magnet Design for the APS Upgrade septum, simulation, electron, magnet-design 3862
 
  • M. Abliz, M. Borland, H. Cease, G. Decker, A.K. Jain, M.S. Jaski, M. Kasa, J.S. Kerby, U. Wienands, A. Xiao
    ANL, Lemont, Illinois, USA
  • J.W. Amann
    SLAC, Menlo Park, California, USA
  • D.J. Harding
    Fermilab, Batavia, Illinois, USA
  
  The ver­ti­cal in­jec­tion scheme pro­posed for the APS Up­grade (APS-U) Pro­ject re­quires a chal­leng­ing sep­tum mag­net that must meet strin­gent beam physics, mag­netic field leak­age, and vac­uum re­quire­ments. The cur­rent it­er­a­tion of this mag­net de­sign in­cludes an en­larged stored-beam cham­ber aper­ture of 9 mm x 12 mm and a re­duc­tion of the sep­tum thick­ness to 1.5 mm. The en­larged aper­ture ac­com­mo­dates a non-evap­orable get­ter (NEG)-coated stored beam cham­ber to bet­ter achieve the re­quired vac­uum. A pro­to­type sep­tum mag­net has been built and mea­sure­ments con­firm the can­cel­la­tion of a peak leak­age field even though the value is six times larger than the de­sign. The leak­age field mea­sured at the up­stream (US) end can­cels the down­stream (DS) end as was ex­pected by de­sign. The mea­sured and sim­u­lated leak­age field and the stored beam tra­jec­to­ries are re­ported.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB051  
About • paper received ※ 14 May 2021       paper accepted ※ 01 September 2021       issue date ※ 27 August 2021  
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THPAB052 Insertion Devices at the MAX IV 3 GeV Ring wiggler, undulator, MMI, vacuum 3865
 
  • H. Tarawneh, M. Ebbeni, M. Gehlot, M. Holz
    MAX IV Laboratory, Lund University, Lund, Sweden
  
  Cur­rently, there are 8 In­ser­tion De­vices (ID) in­stalled and in op­er­a­tion and 2 new ones to be in­stalled end of 2021 at the MAX IV 3 GeV stor­age ring. In this paper, the first com­mis­sion­ing re­sults of the three newly in­stalled IDs in 2020 will be de­scribed. The new IDs are one APPLE II for Sof­t­i­MAX beam­line and two In-vac­uum Un­du­la­tors (IVU) for the Dan­MAX and CoSAXS beam­lines. The mit­i­ga­tion scheme adopted to re­duce un­du­la­tor-like ra­di­a­tion from BALDER in-vac­uum wig­gler will be dis­cussed. Two new IVUs with a pe­riod length of 17 mm and 18 mm for the For­MAX and Mi­cro­MAX beam­lines will be in­stalled dur­ing the win­ter shut­down of 2021-2022. Both IDs have 3 m lengths and a min­i­mum gap of 4 mm. In this paper, the mag­netic mea­sure­ment re­sults will be pre­sented in terms of the achieved field qual­ity and phase error.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB052  
About • paper received ※ 11 May 2021       paper accepted ※ 02 July 2021       issue date ※ 02 September 2021  
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THPAB053 Magnetic Field Calculation of Planar SCUs Using ANSYS Maxwell undulator, FEL, software, software-tool 3868
 
  • Y. Shiroyanagi, E.A. Anliker, Q.B. Hasse, H. Hu, Y. Ivanyushenkov, M. Kasa, I. Kesgin
    ANL, Lemont, Illinois, USA
  
  Funding: This work was supported by U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.
The Ad­vanced Pho­ton Source (APS) Up­grade in­cludes a 4.8-m-long su­per­con­duct­ing un­du­la­tor (SCU) cryo­stat con­tain­ing two 1.9-m-long, 16.5-mm-pe­riod pla­nar NbTi un­du­la­tor mag­nets. The mag­netic and me­chan­i­cal de­sign of this mag­net fol­lows the de­sign of the ex­ist­ing 1.1-m-long, 18-mm-pe­riod pla­nar SCU that is cur­rently in op­er­a­tion at the APS *. Al­though OPERA is a re­li­able stan­dard soft­ware tool for mag­netic field cal­cu­la­tions, ANSYS Maxwell 3D has the ad­van­tage of cal­cu­lat­ing a large and com­plex geom­e­try. In this paper, first, the mag­netic field map, in­clud­ing the peak field and end fields, is bench-marked against the mag­netic mea­sure­ment data of the ex­ist­ing pla­nar SCU18-1. Then, cor­rec­tor cur­rent op­ti­miza­tion is pre­sented for the 1.5-m-long, 21-mm-pe­riod pla­nar SCU. Fi­nally, a mag­netic field model of a full-scale, 1.9-m-long pla­nar SCU is pre­sented.
* Y. Ivanyushenkov et al., Phys. Rev. Accel. Beams 20, 100701 (2017).
 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB053  
About • paper received ※ 18 May 2021       paper accepted ※ 18 June 2021       issue date ※ 11 August 2021  
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THPAB054 Measurement Results of the First Scape Prototype undulator, insertion, superconducting-magnet, insertion-device 3872
 
  • M. Kasa, E.A. Anliker, Q.B. Hasse, Y. Ivanyushenkov, I. Kesgin, Y. Shiroyanagi, E. Trakhtenberg
    ANL, Lemont, Illinois, USA
  
  Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.
The SCAPE (Su­per­Con­duct­ing Ar­bi­trar­ily Po­lar­iz­ing Emit­ter) un­du­la­tor is under de­vel­op­ment at the Ad­vanced Pho­ton Source (APS) as a part of the APS up­grade. SCAPE is com­prised of four su­per­con­duct­ing mag­nets which are arranged to cre­ate an on-axis un­du­la­tor field that can be pla­nar, el­lip­ti­cal, or cir­cu­lar. As a first step to­wards de­vel­op­ing a full length de­vice, a 0.5-me­ter long pro­to­type was man­u­fac­tured and as­sem­bled for test­ing in a liq­uid he­lium bath cryo­stat. A de­scrip­tion of the me­chan­i­cal as­sem­bly and sub­se­quent mea­sure­ment re­sults of the first pro­to­type will be pre­sented in this paper. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB054  
About • paper received ※ 19 May 2021       paper accepted ※ 01 September 2021       issue date ※ 22 August 2021  
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THPAB061 Pulse-Burst CO2 Laser for High-Brilliance Compton Light Sources laser, electron, synchrotron, brightness 3890
 
  • I. Pogorelsky, M.N. Polyanskiy, T.V. Shaftan
    BNL, Upton, New York, USA
  
  Funding: U.S. Department of Energy under contract DE-SC0012704
We pro­pose a novel ar­chi­tec­ture for a mid-IR, high-rep­e­ti­tion, kilo­watt-class, CO2 laser sys­tem op­er­at­ing in a pulse-burst regime and its im­ple­men­ta­tion in In-verse Comp­ton Scat­ter­ing (ICS) sources of x-ray and gamma-ray ra­di­a­tion. Dif­fer­ent types of par­ti­cle ac­cel­er­a­tors are con­sid­ered for con­ver­sion to such ICS sources, in­clud­ing en­ergy re­cov­ery linacs and syn­chro­tron stor­age rings. The ex­pected ICS per­for­mance pa­ra­me­ters are com­pared with ear­lier pro­pos­als where CBETA and DAΦNE ac­cel­er­a­tors have been paired with near-IR, mode-locked solid-state lasers op­er­at­ing at a multi-mega­hertz rep­e­ti­tion rate. A con­sid­er­able in­crease in act­ing laser en­ergy at­tain­able in our CO2 laser-based scheme, com­bined with an order of mag­ni­tude higher num­ber of laser pho­tons per Joule of en­ergy al­lows main­tain­ing a sim­i­larly high av­er­age flux of pro­duced hard x-rays while the peak flux and bril­liance will be raised by three to four or­ders of mag­ni­tude com­pared to afore­men­tioned schemes based on near-IR lasers. 		 
poster icon Poster THPAB061 [1.082 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB061  
About • paper received ※ 12 May 2021       paper accepted ※ 21 June 2021       issue date ※ 29 August 2021  
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THPAB065 Experimental Verification of the Source of Excessive Helical SCU Heat Load at APS vacuum, radiation, synchrotron-radiation, synchrotron 3904
 
  • V. Sajaev, J.C. Dooling, K.C. Harkay
    ANL, Lemont, Illinois, USA
  
  Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Im­me­di­ately after the in­stal­la­tion of the He­li­cal su­per­con­duct­ing un­du­la­tor (HSCU) in the APS stor­age ring, higher than ex­pected heat­ing was ob­served in the cryo­genic cool­ing sys­tem. Steer­ing the elec­tron beam orbit in the up­stream di­pole re­duced the amount of syn­chro­tron ra­di­a­tion reach­ing into the HSCU and al­lowed the de­vice to prop­erly cool and op­er­ate. The sim­plest ex­pla­na­tion of the ex­ces­sive heat load was higher than ex­pected heat trans­fer from the vac­uum cham­ber to the mag­net coils. How­ever, mod­el­ing of the syn­chro­tron ra­di­a­tion in­ter­ac­tion with the HSCU vac­uum cham­ber showed that Comp­ton scat­ter­ing could also re­sult in syn­chro­tron ra­di­a­tion pen­e­trat­ing the vac­uum cham­ber and de­posit­ing en­ergy di­rectly into the HSCU coils**. In this paper, we pre­sent ex­per­i­men­tal ev­i­dence that the ex­ces­sive heat load of the HSCU coils is not caused by the heat trans­fer from the vac­uum cham­ber but re­sulted from the syn­chro­tron ra­di­a­tion pen­e­trat­ing the vac­uum cham­ber.
* M. Kasa et. al., Phys. Rev. AB, v. 23 050701 (2020)
** J. Dooling et. al., IPAC 2019 Proc., THPTS093 (2019) 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB065  
About • paper received ※ 12 May 2021       paper accepted ※ 02 September 2021       issue date ※ 16 August 2021  
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THPAB067 Simulation of the APS-U Orbit Motion Due to RF Noise simulation, synchrotron, resonance, cavity 3911
 
  • V. Sajaev
    ANL, Lemont, Illinois, USA
  
  Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
APS Up­grade stor­age ring will keep the same rf sys­tem that is presently used at APS. This rf sys­tem has am­pli­tude and phase noise dom­i­nated by the lines at 60, 180, and 360 Hz. APS presently op­er­ates with syn­chro­tron fre­quency close to 2 kHz, which is far away from the rf noise fre­quen­cies, and still the rf sys­tem noise con­tributes over 2 mi­crom­e­ters rms into the hor­i­zon­tal orbit noise due to beam en­ergy vari­a­tion. APS-U will op­er­ate with a bunch-length­en­ing cav­ity, which will lower the syn­chro­tron fre­quency down to about 200 Hz. This could po­ten­tially lead to large orbit noise and other neg­a­tive con­se­quences due to en­ergy vari­a­tion caused by the rf sys­tem noise. In this paper, we will pre­sent sim­u­la­tions of the rf noise-in­duced orbit mo­tion at APS and APS-U and de­fine the rf am­pli­tude and phase noise re­quire­ments that need to be achieved for APS-U op­er­a­tion. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB067  
About • paper received ※ 12 May 2021       paper accepted ※ 13 July 2021       issue date ※ 23 August 2021  
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THPAB078 SOLEIL Update Status controls, injection, synchrotron, vacuum 3945
 
  • L.S. Nadolski, G. Abeillé, Y.-M. Abiven, F. Bouvet, P. Brunelle, A. Buteau, N. Béchu, I. Chado, M.-E. Couprie, X. Delétoille, A. Gamelin, C. Herbeaux, N. Hubert, J.-F. Lamarre, V. Leroux, A. Lestrade, A. Loulergue, P. Marchand, O. Marcouillé, A. Nadji, R. Nagaoka, S. Pierre-Joseph Zéphir, F. Ribeiro, G. Schagene, K. Tavakoli, M.-A. Tordeux
    SOLEIL, Gif-sur-Yvette, France
  
  SOLEIL is both a syn­chro­tron light source and a re­search lab­o­ra­tory at the cut­ting edge of ex­per­i­men­tal tech­niques ded­i­cated to mat­ter analy­sis down to the atomic scale, as well as a ser­vice plat­form open to all sci­en­tific and in­dus­trial com­mu­ni­ties. This French 2.75 GeV third gen­er­a­tion syn­chro­tron light source pro­vides today ex­tremely sta­ble pho­ton beams to 29 beam­lines (BLs) com­ple­men­tary to ESRF. We re­port fa­cil­ity per­for­mance, on­go­ing pro­jects and re­cent major achieve­ments. Major R&D areas will also be dis­cussed, and progress to­wards a lat­tice base­line for mak­ing SOLEIL a dif­frac­tion lim­ited stor­age ring.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB078  
About • paper received ※ 22 May 2021       paper accepted ※ 12 July 2021       issue date ※ 22 August 2021  
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THPAB085 Status of Insertion Device Tuning for the APS Upgrade undulator, storage-ring, 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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THPAB142 Optical and Surface Characterization of Alkali-Antimonide Photocathodes cathode, electron, emittance, vacuum 4037
 
  • P. Saha, O. Chubenko, G.S. Gevorkyan, A.H. Kachwala, S.S. Karkare, C.J. Knill
    Arizona State University, Tempe, USA
  • E.J. Montgomery, S. Poddar
    Euclid Beamlabs, Bolingbrook, USA
  • H.A. Padmore
    LBNL, Berkeley, California, USA
  
  Al­kali-an­ti­monides, char­ac­ter­ized by high quan­tum ef­fi­ciency and low mean trans­verse en­ergy in vis­i­ble light, are ex­cel­lent elec­tron sources to drive x-ray free elec­tron lasers, elec­tron cool­ing and ul­tra­fast elec­tron dif­frac­tion ap­pli­ca­tions etc. Ex­ist­ing stud­ies of al­kali-an­ti­monides have fo­cused on quan­tum ef­fi­ciency and emit­tance, but in­for­ma­tion is lack­ing on the fun­da­men­tal as­pects of the elec­tronic struc­ture, such as the en­ergy gap of the semi­con­duc­tor and the den­sity of de­fects as well as the over­all nano-struc­ture of the ma­te­ri­als. We are, there­fore, con­duct­ing pho­to­con­duc­tiv­ity mea­sure­ments to mea­sure fun­da­men­tal semi­con­duc­tor prop­er­ties as well as using atomic force mi­cro­scope (AFM) and kelvin probe force mi­cro­scope (KPFM) to mea­sure the nanos­truc­ture vari­a­tions in struc­ture and sur­face po­ten­tial.  
poster icon Poster THPAB142 [1.211 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB142  
About • paper received ※ 16 May 2021       paper accepted ※ 14 July 2021       issue date ※ 13 August 2021  
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THPAB249 X-Ray Beam Position Monitor (XBPM) Calibration at NSRC Solaris controls, undulator, insertion, radiation 4292
 
  • M. Waniczek, A. Curcio, G.W. Kowalski, R. Panaś, A.I. Wawrzyniak
    NSRC SOLARIS, Kraków, Poland
  
  Dur­ing the in­stal­la­tion of Front-ends in sec­tions 4th (XMCD beam­line fron­tend) and 6th (PHE­LIX beam­line fron­tend) at Na­tional Syn­chro­tron Ra­di­a­tion Cen­tre So­laris (NSRC So­laris), two units (one for each front end) of X-ray Beam Po­si­tion Mon­i­tors (XBPM) have been in­stalled as a di­ag­nos­tic tool en­abling for mea­sure­ment of pho­ton beam po­si­tion. Hard­ware units of XBPM were man­u­fac­tured, de­liv­ered, and even­tu­ally in­stalled in So­laris by FMB Berlin. In order to get read­outs of beam po­si­tion from XBPM units, Lib­era Pho­ton 2016 con­troller has been used as a com­ple­men­tary elec­tronic de­vice. Since XBPM units are sup­posed to be used along with the in­ser­tion de­vice, an on-site Lib­era cal­i­bra­tion was nec­es­sary. Lib­era’s cal­i­bra­tion re­quired few it­er­a­tions of scans in­volv­ing gap and phase move­ment of in­ser­tion de­vices at the 4th and 6th sec­tions of the So­laris ring. The main focus was put on the de­riva­tion of Kx, and Ky co­ef­fi­cients. The con­tent of this doc­u­ment de­scribes step by step the pro­ce­dure of Lib­era’s Kx, Ky co­ef­fi­cients value de­riva­tion at NSRC So­laris.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB249  
About • paper received ※ 19 May 2021       paper accepted ※ 17 July 2021       issue date ※ 13 August 2021  
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THPAB270 Pair Spectrometer for FACET-II electron, positron, scattering, detector 4336
 
  • B. Naranjo, G. Andonian, A. Fukasawa, N. Majernik, M.H. Oruganti, J.B. Rosenzweig, Y. Sakai, O. Williams, M. Yadav
    UCLA, Los Angeles, California, USA
  • N. Cavanagh, G. Sarri
    Queen’s University of Belfast, Belfast, Northern Ireland, United Kingdom
  • A. Di Piazza, C.H. Keitel
    MPI-K, Heidelberg, Germany
  • E. Gerstmayr, S. Meuren, D.A. Reis, D.W. Storey, V. Yakimenko
    SLAC, Menlo Park, California, USA
  • R. Holtzapple
    CalPoly, San Luis Obispo, California, USA
  • C. Nielsen
    AU, Aarhus, Denmark
  
  Funding: DARPA GRIT Contract 20204571, DOE HEP Grant DE-SC0009914
We pre­sent the de­sign of a pair spec­trom­e­ter for use at FACET-II, where there is a need for spec­troscopy of pho­tons hav­ing en­er­gies up to 10 GeV. In­com­ing gam­mas are con­verted to high-en­ergy positron-elec­tron pairs, which are then sub­se­quently an­a­lyzed in a di­pole mag­net. These charged par­ti­cles are then recorded in ar­rays of acrylic Cherenkov coun­ters, which are sig­nif­i­cantly less sen­si­tive to back­ground x-rays than scin­til­la­tor coun­ters in this case. To re­con­struct en­er­gies of sin­gle high-en­ergy pho­tons, the spec­trom­e­ter has a sen­si­tiv­ity to sin­gle positron-elec­tron pairs. Even in this sin­gle-pho­ton limit, there is al­ways some low-en­ergy con­tin­uum pre­sent, so spec­tral de­con­vo­lu­tion is not triv­ial, for which we demon­strate a max­i­mum like­li­hood re­con­struc­tion. Fi­nally, end-to-end sim­u­la­tions of ex­per­i­men­tal sce­nar­ios, to­gether with an­tic­i­pated back­grounds, are pre­sented. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB270  
About • paper received ※ 20 May 2021       paper accepted ※ 28 July 2021       issue date ※ 18 August 2021  
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THPAB273 Spectral Reconstruction for FACET-II Compton Spectrometer network, electron, site, positron 4346
 
  • Y. Zhuang, B. Naranjo, J.B. Rosenzweig, M. Yadav
    UCLA, Los Angeles, USA
  
  Funding: This work was supported by DOE Contract DE-SC0009914, NSF Grant No. PHY-1549132, and DARPA GRIT Contract 20204571.
The Comp­ton spec­trom­e­ter under de­vel­op­ment at UCLA for FACET-II is a ver­sa­tile tool to an­a­lyze gamma-ray spec­tra in a sin­gle shot, in which the en­ergy and an­gu­lar po­si­tion of the in­com­ing pho­tons are recorded by ob­serv­ing the mo­menta and po­si­tion of Comp­ton scat­tered elec­trons. We pre­sent meth­ods to re­con­struct the pri­mary spec­trum from these data via ma­chine learn­ing and the EM Al­go­rithm. A multi-layer fully con­nected neural net­work is used to per­form the re­gres­sion task of re­con­struct­ing both the dou­ble-dif­fer­en­tial spec­trum and the pho­ton en­ergy spec­trum in­ci­dent with zero an­gu­lar off­set. We pre­sent the ex­pected per­for­mance of these tech­niques, con­cen­trat­ing on the achiev­able en­ergy res­o­lu­tion. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB273  
About • paper received ※ 20 May 2021       paper accepted ※ 28 July 2021       issue date ※ 16 August 2021  
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THPAB276 X-Ray Double Slit Interferometer Progress at CLS synchrotron, simulation, storage-ring, emittance 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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THPAB291 DYVACS (DYnamic VACuum Simulation) Code: Gas Density Profiles in Presence of Electron Cloud in the LHC electron, proton, vacuum, injection 4373
 
  • S. Bilgen, B. Mercier, G. Sattonnay
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • V. Baglin
    CERN, Meyrin, Switzerland
  
  The com­pu­ta­tion of resid­ual gas den­sity pro­files in par­ti­cle ac­cel­er­a­tors is an es­sen­tial task to op­ti­mize beam pipes and vac­uum sys­tem de­sign. In a hadron col­lider such as the LHC, the beam in­duces dy­namic ef­fects due to ion, elec­tron, and pho­ton-stim­u­lated gas des­orp­tion. The well-known VASCO* code de­vel­oped at CERN in 2004 is al­ready used to es­ti­mate vac­uum sta­bil­ity and den­sity pro­files in steady-state con­di­tions. Nev­er­the­less, some phe­nom­ena are not taken into ac­count such as the ion­iza­tion of resid­ual gas by the elec­tron clouds and the evo­lu­tion of the elec­tronic den­sity re­lated to the elec­tron cloud build-up. There­fore, we pro­pose an up­grade of this code by in­tro­duc­ing elec­tron cloud maps** to es­ti­mate the elec­tron den­sity and the ion­iza­tion of gas by elec­trons lead­ing to an in­crease of in­duced des­orp­tion. The pres­sure evo­lu­tion com­puted with DY­VACS re­pro­duces with good ac­cu­racy the ex­per­i­men­tal pres­sure recorded in the VPS beam pipes sec­tor*** of the LHC from the pro­ton beam in­jec­tion to the sta­ble beam pe­riod. Ad­di­tion­ally, DY­VACS can also be used as a pre­dic­tive tool to com­pute the pres­sure evo­lu­tion in the beam pipes for Fu­ture Cir­cu­lar Col­lid­ers (FCC-hh or -ee).
* A. Rossi, Tech. Report, LHC Project Note 341
** T. Demma et al Phys. Rev. Acceler. and Beams 10, 114401 (2007)
*** B. Henrist et al, Proc. IPAC2014, Dresden
 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB291  
About • paper received ※ 19 May 2021       paper accepted ※ 02 August 2021       issue date ※ 31 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)