Keyword: feedback
Paper Title Other Keywords Page
MOPOST053 Transverse Resonance Islands Buckets at SPEAR3 kicker, lattice, resonance, experiment 203
 
  • J. Kim, J.A. Safranek, K. Tian
    SLAC, Menlo Park, California, USA
  
  We pre­sent pop­u­lat­ing bunches into the trans­verse res­o­nance is­lands buck­ets (TRIBs) on SPEAR3. As one of op­er­a­tion modes for the tim­ing-mode or pro­vid­ing sep­a­rated bunches in trans­verse di­rec­tion, we are ex­plor­ing TRIBs on SPEAR3. Ex­pe­ri­ence and analy­sis on ap­ply­ing kicks mul­ti­ple times using the bunch-by-bunch feed­back kicker to move bunches into the TRIBs is de­scribed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST053  
About • Received ※ 06 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT002 Improvements on Sirius Beam Stability controls, operation, network, experiment 226
 
  • S.R. Marques, M.B. Alves, F.C. Arroyo, M.P. Calcanha, H.F. Canova, B.E. Limeira, L. Liu, R.T. Neuenschwander, A.G.C. Pereira, D.O. Tavares, F.H. de Sá
    LNLS, Campinas, Brazil
  • G.O. Brunheira, A.C.T. Cardoso, R.B. Cardoso, R. Junqueira Leão, L.R. Leão, P.H.S. Martins, Moreira, S.S. Moreira, R. Oliveira Neto, M.G. Siqueira
    CNPEM, Campinas, SP, Brazil
  
  Sir­ius is a Syn­chro­tron Light Source based on a 3 GeV elec­tron stor­age ring with 518 me­ters cir­cum­fer­ence and 250 pm.​rad emit­tance. The fa­cil­ity is built and op­er­ated by the Brazil­ian Syn­chro­tron Light Lab­o­ra­tory (LNLS), lo­cated in the CNPEM cam­pus, in Camp­inas. A beam sta­bil­ity task force was re­cently cre­ated to iden­tify and mit­i­gate the orbit dis­tur­bances at var­i­ous time scales. This work pre­sents stud­ies re­gard­ing ground mo­tion (land sub­si­dence caused by ground­wa­ter ex­trac­tion), im­prove­ments in the tem­per­a­ture con­trol of the stor­age ring (SR) tun­nel air con­di­tion­ing (AC) sys­tem, vi­bra­tion mea­sure­ments in ac­cel­er­a­tor com­po­nents and the ef­forts con­cern­ing the re­duc­tion of the power sup­plies’ rip­ple. The fast orbit feed­back im­ple­men­ta­tion and other fu­ture per­spec­tives will also be dis­cussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT002  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT003 Studying Instabilities in the Canadian Light Source Storage Ring Using the Transverse Feedback System storage-ring, insertion, insertion-device, damping 230
 
  • S.J. Martens
    University of Saskatchewan, Saskatoon, Canada
  • D. Bertwistle, M.J. Boland
    CLS, Saskatoon, Saskatchewan, Canada
  • P. Hartmann
    DELTA, Dortmund, Germany
  
  The Trans­verse Feed­back sys­tem at the Cana­dian Light Source can iden­tify, cat­e­go­rize, and mit­i­gate against pe­ri­odic in­sta­bil­i­ties that arise in the stor­age ring beam. By quickly open­ing and clos­ing the feed­back loop, pre­vi­ously mit­i­gated in­sta­bil­i­ties will be al­lowed to grow briefly be­fore being damped by the sys­tem. The re­sult­ing growth in the beam os­cil­la­tion am­pli­tude curve can be an­a­lyzed to de­ter­mine growth/damp rates and modes of the cou­pled bunch os­cil­la­tions. Fur­ther mea­sure­ments can be col­lected via ac­tive ex­cite­ment of modes rather than pas­sive growth. These Grow/damp and Ex­cite/Damp curves have been col­lected and an­a­lyzed for var­i­ous stor­age ring beam prop­er­ties, in­clud­ing beam en­ergy, ma­chine chro­matic­ity, and in-vac­uum in­ser­tion de­vice gap widths.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT003  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT016 Update of the Bunch Arrival Time Monitor at ELBE laser, electron, controls, pick-up 260
 
  • M. Kuntzsch, A. Maalberg, A. Schwarz, K. Zenker
    HZDR, Dresden, Germany
  • M.K. Czwalinna, J. Kral
    DESY, Hamburg, Germany
  
  The bunch ar­rival time mon­i­tor (BAM) at the ra­di­a­tion source ELBE has been up­graded twofold. In order to achieve a higher pre­ci­sion a new fron­tend has been de­signed, based on a de­vel­op­ment by DESY, that uses state of the art 50 GHz elec­tro-op­ti­cal mod­u­la­tors (EOMs). The fron­tend al­lows for ther­mal con­trol of crit­i­cal com­po­nents and mon­i­tor­ing of sys­tem pa­ra­me­ters. The mod­u­lated EOM sig­nals and mon­i­tor­ing data are dis­trib­uted to a new read­out elec­tronic. The new Mi­croTCA-based re­ceiveris based on a ded­i­cated FMC card de­vel­oped at DESY that is in­stalled on an FMC25 car­rier board. The ar­rival time is cal­cu­lated on a FPGA with low la­tency and can be used for ma­chine di­ag­nos­tic. The code has been adapted to en­able the pro­cess­ing of a data stream of the con­tin­u­ous train of elec­tron bunches, al­low­ing for the im­ple­men­ta­tion of a cw beam based feed­back in a next step. The con­tri­bu­tion will de­scribe the BAM setup as well as the per­for­mance mea­sured at the ELBE ac­cel­er­a­tor.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT016  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT038 Development of Button BPM Electronics for the Bunch by Bunch Feedback System of 4GSR electron, electronics, storage-ring, booster 332
 
  • S.W. Jang
    KUS, Sejong, Republic of Korea
  
  With the ad­vent of the fourth-gen­er­a­tion stor­age ring, the size of the ver­ti­cal emit­tance of the elec­tron beam is ex­pected to be about 100 times smaller than that of the ex­ist­ing gen­er­a­tion. In line with the de­vel­op­ment of ac­cel­er­a­tor per­for­mance, the res­o­lu­tion of the beam po­si­tion mon­i­tor(BPM) should also be fur­ther im­proved, and it can be pro­vide a more sta­ble and uni­form beam to end sta­tion users through im­proved bunch by bunch(BbB) feed­back sys­tem com­pared to a sys­tem called turn by turn or fast feed­back. A de­vel­oped BPM elec­tron­ics for BbB feed­back will be in­stalled in Bessy II booster ring at HZB Re­search In­sti­tute in Ger­many. BbB feed­back BPM elec­tron­ics with an im­proved three but­ton BPMs will be used to mea­sure beam po­si­tion res­o­lu­tion and cal­cu­late an in­for­ma­tion for BbB feed­back and then it will apply to the BbB feed­back sys­tem. In this pro­ceed­ing, we will de­scribe the de­vel­op­ment of an up­graded beam po­si­tion mon­i­tor and BPM elec­tron­ics for BbB feed­back.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT038  
About • Received ※ 08 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 02 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUOXGD3 6D Phase Space Diagnostics Based on Adaptively Tuned Physics-Informed Generative Convolutional Neural Networks controls, solenoid, network, diagnostics 776
 
  • A. Scheinker
    LANL, Los Alamos, New Mexico, USA
  • F.W. Cropp V
    UCLA, Los Angeles, USA
  • D. Filippetto
    LBNL, Berkeley, California, USA
  
  Funding: US Department of Energy, DOE Office of Science Graduate Student Research (SCGSR) contract numbers 89233218CNA000001 and DE-AC02-05CH11231 and by the NSF under Grant No. PHY-1549132.
A physics-in­formed gen­er­a­tive con­vo­lu­tional neural net­work (CNN)-based 6D phase space di­ag­nos­tic is pre­sented which gen­er­ates all 15 unique 2D pro­jec­tions (x,y), (x,y’),…, (z,E) of a charged par­ti­cle beam’s 6D phase space (x,y,z,x’,y’,E)*. The CNN is trained by su­per­vised learn­ing over a wide range of input beam dis­tri­b­u­tions, ac­cel­er­a­tor pa­ra­me­ters, and the as­so­ci­ated 6D beam phase spaces at mul­ti­ple ac­cel­er­a­tor lo­ca­tions. The CNN is ap­plied in an un-su­per­vised adap­tive man­ner with­out knowl­edge of the input beam dis­tri­b­u­tion or ac­cel­er­a­tor pa­ra­me­ters and is ro­bust to their un­known time vari­a­tion. Adap­tive feed­back au­to­mat­i­cally tunes the low-di­men­sional la­tent space of the en­coder-de­coder CNN to pre­dict the 6D phase space based only on 2D (z,E) lon­gi­tu­di­nal phase space mea­sure­ments from a de­vice such as a trans­verse de­flect­ing RF cav­ity (TCAV). This method has the po­ten­tial to pro­vide di­ag­nos­tics be­yond the ex­ist­ing state of the art at many ac­cel­er­a­tor fa­cil­i­ties. Stud­ies are pre­sented for two very dif­fer­ent ac­cel­er­a­tors: the 5-me­ter-long ul­tra-fast elec­tron dif­frac­tion (UED) HiRES com­pact ac­cel­er­a­tor at LBNL and the kilo­me­ter long plasma wake­field ac­cel­er­a­tor FACET-II at SLAC.
*A. Scheinker. "Adaptive machine learning for time-varying systems: low dimensional latent space tuning." Journal of Instrumentation 16.10, 2021: P10008. https://doi.org/10.1088/1748-0221/16/10/P10008 		 
slides icon Slides TUOXGD3 [3.112 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOXGD3  
About • Received ※ 21 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST007 New Generation of Very Low Noise Beam Position Measurement System for the LHC Transverse Feedback pick-up, controls, operation, injection 849
 
  • D. Valuch
    CERN, Meyrin, Switzerland
  • V. Stopjakova
    Slovak University of Technology (STU), Faculty of Electrical Engineering and Information Technology, Bratislava, Slovak Republic
  
  Re­cent stud­ies showed that the trans­verse feed­back sys­tem noise floor in the Large Hadron Col­lider (LHC) must be re­duced by at least fac­tor of two in order to op­er­ate the ma­chine with large beam-beam tune shift as fore­seen in the High Lu­mi­nos­ity (HL) LHC. Also, the fu­ture feed­back sys­tem fore­seen to sup­press the LHC Crab Cav­ity noise re­lies on im­proved noise per­for­mance of the beam po­si­tion mea­sure­ment sys­tem. An up­grade pro­gram was launched to lower the LHC trans­verse feed­back sys­tem noise floor dur­ing the LHC Long Shut­down II. A new gen­er­a­tion, very low noise beam po­si­tion mea­sure­ment mod­ule was de­vel­oped and tested with beam. In­no­v­a­tive meth­ods in the RF re­ceiver, dig­i­tal sig­nal pro­cess­ing, thor­ough op­ti­miza­tion of every el­e­ment in the sig­nal chain from pickup to the kick­ers al­lowed to achieve a sig­nif­i­cant re­duc­tion of the sys­tem noise floor. This un­prece­dented noise per­for­mance opens also new pos­si­bil­i­ties for aux­il­iary in­stru­ments, using the po­si­tion data from the trans­verse feed­back. The paper pre­sents the new sys­tem, no­table im­ple­men­ta­tion de­tails and mea­sured per­for­mance.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST007  
About • Received ※ 18 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST011 Simulation Studies of Intra-Train, Bunch-by-Bunch Feedback Systems at the International Linear Collider luminosity, collider, ground-motion, linear-collider 861
 
  • R.L. Ramjiawan, D.R. Bett, P. Burrows, C. Perry
    JAI, Oxford, United Kingdom
  • D.R. Bett
    CERN, Meyrin, Switzerland
  • R.M. Bodenstein
    JLab, Newport News, Virginia, USA
  • G.B. Christian
    DLS, Oxfordshire, United Kingdom
  
  The In­ter­na­tional Lin­ear Col­lider (ILC) is a pro­posed elec­tron-positron col­lider tar­get­ing col­li­sion en­er­gies from 250 GeV to 1 TeV. With de­sign lu­mi­nosi­ties of order 1034 cm2s-1, a beam-based, in­tra-train feed­back sys­tem would be re­quired near the In­ter­ac­tion Point (IP) to pro­vide nanome­tre-level sta­bil­i­sa­tion of the beam over­lap in the col­li­sions. Here we pre­sent re­sults from beam-track­ing sim­u­la­tions of the 500 GeV ILC, in­clud­ing the im­pact of beam-tra­jec­tory im­per­fec­tions on the lu­mi­nos­ity, and the ca­pa­bil­ity of the IP feed­back sys­tem to com­pen­sate for them. Ef­fects in­ves­ti­gated in­clude the po­si­tion jit­ter in­tro­duced by the damp­ing ring ex­trac­tion kicker, short-range and long-range wake­fields, and ground mo­tion. The feed­back sys­tem was shown to be able to cor­rect for beam-beam off­sets of up to 200 nm and sta­bilise the col­li­sion over­lap to the nanome­tre level, within a few bunch cross­ings.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST011  
About • Received ※ 03 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST023 The CERN SPS Low level RF: The Cavity-Controller cavity, controls, LLRF, proton 903
 
  • G. Hagmann, P. Baudrenghien, J. Egli, A. Spierer, M. Sumiński, T. Włostowski
    CERN, Meyrin, Switzerland
  
  This paper is the sec­ond of a se­ries of three on the Super Pro­ton Syn­chro­tron (SPS) Low Level RF (LLRF) up­grade. It cov­ers the 200MHz Cav­ity-Con­troller part, that is re­spon­si­ble for the reg­u­la­tion of the ac­cel­er­at­ing field in a sin­gle SPS cav­ity. When the SPS is used as Large Hadron Col­lider (LHC) pro­ton in­jec­tor, the issue is the high beam load­ing that must be com­pen­sated to guar­an­tee lon­gi­tu­di­nal sta­bil­ity and con­stant pa­ra­me­ters over the bunch train. That calls for strong One-Turn Delay Feed­back (OTFB) and Feed-For­ward (FFWD). The SPS is also ac­cel­er­at­ing Lead ions (Pb). There the issue is Fre­quency-Mod­u­la­tion (FM) and Am­pli­tude-Mod­u­la­tion (AM) over the turn (so called Fixed Fre­quency Ac­cel­er­a­tion - FFA) plus RF gym­nas­tics for the new ions slip-stack­ing. The paper re­views the func­tional re­quire­ments, pre­sents the block di­a­gram, then gives de­tails on the sig­nal pro­cess­ing, firmware and hard­ware. Fi­nally re­sults from the first year of beam com­mis­sion­ing are pre­sented (2021).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST023  
About • Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST024 A New Beam Loading Compensation and Blowup Control System Using Multi-Harmonic Digital Feedback Loops in the CERN Proton Synchrotron Booster cavity, controls, LLRF, operation 907
 
  • D. Barrientos, S.C.P. Albright, M.E. Angoletta, A. Findlay, M. Jaussi, J.C. Molendijk
    CERN, Meyrin, Switzerland
  
  As part of the LHC In­jec­tors Up­grade, the CERN Pro­ton Syn­chro­tron Booster (PSB) has been up­graded with new wide-band Finemet cav­i­ties and a ren­o­vated Low-Level Radio Fre­quency sys­tem with dig­i­tal cav­ity con­trollers im­ple­mented in FPGAs. Each con­troller syn­chro­nously re­ceives the com­puted rev­o­lu­tion fre­quency, used to gen­er­ate 16 har­monic ref­er­ences. These are then used to IQ de­mod­u­late the volt­age gap and mod­u­late the 16 RF drive sig­nals each con­trolled through a Carte­sian feed­back loop (with in­di­vid­ual volt­age and phase con­trol). The sum of these dig­i­tal drive sig­nals is then sent to the cav­i­ties. In ad­di­tion, a con­fig­urable blow-up sys­tem pro­vid­ing a si­nu­soidal or cus­tom noise pat­tern can be used to ex­cite the beam. An em­bed­ded net­work an­a­lyzer al­lows study­ing the sta­bil­ity of the feed­back loops of the in­di­vid­ual har­mon­ics. The 16 har­monic feed­back loops have been suc­cess­fully op­er­ated dur­ing 2021, al­low­ing to re­duce the beam in­duced volt­age and con­trol the lon­gi­tu­di­nal emit­tance of the beam. In this paper we pre­sent the sys­tem ar­chi­tec­ture as well as the per­for­mance of the com­plete cav­ity con­troller dur­ing op­er­a­tion in the PSB.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST024  
About • Received ※ 23 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST037 Reconstruction of Transverse Phase Space From Transverse Feedback Data for Real Time Extraction of Vital LHC Machine Parameters pick-up, real-time, injection, betatron 937
 
  • G. Kotzian, M.E. Soderen, P.S. Solvang, D. Valuch
    CERN, Meyrin, Switzerland
  • V. Stopjakova
    Slovak University of Technology (STU), Faculty of Electrical Engineering and Information Technology, Bratislava, Slovak Republic
  
  The LHC trans­verse feed­back sys­tem (ADT) pro­vides bunch by bunch, turn by turn, nor­mal­ized and dig­i­tized beam po­si­tion sig­nals from four pick-ups per plane and for each beam. To­gether with al­ready ex­ist­ing pow­er­ful com­puter-based ob­ser­va­tion sys­tems, this data can be used to re­con­struct in real-time the trans­verse phase space co­or­di­nates of the cen­tre-of-charges, for each in­di­vid­ual bunch. Such in­for­ma­tion is ex­tremely valu­able for ma­chine op­er­a­tion, or trans­verse in­sta­bil­ity di­ag­nos­tics. This paper aims on dis­cussing and eval­u­at­ing meth­ods of com­bin­ing four po­si­tion sig­nals for such analy­sis in the pres­ence of noise and with ac­tive trans­verse feed­back. Com­par­isons are made based on the ex­trac­tion of vital pa­ra­me­ters like the frac­tional tune or trans­verse ac­tiv­ity. An­a­lyt­i­cal and nu­mer­i­cal re­sults are fur­ther bench­marked against real beam data.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST037  
About • Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST055 Toward Machine Learning-Based Adaptive Control and Global Feedback for Compact Accelerators controls, diagnostics, electron, quadrupole 991
 
  • F.W. Cropp V, P. Musumeci
    UCLA, Los Angeles, USA
  • D. Filippetto, A. Gilardi, S. Paiagua, D. Wang
    LBNL, Berkeley, California, USA
  • A. Scheinker
    LANL, Los Alamos, New Mexico, USA
  
  Funding: This work was supported by the DOE Office of Science Graduate Student Research (SCGSR) program, by the DOE Office of Basic Energy Sciences under Contract No. DE-AC02-05CH11231, … continued
The HiRES beam­line at Lawrence Berke­ley Na­tional Lab­o­ra­tory (USA) is a state-of-the-art com­pact ac­cel­er­a­tor pro­vid­ing ul­tra­fast rel­a­tivis­tic elec­tron pulses at MHz rep­e­ti­tion rates, for ap­pli­ca­tions in ul­tra­fast sci­ence and for par­ti­cle ac­cel­er­a­tor sci­ence and tech­nol­ogy R&D. Using HiRES as test­bed, we seek to apply re­cent de­vel­op­ments in ma­chine learn­ing and com­pu­ta­tional tech­niques for ma­chine-learn­ing-based adap­tive con­trol, and even­tu­ally, a full con­trol sys­tem based on global feed­back. The ul­ti­mate goal is to demon­strate the ben­e­fits of such a suite of con­trols to UED, in­clud­ing in­creased tem­po­ral and spa­tial res­o­lu­tion. Con­crete steps to­ward these goals are pre­sented, in­clud­ing au­to­matic, model-in­de­pen­dent tun­ing for ac­cel­er­a­tors, and en­ergy vir­tual di­ag­nos­tics with di­rect ap­pli­ca­tion to im­prov­ing UED tem­po­ral res­o­lu­tion.
… [continued from below] by the DOE Office of Science, Office of High Energy Physics under contract number 89233218CNA000001 and DE-AC02-05CH11231 and by the NSF under Grant No. PHY-1549132. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST055  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT026 Design and Status of Fast Orbit Feedback System at SOLARIS controls, storage-ring, power-supply, hardware 1059
 
  • G.W. Kowalski, K. Gula, R. Panaś, A.I. Wawrzyniak, J.J. Wiechecki
    NSRC SOLARIS, Kraków, Poland
  
  SO­LARIS stor­age ring has been built with basic set of di­ag­nos­tic and feed­back sys­tems. FOFB sys­tem, as much more ad­vanced and not as crit­i­cal for startup was en­vi­sioned as later ad­di­tion to the de­sign. Now, we are in the process of im­ple­ment­ing this ad­di­tion. The sys­tem’s work­horse is In­stru­men­ta­tion Tech­nolo­gies Lib­era Bril­liance+ with its Fast Ac­qui­si­tion data path and cus­tomiz­able FPGA mod­ules. Feed­back al­go­rithm run­ning in hard­ware pro­vides fast cal­cu­la­tions and di­rect com­mu­ni­ca­tion with fast power sup­plies. The hard­ware in­stal­la­tion is al­most fin­ished with con­fig­u­ra­tion and soft­ware works run­ning in par­al­lel. First mea­sure­ments of re­sponse ma­trix and proof-of-con­cept tests were per­formed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT026  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT066 KEK LUCX Facility Laser-to-RF&RF-to-RF Stability Study and Optimization laser, LLRF, gun, timing 1167
 
  • K. Popov
    Sokendai, Ibaraki, Japan
  • A. Aryshev, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  
  KEK LUCX fa­cil­ity* is a lin­ear ac­cel­er­a­tor de­voted to the beam in­stru­men­ta­tion R&Ds for pre­sent and fu­ture ac­cel­er­a­tor sys­tems and col­lid­ers in­clud­ing ILC. Ac­cord­ing to the ILC TDR**, it is nec­es­sary to achieve RF-gun Laser-to-RF&RF-to-RF phase sta­bil­ity of 0.35°(RMS) and am­pli­tude sta­bil­ity of 0.07%(RMS) with im­ple­men­ta­tion of the Dig­i­tal LLRF feed­back based on com­mer­cially avail­able FPGA board and dig­i­tal trig­ger sys­tem. As the first step to achieve ILC sta­bil­ity level at KEK-LUCX fa­cil­ity, pre­sent Laser-to-RF&RF-to-RF phase and am­pli­tude jit­ters were mea­sured using time- and fre­quency-do­main tech­niques. After that, jit­ter in­flu­ence on beam pa­ra­me­ters after RF-gun and main so­le­noid mag­net was sim­u­lated with ASTRA track­ing code*** and re­sults were cross-checked dur­ing LUCX fa­cil­ity beam op­er­a­tion. Fi­nally, sta­ble dig­i­tal trig­ger sys­tem and dig­i­tal LLRF feed­back based on SINAP EVG&EVR and Red­Pi­taya SIG­NAL­lab-250 mod­ules were im­ple­mented. This re­port demon­strates the re­sults of Laser-to-RF&RF-to-RF phase and am­pli­tude jit­ter mea­sure­ments cross-checked with ASTRA sim­u­la­tion and real beam pa­ra­me­ters mea­sure­ments be­fore and after LUCX fa­cil­ity sta­bi­liza­tion.
References
*A. Aryshev et al., Appl. Phys. Lett. 111, 033508 (2017).
**International Linear Collider Reference Design Report, ILC-REPORT-2007-001, 2007.
***https://www.desy.de/~mpyflo/
 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT066  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS035 Emittance Feedback for the Diamond-II Storage Ring Using Resonant Excitation emittance, impedance, storage-ring, synchrotron 1498
 
  • S. Preston, T. Olsson, B. Singh
    DLS, Oxfordshire, United Kingdom
  
  In the Di­a­mond Light Source stor­age ring, the ver­ti­cal emit­tance is kept at 8 pm rad dur­ing op­er­a­tion to main­tain the source bright­ness for the users. This is achieved by a feed­back which mod­i­fies the skew quadru­pole strengths, but has dis­ad­van­tages such as the in­tro­duc­tion of be­ta­tron cou­pling and ver­ti­cal dis­per­sion. For the pro­posed Di­a­mond-II up­grade, the stor­age ring will have a much smaller hor­i­zon­tal emit­tance, mean­ing a sig­nif­i­cantly larger cou­pling would be re­quired to reach the tar­get ver­ti­cal emit­tance, neg­a­tively af­fect­ing the off-axis in­jec­tion process. To solve this prob­lem, a feed­back using the trans­verse multi­bunch feed­back striplines to drive the beam at a syn­chro­tron side­band is planned. By dri­ving the beam res­o­nantly in this way, the emit­tance can be in­creased with­out mod­i­fi­ca­tion of the op­tics. This paper de­scribes sim­u­la­tions of the ef­fects of lin­ear and non-lin­ear op­tics on the ex­ci­ta­tion as well as the im­pact of the ma­chine im­ped­ance for the Di­a­mond-II stor­age ring.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS035  
About • Received ※ 19 May 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK046 Improved Longitudinal Performance of the LHC Beam in the CERN PS extraction, emittance, cavity, flattop 2165
 
  • H. Damerau, V.D. Desquiens, A. Huschauer, A. Jibar, A. Lasheen, B. Mikulec, M. Morvillo, C. Rossi, B.J. Woolley
    CERN, Meyrin, Switzerland
  
  At the end of the 2018 run the in­ten­sity tar­get for the High-Lu­mi­nos­ity LHC (HL-LHC) had just been reached at ex­trac­tion from the Pro­ton Syn­chro­tron (PS). In the frame­work of the LHC In­jec­tors Up­grade (LIU) pro­ject ad­di­tional RF im­prove­ments have been im­ple­mented dur­ing the 2019/2020 long shut­down (LS2), mainly im­pact­ing the im­ped­ance of the 10 MHz, 40 MHz, and 80 MHz RF sys­tems. With the up­graded in­jec­tion en­ergy of 2 GeV (ki­netic), also the in­ter­me­di­ate plateau en­ergy for RF ma­nip­u­la­tions has been in­creased. Fol­low­ing a cam­paign of beam stud­ies through­out the 2021 run, a bunch in­ten­sity of up to 2.9·1011 p/b in trains of 72 bunches is achieved with the re­quired lon­gi­tu­di­nal beam qual­ity, sur­pass­ing the LIU tar­get of 2.6·1011 p/b. The thresh­old of lon­gi­tu­di­nal quadrupo­lar cou­pled-bunch in­sta­bil­i­ties is in­creased dur­ing ac­cel­er­a­tion, but they are again ob­served at the flat-top. While dipo­lar cou­pled-bunch os­cil­la­tions are well damped by a ded­i­cated feed­back sys­tem, the quadrupo­lar modes are sup­pressed by op­er­at­ing a 40 MHz sys­tem as an ac­tive higher-har­monic Lan­dau cav­ity. The main com­mis­sion­ing steps are out­lined, to­gether with the key con­tri­bu­tions to the im­proved beam per­for­mance.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK046  
About • Received ※ 07 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 16 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK059 Suppression of Emittance Growth by a Collective Force: Van Kampen Approach emittance, damping, cavity, impedance 2197
 
  • X. Buffat
    CERN, Meyrin, Switzerland
  
  In hadron syn­chro­trons, ex­ter­nal sources of noise af­fect­ing the beam in­duce emit­tance growth through the mech­a­nism of de­co­her­ence. Ac­tive feed­backs are often used to sup­press this emit­tance growth. In the pres­ence of beam-beam in­ter­ac­tions, it was shown that co­her­ent modes of os­cil­la­tions with fre­quen­cies shifted out­side of the in­co­her­ent spec­trum sig­nif­i­cantly en­hances the ef­fi­ciency of the emit­tance growth sup­pres­sion by ac­tive feed­backs. We show that the same en­hance­ment of the emit­tance growth sup­pres­sion may be dri­ven by a beam cou­pling im­ped­ance gen­er­at­ing a real tune shift larger than the de­tun­ing.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK059  
About • Received ※ 03 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 15 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS031 Light Path Construction for an Optical Stochastic Cooling Stability Test at the Cornell Electron Storage Ring radiation, experiment, synchrotron, optics 2315
 
  • S.J. Levenson, M.B. Andorf, I.V. Bazarov, D.C. Burke, J.M. Maxson, D.L. Rubin, S. Wang
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  
  Funding: This work was supported by the U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams and NYSTAR award C150153.
An ex­per­i­ment at the Cor­nell Elec­tron Stor­age Ring (CESR) to test the op­ti­cal path-length sta­bil­ity of a by­pass suit­able for Op­ti­cal Sto­chas­tic Cool­ing (OSC) is being pur­sued. The ap­prox­i­mately 80 m light path for this ex­per­i­ment has been as­sem­bled, and syn­chro­tron light has been suc­cess­fully prop­a­gated from both sources. A feed­back sys­tem based on an Elec­tro-Op­tic Mod­u­la­tor (EOM) to cor­rect the path-er­ror ac­cu­mu­lated in both the light and par­ti­cle path has been table-top tested. We pre­sent on the de­sign and con­struc­tion of the light op­tics for the OSC sta­bil­ity ex­per­i­ment at CESR. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS031  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST029 Upgrade of the Slow Extraction System of the Heidelberg Ion-Beam Therapy Centre’s Synchrotron extraction, synchrotron, experiment, FEL 2509
 
  • E. Feldmeier, R. Cee, E.C. Cortés García, M. Galonska, Th. Haberer, M. Hun, A. Peters, S. Scheloske, C. Schömers
    HIT, Heidelberg, Germany
  
  The Hei­del­berg Ion-Beam Ther­apy Cen­tre HIT con­sists of a lin­ear ac­cel­er­a­tor and a syn­chro­tron to pro­vide car­bon ions, he­lium ions and pro­tons for the clin­i­cal use as well as oxy­gen ions for ex­per­i­ments. The RF-KO slow ex­trac­tion method is used to ex­tract the par­ti­cles from the syn­chro­tron. To im­prove the spill qual­ity of the ex­tracted beam a new RF-sig­nal was in­ves­ti­gated which in­creases the R-value from 92.5% to 97,5%. The sig­nal is a multi­band RF sig­nal broad­ened with a ran­dom BPSK at 3 fre­quency bands.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST029  
About • Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT008 Beam Orbit Shift Due to BPM Thermal Deformation Using Machine Learning network, storage-ring, synchrotron, vacuum 2577
 
  • K.M. Chen, M. Hosaka, F.Y. Wang, G. Wang, Z. Wang, W. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  • L. Guo
    Nagoya University, Nagoya, Japan
  
  Sta­bi­liz­ing beam orbit is crit­i­cal for ad­vanced syn­chro­tron ra­di­a­tion light sources. The beam orbit can be af­fected by many sources. To main­tain a good orbit sta­bil­ity, global orbit feed­back sys­tems (OFB) has been widely used. How­ever, the BPM ther­mal de­for­ma­tion would lead to BPM mis­read­ing, which can not be han­dled by OFB. Usu­ally, extra di­ag­nos­tics, such as po­si­tion trans­duc­ers, is needed to mea­sure the de­for­ma­tion de­pen­dency of BPM read­ings. Here, an al­ter­na­tive ap­proach by using the ma­chine op­er­a­tion his­toric data, in­clud­ing BPM tem­per­a­ture, in­ser­tion de­vice (ID) gaps and cor­rec­tor cur­rents, is pre­sented. It is demon­strated at Hefei Light Source (HLS). The av­er­age orbit shift due to BPM ther­mal de­for­ma­tion is about 34.5 mi­crons/de­gree Cel­sius (hor­i­zon­tal) and 20.0 mi­crons/de­gree Cel­sius (ver­ti­cal).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT008  
About • Received ※ 19 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT009 Dependency Measurement of BPM Reading in the HLS-II Storage Ring operation, storage-ring, electronics, electron 2580
 
  • G. Wang, K.M. Chen, G. Feng, M. Hosaka, Z. Wang, W. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  • L. Guo
    Nagoya University, Nagoya, Japan
  • S.W. Wang
    DLS, Oxfordshire, United Kingdom
  
  Beam orbit sta­bil­ity is es­sen­tial for the op­er­a­tion of the stor­age ring based light sources. Orbit feed­back sys­tems are com­monly adopted to main­tain the beam on a ref­er­ence orbit. How­ever, the BPM read­ing could be af­fected by its tem­per­a­ture, beam cur­rent, etc, which leads to shift of the beam ref­er­ence orbit. On­line ex­per­i­ment is car­ried out in the HLS-II stor­age ring to study the de­pen­dence of the beam ref­er­ence orbit on the BPM tem­per­a­ture and beam cur­rent. The re­sult shows that the av­er­age change of BPM read­ings due to BPM tem­per­a­ture is about 37.4 ’m/’C hor­i­zon­tally and 11.5 ’m/’C ver­ti­cally. The av­er­age change of BPM read­ings in­duced by beam cur­rent is about 0.27 ’m/mA hor­i­zon­tally and 0.20 ’m/mA ver­ti­cally.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT009  
About • Received ※ 19 May 2022 — Revised ※ 23 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT048 Impact of IDs on the Diamond Storage Ring and Application to Diamond-II photon, electron, storage-ring, emittance 2705
 
  • R.T. Fielder, B. Singh
    DLS, Oxfordshire, United Kingdom
  
  When in­ves­ti­gat­ing the ef­fect of in­ser­tion de­vices (IDs) on stor­age ring op­er­a­tions, it is not pos­si­ble to sim­u­late all of the large num­ber of gap, phase and field set­tings that are avail­able. This can be of par­tic­u­lar con­cern for tran­sient ef­fects in IDs that are moved fre­quently, or AP­PLE-II de­vices which may use many dif­fer­ent po­lar­i­sa­tion states. We there­fore pre­sent mea­sure­ments of the im­pact of se­lected IDs on var­i­ous pa­ra­me­ters in the cur­rent Di­a­mond stor­age ring in­clud­ing orbit dis­tor­tion, tunes, chro­matic­ity and emit­tance, and as­sess the ex­pected im­pact when ap­plied to the Di­a­mond-II lat­tice.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT048  
About • Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK040 Few-Nanosecond Stripline Kickers for Top-Up Injection into PETRA IV kicker, injection, vacuum, synchrotron 2858
 
  • G. Loisch, V. Belokurov, F. Obier
    DESY, Hamburg, Germany
  
  PETRA IV is the planned ul­tralow-emit­tance up­grade of the PETRA III syn­chro­tron light source at DESY, Ham­burg. The cur­rent base­line in­jec­tion scheme is an off-axis, top-up in­jec­tion with few-nanosec­ond stripline kick­ers, which would allow for ac­cu­mu­la­tion and least dis­tur­bance of ex­per­i­ments dur­ing in­jec­tion. Be­sides the re­quire­ments on kick-strength, field qual­ity, pulse rise-rate, and heat man­age­ment, two me­chan­i­cal de­signs with dif­fer­ent aper­tures are nec­es­sary, as the de­vices will be used for in­jec­tion and the trans­verse multi-bunch feed­back sys­tem. In this con­tri­bu­tion we will pre­sent the cur­rent sta­tus of 3D fi­nite el­e­ment sim­u­la­tions of elec­tro­mag­netic fields and heat­ing as well as the me­chan­i­cal de­sign and first pulse elec­tron­ics tests.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK040  
About • Received ※ 20 May 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FRIXGD1 Status and Prospects in Fast Beam-Based Feedbacks kicker, cavity, pick-up, hadron 3112
 
  • W. Höfle
    CERN, Meyrin, Switzerland
  
  Fast beam-based Feed­back sys­tems play an im­por­tant role in cir­cu­lar ac­cel­er­a­tors to mit­i­gate in­sta­bil­i­ties and re­duce the im­pact of in­jec­tion os­cil­la­tions and per­tur­ba­tions on beam qual­ity, both in the lon­gi­tu­di­nal and trans­verse planes. The sta­tus and prospects of such beam-based feed­back sys­tems for cir­cu­lar ac­cel­er­a­tors are re­viewed. This in­cludes progress to­wards the fun­da­men­tal lim­its in noise and feed­back gain and the pos­si­bil­i­ties of mod­ern dig­i­tal sys­tems to ex­tract large amounts of data that can be used to char­ac­terise beam prop­er­ties. The talk con­cen­trates on ma­chines with hadrons and gives an out­look on pos­si­ble de­vel­op­ments for fu­ture ac­cel­er­a­tor pro­jects under study.  
slides icon Slides FRIXGD1 [3.562 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FRIXGD1  
About • Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)