Keyword: octupole
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MOXB02 First Results of the IOTA Ring Research at Fermilab experiment, electron, optics, lattice 19
 
  • A. Valishev, D.R. Broemmelsiek, A.V. Burov, K. Carlson, B.L. Cathey, S. Chattopadhyay, N. Eddy, D.R. Edstrom, J.D. Jarvis, V.A. Lebedev, S. Nagaitsev, H. Piekarz, A.L. Romanov, J. Ruan, J.K. Santucci, V.D. Shiltsev, G. Stancari
    Fermilab, Batavia, Illinois, USA
  • A. Arodzero, A.Y. Murokh, M. Ruelas
    RadiaBeam, Santa Monica, California, USA
  • D.L. Bruhwiler, J.P. Edelen, C.C. Hall
    RadiaSoft LLC, Boulder, Colorado, USA
  • S. Chattopadhyay, S. Szustkowski
    Northern Illinois University, DeKalb, Illinois, USA
  • A. Halavanau, Z. Huang, V. Yakimenko
    SLAC, Menlo Park, California, USA
  • M. Hofer
    TU Vienna, Wien, Austria
  • M. Hofer, R. Tomás García
    CERN, Geneva, Switzerland
  • K. Hwang, C.E. Mitchell, R.D. Ryne
    LBNL, Berkeley, California, USA
  • K.-J. Kim
    ANL, Lemont, Illinois, USA
  • K.-J. Kim, Y.K. Kim, N. Kuklev, I. Lobach
    University of Chicago, Chicago, Illinois, USA
  • T.V. Shaftan
    BNL, Upton, New York, USA
  
  Funding: Fermilab is operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The IOTA ring at Fer­mi­lab is a unique ma­chine ex­clu­sively ded­i­cated to ac­cel­er­a­tor beam physics R&D. The re­search con­ducted at IOTA in­cludes top­ics such as non­lin­ear in­te­grable op­tics, sup­pres­sion of co­her­ent beam in­sta­bil­i­ties, op­ti­cal sto­chas­tic cool­ing and quan­tum sci­ence ex­per­i­ments. In this talk we re­port on the first re­sults of ex­per­i­ments with im­ple­men­ta­tions of non­lin­ear in­te­grable beam op­tics. The first of its kind prac­ti­cal re­al­iza­tion of a two-di­men­sional in­te­grable sys­tem in a strongly-fo­cus­ing stor­age ring was demon­strated al­low­ing among other things for sta­ble beam cir­cu­la­tion near or at the in­te­ger res­o­nance. Also pre­sented will be the high­lights of the world’s first demon­stra­tion of op­ti­cal sto­chas­tic beam cool­ing and other se­lected re­sults of IOTA’s broad ex­per­i­men­tal pro­gram. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOXB02  
About • paper received ※ 20 May 2021       paper accepted ※ 02 July 2021       issue date ※ 23 August 2021  
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MOPAB008 Exploiting the Beam-Beam Wire Demonstrators in the Next LHC Run 3 luminosity, operation, experiment, quadrupole 65
 
  • A. Poyet
    Université Grenoble Alpes, Grenoble, France
  • S.D. Fartoukh, N. Karastathis, Y. Papaphilippou, A. Rossi, G. Sterbini
    CERN, Geneva, Switzerland
  • K. Skoufaris
    University of Crete, Heraklion, Crete, Greece
  
  After the suc­cess­ful ex­per­i­ments per­formed dur­ing the LHC Run 2 with the Beam-Beam Wire demon­stra­tors in­stalled, on Beam 2, in the frame of the HL-LHC pro­ject, two of the four wire demon­stra­tors were moved to Beam 1. The ob­jec­tive is to gain op­er­a­tional ex­pe­ri­ence with the wire com­pen­sa­tion also on that beam and there­fore fully ex­ploit the demon­stra­tors’ po­ten­tial. This paper pro­poses a nu­mer­i­cal val­i­da­tion of the wire im­ple­men­ta­tion using Run 3 sce­nar­ios and ex­plores the op­ti­miza­tion of those de­vices in that re­spect.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB008  
About • paper received ※ 17 May 2021       paper accepted ※ 24 May 2021       issue date ※ 11 August 2021  
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MOPAB035 Modified Lattice of the Compact Storage Ring in the cSTART Project at Karlsruhe Institute of Technology sextupole, quadrupole, lattice, storage-ring 159
 
  • A.I. Papash, E. Bründermann, B. Härer, A.-S. Müller, R. Ruprecht, J. Schäfer, M. Schuh
    KIT, Karlsruhe, Germany
  
  A very large ac­cep­tance com­pact stor­age ring (VLA-cSR) is under de­sign at the In­sti­tute for Beam Physics and Tech­nol­ogy (IBPT) of the Karl­sruhe In­sti­tute of Tech­nol­ogy (KIT, Ger­many). The com­bi­na­tion of a com­pact stor­age ring and a laser wake­field ac­cel­er­a­tor (LWFA) might be the basis for fu­ture com­pact light sources and ad­vanc­ing user fa­cil­i­ties. Mean­while, the post-LWFA beam should be adapted for stor­age and ac­cu­mu­la­tion in a ded­i­cated stor­age ring. Mod­i­fied geom­e­try and lat­tice of a VLA-cSR op­er­at­ing at 50 MeV en­ergy range have been stud­ied in de­tailed sim­u­la­tions. The main fea­tures of a new model are de­scribed here. The new de­sign, based on 45° bend­ing mag­nets, is suit­able to store the post-LWFA beam with a wide mo­men­tum spread (1% to 2%) as well as ul­tra-short elec­tron bunches in the fs range from the Fer­n­in­frarot Linac- Und Test- Ex­per­i­ment (FLUTE). The DBA-FDF lat­tice with re­laxed set­tings, split el­e­ments, and higher-or­der op­tics of tol­er­a­ble strength al­lows im­prov­ing the dy­namic aper­ture to an ac­cept­able level. This con­tri­bu­tion dis­cusses the lat­tice fea­tures in de­tail and dif­fer­ent pos­si­ble op­er­a­tion schemes of a VLA-cSR.  
poster icon Poster MOPAB035 [1.405 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB035  
About • paper received ※ 10 May 2021       paper accepted ※ 27 May 2021       issue date ※ 24 August 2021  
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MOPAB066 Dual Octupole Emittance Growth Correction of the CompactLight XFEL Bunch Compressors emittance, FEL, lattice, linac 272
 
  • R. Auchettl, R.T. Dowd
    AS - ANSTO, Clayton, Australia
  
  An op­ti­mized Com­pact­Light X-Ray Free Elec­tron Laser (FEL) bunch com­pres­sor de­sign is pre­sented. In this work, we in­sert an oc­tu­pole into the cen­ter of the two se­quen­tial bunch com­pres­sors. We show how this scheme can ad­just the com­pres­sion, while cor­rect­ing the un­de­sir­able peak cur­rent pro­file and emit­tance growth.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB066  
About • paper received ※ 24 May 2021       paper accepted ※ 28 May 2021       issue date ※ 24 August 2021  
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MOPAB231 Tunability Study of the Ultra-Low β* Optics at ATF2 with New Octupole Setup and Tuning Knobs optics, alignment, simulation, quadrupole 752
 
  • A. Pastushenko, R. Tomás García
    CERN, Geneva, Switzerland
  • A. Faus-Golfe
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • K. Kubo, S. Kuroda, T. Naito, T. Okugi, N. Terunuma, R.J. Yang
    KEK, Ibaraki, Japan
  
  The main goal of the Ac­cel­er­a­tor Test Fa­cil­ity 2 (ATF2) is to demon­strate the fea­si­bil­ity of fu­ture lin­ear col­lid­ers’ final focus sys­tems. The Ul­tra-low β* op­tics of ATF2 is de­signed to have the same chro­matic­ity level as CLIC. To ease the tun­ing pro­ce­dure, a pair of oc­tupoles was in­stalled in ATF2 in 2017. This paper re­ports the op­ti­miza­tions per­formed to the oc­tupoles’ setup for Ul­tra-low β* op­tics in­clud­ing the new align­ment tech­nique, based on the waist shift and the new tun­ning knobs con­structed for this op­tics. The full tun­ing pro­ce­dure in­clud­ing the sta­tic er­rors is sim­u­lated for this setup.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB231  
About • paper received ※ 19 May 2021       paper accepted ※ 28 July 2021       issue date ※ 12 August 2021  
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TUPAB224 Non-Linear Variation of the Beta-Beating Measured From Amplitude simulation, optics, resonance, target 1949
 
  • T. Pugnat, B. Dalena
    CEA-IRFU, Gif-sur-Yvette, France
  • A. Franchi
    ESRF, Grenoble, France
  • R. Tomás García
    CERN, Geneva, Switzerland
  
  Ac­cel­er­a­tor physics needs ad­vanced mod­el­ing and sim­u­la­tion tech­niques, for beam sta­bil­ity stud­ies but also for the mea­sure­ment of beam pa­ra­me­ters like the Twiss pa­ra­me­ters. A deeper un­der­stand­ing of mag­netic field non-lin­ear­i­ties ef­fects will greatly help in the im­prove­ment of fu­ture cir­cu­lar col­lider de­sign, per­for­mance, and di­ag­nos­tics. This paper stud­ies the vari­a­tion of the \beta-beat­ing with the ac­tion of the par­ti­cle gen­er­ated by non-lin­ear Res­o­nance Dri­ving Terms, both from a the­o­ret­i­cal and an ex­per­i­men­tal point of view.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB224  
About • paper received ※ 18 May 2021       paper accepted ※ 06 July 2021       issue date ※ 21 August 2021  
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TUPAB225 3D Magnetic Field Analysis of LHC Final Focus Quadrupoles with Beam Screen quadrupole, focusing, HOM, database 1952
 
  • T. Pugnat, B. Dalena, C. Lorin
    CEA-IRFU, Gif-sur-Yvette, France
  • S. Bagnis
    CEA-DRF-IRFU, France
  
  Dur­ing the LHC com­mis­sion­ing, a dis­crep­ancy in the non-lin­ear cor­rec­tor strengths be­tween the model and the beam-based val­ues has been ob­served*. This has mo­ti­vated the re­con­struc­tion of the 3D fi­nite el­e­ment model for the LHC final fo­cus­ing MQXA type mag­net. The lon­gi­tu­di­nal higher or­ders mag­netic field pseudo-har­mon­ics are com­puted tak­ing into ac­count oval­iza­tion of the mag­net, in­ter­con­nec­tions de­sign, and beam screens. The ef­fect of this 3D field on the com­pu­ta­tion of the non­lin­ear cor­rec­tors is eval­u­ated and com­pared with beam-based cor­rec­tor val­ues.
*E. H. Maclean et al., "New approach to LHC optics commissioning for the nonlinear era", Phys. Rev. Acc. B, vol. 22, pp. 061004, June 2019. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB225  
About • paper received ※ 18 May 2021       paper accepted ※ 08 July 2021       issue date ※ 12 August 2021  
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TUPAB227 Simultaneous Compensation of Phase and Amplitude Dependent Geometrical Resonances Using Octupoles sextupole, lattice, emittance, resonance 1960
 
  • F. Plassard, Y. Hidaka, Y. Li, T.V. Shaftan, V.V. Smaluk, G.M. Wang
    BNL, Upton, New York, USA
  
  As the new gen­er­a­tion of light sources are push­ing to­ward dif­frac­tion lim­ited stor­age rings with ul­tra-low emit­tance beams, non­lin­ear beam dy­nam­ics be­come in­creas­ingly dif­fi­cult to con­trol. It is a com­mon prac­tice for mod­ern de­signs to use a sex­tu­pole scheme that al­lows si­mul­ta­ne­ous cor­rec­tion of nat­ural chro­matic­ity and en­ergy in­de­pen­dent, or geo­met­ri­cal, sex­tupo­lar res­o­nances. How­ever, the re­main­ing higher order terms aris­ing from the cross talks of the sex­tu­pole fam­i­lies set a strong lim­i­ta­tion on the achiev­able dy­namic aper­ture. This paper pre­sents a sim­u­la­tion-based recipe to use oc­tupoles to­gether with this sex­tu­pole scheme to pro­vide si­mul­ta­ne­ous self-com­pen­sa­tion of lin­ear am­pli­tude de­pen­dent tune shift to­gether with phase-de­pen­dent oc­tupo­lar and higher order geo­met­ri­cal res­o­nant dri­ving terms. The cor­rec­tion method was built based on ob­ser­va­tions made on a sim­ple FODO model, then ap­plied to a re­al­is­tic low emit­tance lat­tice, de­signed in the frame­work of the up­grade of the Na­tional Syn­chro­tron Light Source II (NSLS-II).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB227  
About • paper received ※ 19 May 2021       paper accepted ※ 23 June 2021       issue date ※ 14 August 2021  
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TUPAB228 IOTA Run 2 Beam Dynamics Studies in Nonlinear Integrable Systems optics, experiment, lattice, simulation 1964
 
  • N. Kuklev, Y.K. Kim
    University of Chicago, Chicago, Illinois, USA
  • S. Nagaitsev, A.L. Romanov, A. Valishev
    Fermilab, Batavia, Illinois, USA
  
  Funding: Work supported by the U.S. NSF under award PHY-1549132, the Center for Bright Beams. Fermi Research Alliance, LLC operates Fermilab under Contract DE-AC02-07CH11359 with the US Department of Energy.
Non­lin­ear in­te­grable op­tics is a promis­ing de­sign ap­proach for sup­press­ing fast col­lec­tive in­sta­bil­i­ties. To study it ex­per­i­men­tally, a new stor­age ring, the In­te­grable Op­tics Test Ac­cel­er­a­tor (IOTA), was built at Fer­mi­lab. IOTA has re­cently com­pleted its sec­ond sci­en­tific run, in­cor­po­rat­ing many hard­ware and in­stru­men­ta­tion im­prove­ments. This re­port pre­sents the re­sults of the two in­te­grable op­tics ex­per­i­ments - the quasi-in­te­grable Henon-Heiles oc­tu­pole sys­tem and the fully in­te­grable Danilov-Na­gait­sev sys­tem. We demon­strate tune spread and dy­namic aper­ture in agree­ment with track­ing sim­u­la­tions, and a sta­ble cross­ing of the in­te­ger res­o­nance. Based on re­cov­ered sin­gle-par­ti­cle phase space dy­nam­ics, we show im­proved in­vari­ant jit­ter con­sis­tent with in­tended ef­fec­tive Hamil­ton­ian. We con­clude by out­lin­ing fu­ture plans and ef­forts to­wards pro­ton stud­ies and larger de­signs. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB228  
About • paper received ※ 31 May 2021       paper accepted ※ 23 June 2021       issue date ※ 10 August 2021  
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TUPAB234 Exploring Accelerators for Intense Beams with the IBEX Paul Trap lattice, quadrupole, experiment, simulation 1980
 
  • J.A.D. Flowerdew
    University of Oxford, Oxford, United Kingdom
  • D.J. Kelliher, S. Machida
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • S.L. Sheehy
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  
  Ac­cel­er­a­tors built from lin­ear com­po­nents will ex­hibit bounded and sta­ble par­ti­cle mo­tion in the ideal case. How­ever, any im­per­fec­tions in field strength or mis­align­ment of com­po­nents can in­tro­duce chaotic and un­sta­ble par­ti­cle mo­tion. All ac­cel­er­a­tors are prone to such non-lin­ear­i­ties but the ef­fects are even more sig­nif­i­cant in high in­ten­sity par­ti­cle beams with the pres­ence of space charge ef­fects. This work aims to ex­plore the non-lin­ear­i­ties which arise in high in­ten­sity par­ti­cle beams using the scaled ex­per­i­ment, IBEX. The IBEX ex­per­i­ment is a lin­ear Paul trap that al­lows the trans­verse dy­nam­ics of a col­lec­tion of trapped par­ti­cles to be stud­ied by mim­ic­k­ing the prop­a­ga­tion through mul­ti­ple quadru­pole lat­tice pe­ri­ods whilst re­main­ing sta­tion­ary in the lab­o­ra­tory frame. IBEX is cur­rently un­der­go­ing a non-lin­ear up­grade with the goal of in­ves­ti­gat­ing Non-lin­ear In­te­grable Op­tics (NIO) in order to im­prove our un­der­stand­ing and util­i­sa­tion of high in­ten­sity par­ti­cle beams.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB234  
About • paper received ※ 19 May 2021       paper accepted ※ 18 June 2021       issue date ※ 12 August 2021  
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TUPAB238 Algorithm to Analyze Complex Magnetic Structures Using a Tube Approach quadrupole, multipole, HOM, sextupole 1995
 
  • B. Riemann, M. Aiba
    PSI, Villigen PSI, Switzerland
  
  Mod­ern syn­chro­tron light sources often re­quire so­phis­ti­cated mul­ti­pole field dis­tri­b­u­tions that need to be re­al­ized by com­plex mag­net struc­tures. To pre-val­i­date these mag­net struc­tures via sim­u­la­tions, the ex­trac­tion pro­ce­dure needs to out­put stan­dard mul­ti­poles as well as fringe ef­fects. The ap­proach pre­sented in this man­u­script uses a vol­u­met­ric grid map of the mag­netic flux den­sity as input. After com­pu­ta­tion of the ref­er­ence tra­jec­tory (leapfrog in­te­gra­tion), a large lin­ear sys­tem is solved to com­pute trans­verse poly­no­mial co­ef­fi­cients of the mag­netic scalar po­ten­tial in a se­ries of in­ter­con­nected thin cylin­ders (lin­ear basis func­tions) along with that ref­er­ence. The im­port of these co­ef­fi­cients into a lat­tice sim­u­la­tion is dis­cussed using a mod­i­fi­ca­tion of the track­ing code Tracy. The shown ap­proach is rou­tinely used to check mod­els of SLS 2.0 mag­nets for their prop­er­ties.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB238  
About • paper received ※ 18 May 2021       paper accepted ※ 17 June 2021       issue date ※ 31 August 2021  
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WEPAB259 Impact of the Magnet Alignment and Field Errors on the Output Uniform Beam at the DONES HEBT Line target, neutron, multipole, linac 3251
 
  • C. Oliver, A. Ibarra, J. Mollá, I. Podadera, R. Varela
    CIEMAT, Madrid, Spain
  • H. Dzitko
    F4E, Germany
  • O. Nomen, D. Sánchez-Herranz
    IREC, Sant Adria del Besos, Spain
  
  Funding: This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 under grant agreement No 633053
IFMIF-DONES will be a fa­cil­ity de­voted to study the degra­da­tion of ad­vanced ma­te­ri­als for op­er­a­tion of fu­sion re­ac­tors. Mo­ti­vated by the need of op­ti­miz­ing the neu­tron ir­ra­di­a­tion to the ma­te­ri­als sam­ples, the HEBT line of the deuteron DONES (DEMO Ori­ented Neu­tron Source) ac­cel­er­a­tor is based on non-lin­ear mag­netic fields. By using oc­tupoles and do­de­capoles mag­nets, it is pos­si­ble to shape the beam pro­file to achieve the de­manded rec­tan­gu­lar uni­form dis­tri­b­u­tion across the flat top of the beam pro­file, with high edge peaks in the hor­i­zon­tal di­rec­tion. Spe­cial op­tics con­di­tions are ob­tained with a proper set­ting of quadru­pole mag­nets to min­i­mize the x-y cou­pling. Ad­di­tion­ally, the high beam power (5 MW, for a 125 mA, 40 MeV deuteron beam) in con­junc­tion with the huge space charge makes chal­leng­ing the HEBT line de­sign to avoid non-con­trolled losses, ex­cept in the de­voted scrap­ers. A com­pre­hen­sive beam dy­nam­ics analy­sis has been made using TraceWin code. It in­cludes ex­ten­sive error stud­ies to de­fine tol­er­ances and ver­ify the ro­bust­ness of the de­sign with re­spect to mag­net mis­align­ment, power sup­ply in­sta­bil­i­ties and in­jec­tion pa­ra­me­ters. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB259  
About • paper received ※ 19 May 2021       paper accepted ※ 26 July 2021       issue date ※ 17 August 2021  
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THPAB073 Study of Seven-Bend-Achromat Lattice Option for Half lattice, emittance, storage-ring, sextupole 3926
 
  • J.H. Xu, Z.H. Bai, Z.L. Ren, J.J. Tan, P.H. Yang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  • Q. Zhang
    INEST, Hefei, People’s Republic of China
  
  A seven-bend-achro­mat (7BA) stor­age ring lat­tice de­sign for Hefei Ad­vanced Light Fa­cil­ity (HALF) with a beam en­ergy of 2.2 GeV and a cir­cum­fer­ence of 388.8 m is pre­sented. The 7BA lat­tice is de­signed with the com­bined func­tion bends and re­verse bends which has a nat­ural emit­tance of about 67 pm·rad. Two lat­tice can­di­dates with dif­fer­ent tunes have been se­lected. One lat­tice has bet­ter non­lin­ear dy­namic per­for­mance for off-axis in­jec­tion. The other lat­tice pro­vides lower beta func­tions at the cen­ter of straight sec­tions. The re­sults of these stud­ies are dis­cussed in this paper.  
poster icon Poster THPAB073 [1.146 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB073  
About • paper received ※ 15 May 2021       paper accepted ※ 28 July 2021       issue date ※ 16 August 2021  
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THPAB169 A Mechanism for Emittance Growth Based on Non-Linear Islands in LHC emittance, ECR, operation, resonance 4082
 
  • E.H. Maclean, M. Giovannozzi, T.H.B. Persson, R. Tomás García
    CERN, Geneva, Switzerland
  
  Lan­dau oc­tupoles are used in the LHC to pre­vent co­her­ent in­sta­bil­i­ties of the cir­cu­lat­ing beam. The re­duc­tion of their strength oc­cur­ring dur­ing the en­ergy ramp can trans­port par­ti­cles in non­lin­ear is­lands to larger am­pli­tude. This has the po­ten­tial to lead to emit­tance growth and to beam-losses. Beam-based stud­ies and sim­u­la­tions of emit­tance growth dur­ing Lan­dau oc­tu­pole ramps per­formed in the LHC are pre­sented to ex­plore this mech­a­nism in more de­tail.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB169  
About • paper received ※ 18 May 2021       paper accepted ※ 14 July 2021       issue date ※ 14 August 2021  
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THPAB206 Validating pyORBIT for Modeling Beam Dynamics in the IOTA Ring space-charge, proton, emittance, dynamic-aperture 4190
 
  • R. Li
    UW-Madison/PD, Madison, Wisconsin, USA
  • J.-F. Ostiguy, T. Sen
    Fermilab, Batavia, Illinois, USA
  
  Funding: Supported by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics.
The In­te­grable Op­tics Test Ac­cel­er­a­tor (IOTA) ring is a new Fer­mi­lab fa­cil­ity ded­i­cated to beam physics ex­per­i­ments, cur­rently op­er­at­ing with 150 MeV elec­trons. Space charge ef­fects are ex­pected to be sig­nif­i­cant when it op­er­ates with 2.5 MeV pro­tons. In this con­tri­bu­tion, we pre­sent re­sults of a suite of val­i­da­tion tests of Py­OR­BIT, a PIC­style space charge code. Sin­gle par­ti­cle dy­nam­ics of qua­si­in­te­grable op­tics using an oc­tu­pole string in IOTA is com­pared with MADX, and shown to be in good agree­ment. Re­quire­ments for the con­ver­gence of space charge com­pu­ta­tions are sys­tem­at­i­cally es­tab­lished and when pos­si­ble, tests in­volv­ing space charge are com­pared with the­o­ret­i­cal pre­dic­tions. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB206  
About • paper received ※ 19 May 2021       paper accepted ※ 08 July 2021       issue date ※ 12 August 2021  
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