Author: Persson, T.H.B.
Paper Title Page
MOPAB007 Prospect for Interaction Region Local Coupling Correction in the LHC Run 3 61
 
  • F. Soubelet, T.H.B. Persson, R. Tomás García
    CERN, Geneva, Switzerland
  • O. Apsimon, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • O. Apsimon, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  
  Funding: This work was supported by STFC Liverpool Centre for Doctoral Training on Data Intensive Science (LIV. DAT) and CERN.
Suc­cess­ful op­er­a­tion of large scale par­ti­cle ac­cel­er­a­tors de­pends on the pre­cise cor­rec­tion of un­avoid­able mag­net field or align­ment er­rors pre­sent in the ma­chine. In the LHC Run 2, local lin­ear cou­pling in the In­ter­ac­tion Re­gions (IR) has been proven to have a se­vere im­pact on beam size and hence the lu­mi­nos­ity - up to a 50% de­crease -, mak­ing its han­dling a tar­get for Run 3 and High Lu­mi­nos­ity LHC (HL-LHC). How­ever, cur­rent mea­sure­ment meth­ods are not op­ti­mised for local IR cou­pling. In this con­tri­bu­tion, an ap­proach to ac­cu­rately min­imise IR local cou­pling based on cor­re­lated ex­ter­nal vari­ables such as the |C-| is pro­posed. The va­lid­ity of the method is demon­strated through sim­u­la­tions and bench­marked against the­o­ret­i­cal val­ues, such as Res­o­nance Dri­ving Terms (RDTs) and Rip­ken pa­ra­me­ters. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB007  
About • paper received ※ 17 May 2021       paper accepted ※ 23 July 2021       issue date ※ 19 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPAB004 Comparison of Accelerator Codes for Simulation of Lepton Colliders 1334
 
  • L. van Riesen-Haupt, H. Burkhardt, T.H.B. Persson, R. Tomás García
    CERN, Geneva, Switzerland
  
  This paper com­pares sim­u­la­tion re­sults ob­tained with SAD, MAD-X and the PTC im­ple­men­ta­tion in MADX for the de­sign stud­ies of the FCC-ee. On-mo­men­tum and off-mo­men­tum op­tics are ex­plored for the var­i­ous pro­grams. Par­ti­cle track­ing with and with­out syn­chro­tron ra­di­a­tion are used to com­pare am­pli­tude de­tun­ing and emit­tance. Fi­nally, this paper out­lines how well-es­tab­lished SAD fea­tures such as ta­per­ing have re­cently been in­te­grated into MADX.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB004  
About • paper received ※ 16 May 2021       paper accepted ※ 15 June 2021       issue date ※ 26 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPAB026 Optics Measurements and Correction Plans for the HL-LHC 2656
 
  • T.H.B. Persson, X. Buffat, F.S. Carlier, R. De Maria, J. Dilly, E. Fol, D. Gamba, H. Garcia Morales, A. García-Tabarés Valdivieso, M. Giovannozzi, M. Hofer, E.J. Høydalsvik, J. Keintzel, M. Le Garrec, E.H. Maclean, L. Malina, P.K. Skowroński, F. Soubelet, R. Tomás García, F.F. Van der Veken, A. Wegscheider, D.W. Wolf, L. van Riesen-Haupt
    CERN, Meyrin, Switzerland
  • J.M. Coello de Portugal
    PSI, Villigen PSI, Switzerland
  
  The High Lu­mi­nos­ity LHC (HL-LHC) will re­quire strin­gent op­tics cor­rec­tion to op­er­ate safely and de­liver the de­sign lu­mi­nos­ity to the ex­per­i­ments. In order to achieve this, sev­eral new meth­ods for op­tics cor­rec­tion have been de­vel­oped. In this ar­ti­cle, we out­line some of these meth­ods and we de­scribe the en­vi­sioned strat­egy of how to use them in order to reach the chal­leng­ing re­quire­ments of the HL-LHC physics pro­gram.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB026  
About • paper received ※ 17 May 2021       paper accepted ※ 27 July 2021       issue date ※ 30 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPAB027 Optics Correction Strategy for Run 3 of the LHC 2660
 
  • T.H.B. Persson, R. De Maria, J. Dilly, E. Fol, H. Garcia Morales, M. Hofer, E.J. Høydalsvik, J. Keintzel, M. Le Garrec, E.H. Maclean, L. Malina, F. Soubelet, R. Tomás García, A. Wegscheider, D.W. Wolf, L. van Riesen-Haupt
    CERN, Meyrin, Switzerland
  • J.F. Cardona
    UNAL, Bogota D.C, Colombia
  
  The Run 3 of the LHC will con­tinue to pro­vide new chal­lenges for op­tics cor­rec­tions. In order to suc­ceed and go be­yond what was achieved pre­vi­ously, sev­eral new meth­ods to mea­sure and cor­rect the op­tics have been de­vel­oped. In this ar­ti­cle we de­scribe these meth­ods and out­line the plans for the op­tics com­mis­sion­ing in 2022.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB027  
About • paper received ※ 17 May 2021       paper accepted ※ 12 July 2021       issue date ※ 11 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPAB028 MAD-X for Future Accelerators 2664
 
  • T.H.B. Persson, H. Burkhardt, L. Deniau, A. Latina, P.K. Skowroński
    CERN, Geneva, Switzerland
  
  The fea­si­bil­ity and per­for­mance of the fu­ture ac­cel­er­a­tors must, to a large ex­tent, be pre­dicted by sim­u­la­tion codes. This im­plies that sim­u­la­tion codes need to in­clude ef­fects that pre­vi­ously played a minor role. For ex­am­ple, in large elec­tron ma­chines like the FCC-ee the large en­ergy vari­a­tion along the ring re­quires that the mag­nets strength is ad­justed to the beam en­ergy at that lo­ca­tion, nor­mally re­ferred to as ta­per­ing. In this ar­ti­cle, we pre­sent new fea­tures im­ple­mented in the MAD-X code to en­able and fa­cil­i­tate sim­u­la­tions of fu­ture col­lid­ers.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB028  
About • paper received ※ 17 May 2021       paper accepted ※ 06 July 2021       issue date ※ 27 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPAB001 Reaching the Sub Per Mil Level Coupling Corrections in the LHC 3752
 
  • E.J. Høydalsvik, T.H.B. Persson
    CERN, Geneva, Switzerland
  
  The High Lu­mi­nos­ity LHC (HL-LHC) is re­quir­ing sub per mil cou­pling cor­rec­tion, as de­fined by the clos­est tune ap­proach. In this ar­ti­cle, the cur­rent cou­pling cor­rec­tion strat­egy is an­a­lyzed in order to un­der­stand if it can ro­bustly cor­rect to these very low lev­els. The im­pact of re­al­is­tic er­rors on the cou­pling cor­rec­tion is in­ves­ti­gated with MAD-X sim­u­la­tions, in­clud­ing the in­flu­ence of local cou­pling on the global cou­pling cor­rec­tion. Through sim­u­la­tions and mea­sure­ments in the LHC, the ef­fect of BPM noise on the cou­pling cor­rec­tion is an­a­lyzed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB001  
About • paper received ※ 11 May 2021       paper accepted ※ 28 July 2021       issue date ※ 23 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPAB168 Optics Measurement by Excitation of Betatron Oscillations in the CERN PSB 4078
 
  • E.H. Maclean, F. Antoniou, F. Asvesta, H. Bartosik, C. Bracco, J. Dilly, E. Fol, H. Garcia Morales, M. Hofer, J. Keintzel, M. Le Garrec, T.E. Levens, L. Malina, T.H.B. Persson, T. Prebibaj, E. Renner, P.K. Skowroński, F. Soubelet, R. Tomás García, A. Wegscheider, L. van Riesen-Haupt
    CERN, Meyrin, Switzerland
  
  Op­tics mea­sure­ment from analy­sis of turn-by-turn BPM data of be­ta­tron os­cil­la­tions ex­cited with a kicker mag­net has been em­ployed very suc­cess­fully in many ma­chines but faces par­tic­u­lar chal­lenges in the CERN PSB where BPM to BPM phase ad­vances are sub-op­ti­mal for op­tics re­con­struc­tion. Ex­pe­ri­ence using turn-by-turn os­cil­la­tion data for lin­ear op­tics mea­sure­ments dur­ing PSB com­mis­sion­ing in­2021 is pre­sented, with im­pli­ca­tions for the prospect of such tech­niques in the PSB more gen­er­ally.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB168  
About • paper received ※ 19 May 2021       paper accepted ※ 14 July 2021       issue date ※ 27 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPAB169 A Mechanism for Emittance Growth Based on Non-Linear Islands in LHC 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  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)