Author: Kayran, D.
Paper Title Page
TUPC045 Recirculating Electron Linacs (REL) for LHeC and eRHIC 1099
 
  • D. Trbojevic, J. Beebe-Wang, Y. Hao, D. Kayran, V. Litvinenko, V. Ptitsyn, N. Tsoupas
    BNL, Upton, Long Island, New York, USA
  
  Funding: Work performed under a Contract Number DE-AC02-98CH10886 with the auspices of the US Department of Energy.
We pre­sent a de­sign of a CW Elec­tron Re­cov­ery Linacs (ERL) for fu­ture elec­tron hadron col­lid­ers eRHIC and LHeC. In eRHIC, a six-pass ERL would be in­stalled in the ex­ist­ing tun­nel of the pre­sent Rel­a­tivis­tic Heavy Ion Col­lid­er (RHIC). The 5-30 GeV po­lar­ized elec­trons will col­lide with RHIC’s 50-250 (325) GeV po­lar­ized pro­tons or 20-100 (130) GeV/u heavy ions. In LHeC a 3-pass 60 GeV CW ERL will pro­duce po­lar­ized elec­trons for col­li­sions with 7 TeV pro­tons. After col­li­sion, elec­tron beam en­er­gy is re­cov­ered and elec­trons are dumped at low en­er­gy. Two su­per­con­duct­ing linacs are lo­cat­ed in the two straight sec­tions in both ERLs. The mul­ti­ple arcs are made of Flex­i­ble Mo­men­tum Com­paction lat­tice (FMC) al­low­ing ad­justable mo­men­tum com­paction for elec­trons with dif­fer­ent en­er­gies. The mul­ti­ple arcs, placed above each other, are matched to the two linac’s straight sec­tions with split­ters and com­bin­ers. 		 
 
THOBA02
 Experimental Demonstration of Suppression of Coherent Synchrotron Radiation Wake-field  
 
  • V. Yakimenko, A.V. Fedotov, M.G. Fedurin, D. Kayran, V. Litvinenko
    BNL, Upton, Long Island, New York, USA
  • P. Muggli
    MPI, Muenchen, Germany
  
  In this paper we re­port on a first ex­per­i­men­tal demon­stra­tion of co­her­ent syn­chrotron ra­di­a­tion (CSR) wake-field sup­pres­sion by a nar­row-gap vac­u­um cham­ber. In­crease in the beam en­er­gy spread and emit­tance due to emis­sion of co­her­ent syn­chrotron ra­di­a­tion (CSR) is con­sid­ered to be a lim­it­ing fac­tor a high-cur­rent high-bright­ness beams. At the Brookhaven Na­tion­al Lab­o­ra­to­ry Ac­cel­er­a­tor Test Fa­cil­i­ty (ATF) we ex­per­i­men­tal­ly demon­strat­ed the sup­pres­sion of CSR wake-field - both the av­er­age en­er­gy loss and he en­er­gy spread growth – using pol­ished Al plates. Well char­ac­ter­ized elec­tron bunch­es were prop­a­gat­ed through a bend­ing mag­net with two par­al­lel Al plates with gap con­trolled be­tween 1 mm to 12 mm. Con­trary to some the­o­ret­ic pre­dic­tions, our ex­per­i­men­tal re­sults show that clos­ing the plates sig­nif­i­cant­ly re­duces both the beam en­er­gy loss and CSR-in­duced beam en­er­gy spread. In this paper we pre­sent our ex­per­i­men­tal re­sults and com­pare then with rig­or­ous an­a­lyt­i­cal the­o­ry. These re­sults open a pos­si­bil­i­ty to pre­dict an­a­lyt­i­cal­ly CSR shield­ing of fu­ture high-cur­rent high-bright­ness beams.  
slides icon Slides THOBA02 [12.706 MB]  
 
THPS009 Coherent Electron Cooling Demonstration Experiment 3442
 
  • V. Litvinenko, S.A. Belomestnykh, I. Ben-Zvi, J. Bengtsson, A.V. Fedotov, Y. Hao, D. Kayran, G.J. Mahler, W. Meng, T. Rao, T. Roser, B. Sheehy, R. Than, J.E. Tuozzolo, G. Wang, V. Yakimenko
    BNL, Upton, Long Island, New York, USA
  • G.I. Bell, D.L. Bruhwiler, V.H. Ranjbar, B.T. Schwartz
    Tech-X, Boulder, Colorado, USA
  • A. Hutton, G.A. Krafft, M. Poelker, R.A. Rimmer
    JLAB, Newport News, Virginia, USA
  • M.A. Kholopov, P. Vobly
    BINP SB RAS, Novosibirsk, Russia
  
  Co­her­ent elec­tron cool­ing (CEC) is con­sid­ered to be on of po­ten­tial can­di­dates ca­pa­ble of cool­ing high-en­er­gy, high-in­ten­si­ty hadron beams to very small emit­tances. It also has a po­ten­tial to sig­nif­i­cant­ly boost lu­mi­nos­i­ty of high-en­er­gy hadron-hadron and elec­tron-hadron col­lid­ers. In a CEC sys­tem, a per­tur­ba­tion of the elec­tron den­si­ty caused by a hadron is am­pli­fied and fed back to the hadrons to re­duce the en­er­gy spread and the emit­tance of the beam. Fol­low­ing the fund­ing de­ci­sion by DoE of­fice of Nu­cle­ar Physics, we are de­sign­ing and build­ing co­her­ent elec­tron cool­er for a proof-of-prin­ci­ple ex­per­i­ment at RHIC to cool 40 GeV heavy ion beam. In this paper, we de­scribe the lay­out of the CeC in­stalled into IP2 in­ter­ac­tion re­gion at RHIC. We pre­sent the de­sign of the CeC cool­er and re­sults of pre­lim­i­nary sim­u­la­tions.  
 
THPZ020 eRHIC Interaction Region Design 3729
 
  • D. Trbojevic, J. Beebe-Wang, Y. Hao, D. Kayran, Y. Luo, V. Ptitsyn, N. Tsoupas
    BNL, Upton, Long Island, New York, USA
  • V. Litvinenko
    Stony Brook University, Stony Brook, USA
  
  Funding: *Work performed under a Contract Number DE-AC02-98CH10886 with the auspices of the US Department of Energy.
In­ter­ac­tion re­gion de­sign of the fu­ture elec­tron ion col­lid­er at Rel­a­tivis­tic Heavy Ion Col­lid­er (eRHIC) is pre­sent­ed. Po­lar­ized pro­tons/He­li­um and heavy ions will col­lid­er with 5-30 GeV po­lar­ized elec­trons with a 10 mrad angle by using the crab cav­i­ty cross­ing. The in­ter­ac­tion re­gion is de­signed with­out bend­ing elec­trons to avoid prob­lems with syn­chrotron ra­di­a­tion. Use of the com­bined func­tion mag­net in the ion side al­lows de­tec­tion of neu­trons. De­sign al­lows de­tec­tion of deep vir­tu­al scat­ter­ing as well as de­tec­tion of par­tons with lower en­er­gies (po/2.5). The be­ta­tron func­tion at col­li­sions is 5 cm as­sum­ing use of three di­men­sion­al elec­tron beam cool­ing. Spe­cial chro­matic­i­ty cor­rec­tion is ap­plied in both sides of the ion straight sec­tion in­ter­ac­tion re­gion. Elec­trons ar­rive with avoid­ing com­plete­ly syn­chrotron ra­di­a­tion at the de­tec­tor. Spe­cial su­per­con­duct­ing com­bined func­tion mag­net is de­signed to allow pas­sage of elec­trons through the field free re­gion. 		 
 
THPZ019 High Luminosity Electron-hadron Collider eRHIC 3726
 
  • V. Ptitsyn, E.C. Aschenauer, J. Beebe-Wang, S.A. Belomestnykh, I. Ben-Zvi, R. Calaga, X. Chang, A.V. Fedotov, H. Hahn, L.R. Hammons, Y. Hao, P. He, A.K. Jain, E.C. Johnson, D. Kayran, J. Kewisch, V. Litvinenko, G.J. Mahler, W. Meng, B. Parker, A.I. Pikin, T. Rao, T. Roser, B. Sheehy, J. Skaritka, R. Than, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, Q. Wu, W. Xu
    BNL, Upton, Long Island, New York, USA
  
  We pre­sent the de­sign of a fu­ture high-en­er­gy high-lu­mi­nos­i­ty elec­tron-hadron col­lid­er at RHIC called eRHIC. We plan adding 20 (30) GeV en­er­gy re­cov­ery linacs to ac­cel­er­ate and to col­lide po­lar­ized and un­po­lar­ized elec­trons with hadrons in RHIC. The cen­ter-of-mass en­er­gy of eRHIC will range from 30 to 200 GeV. The lu­mi­nos­i­ty ex­ceed­ing 1034 cm-2s−1 can be achieved in eRHIC using the low-be­ta in­ter­ac­tion re­gion which a 10 mrad crab cross­ing. A nat­u­ral stag­ing sce­nario of step-by-step in­creas­es of the elec­tron beam en­er­gy by bui­lid­ing-up of eRHIC's SRF linacs. We re­port on the eRHIC de­sign and cost es­ti­mates for it stages. We dis­cuss the progress of eRHC R&D pro­jects from the po­lar­ized elec­tron source to the co­her­ent elec­tron cool­ing.