Author: Wang, E.
Paper Title Page
MOOHC2 The US Electron Ion Collider Accelerator Designs 1
 
  • A. Seryi, S.V. Benson, S.A. Bogacz, P.D. Brindza, M.W. Bruker, A. Camsonne, E. Daly, P. Degtiarenko, Y.S. Derbenev, M. Diefenthaler, J. Dolbeck, R. Ent, R. Fair, D. Fazenbaker, Y. Furletova, B.R. Gamage, D. Gaskell, R.L. Geng, P. Ghoshal, J.M. Grames, J. Guo, F.E. Hannon, L. Harwood, S. Henderson, H. Huang, A. Hutton, K. Jordan, D.H. Kashy, A.J. Kimber, G.A. Krafft, R. Lassiter, R. Li, F. Lin, M.A. Mamun, F. Marhauser, R. McKeown, T.J. Michalski, V.S. Morozov, P. Nadel-Turonski, E.A. Nissen, G.-T. Park, H. Park, M. Poelker, T. Powers, R. Rajput-Ghoshal, R.A. Rimmer, Y. Roblin, D. Romanov, P. Rossi, T. Satogata, M.F. Spata, R. Suleiman, A.V. Sy, C. Tennant, H. Wang, S. Wang, C. Weiss, M. Wiseman, W. Wittmer, R. Yoshida, H. Zhang, S. Zhang, Y. Zhang, Z.W. Zhao
    JLab, Newport News, Virginia, USA
  • D.T. Abell, D.L. Bruhwiler, I.V. Pogorelov
    RadiaSoft LLC, Boulder, Colorado, USA
  • E.C. Aschenauer, G. Bassi, J. Beebe-Wang, J.S. Berg, M. Blaskiewicz, A. Blednykh, J.M. Brennan, S.J. Brooks, K.A. Brown, K.A. Drees, A.V. Fedotov, W. Fischer, D.M. Gassner, W. Guo, Y. Hao, A. Hershcovitch, H. Huang, W.A. Jackson, J. Kewisch, A. Kiselev, V. Litvinenko, C. Liu, H. Lovelace III, Y. Luo, F. Méot, M.G. Minty, C. Montag, R.B. Palmer, B. Parker, S. Peggs, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, T. Roser, S. Seletskiy, V.V. Smaluk, K.S. Smith, S. Tepikian, P. Thieberger, D. Trbojevic, N. Tsoupas, E. Wang, W.-T. Weng, F.J. Willeke, H. Witte, Q. Wu, W. Xu, A. Zaltsman, W. Zhang
    BNL, Upton, New York, USA
  • D.P. Barber
    DESY, Hamburg, Germany
  • I.V. Bazarov
    Cornell University, Ithaca, New York, USA
  • G.I. Bell, J.R. Cary
    Tech-X, Boulder, Colorado, USA
  • Y. Cai, Y.M. Nosochkov, A. Novokhatski, G. Stupakov, M.K. Sullivan, C.-Y. Tsai
    SLAC, Menlo Park, California, USA
  • Z.A. Conway, M.P. Kelly, B. Mustapha, U. Wienands, A. Zholents
    ANL, Lemont, Illinois, USA
  • S.U. De Silva, J.R. Delayen, H. Huang, C. Hyde, S. Sosa, B. Terzić
    ODU, Norfolk, Virginia, USA
  • K.E. Deitrick, G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • D. Douglas
    Douglas Consulting, York, Virginia, USA
  • V.G. Dudnikov, R.P. Johnson
    Muons, Inc, Illinois, USA
  • B. Erdelyi, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  • J.D. Fox
    Stanford University, Stanford, California, USA
  • J. Gerity, T.L. Mann, P.M. McIntyre, N. Pogue, A. Sattarov
    Texas A&M University, College Station, USA
  • E. Gianfelice-Wendt, S. Nagaitsev
    Fermilab, Batavia, Illinois, USA
  • Y. Hao, P.N. Ostroumov, A.S. Plastun, R.C. York
    FRIB, East Lansing, Michigan, USA
  • T. Mastoridis
    CalPoly, San Luis Obispo, California, USA
  • J.D. Maxwell, R. Milner, M. Musgrave
    MIT, Cambridge, Massachusetts, USA
  • J. Qiang, G.L. Sabbi
    LBNL, Berkeley, California, USA
  • D. Teytelman
    Dimtel, Redwood City, California, USA
  • R.C. York
    NSCL, East Lansing, Michigan, USA
 
  With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collider, the prospects for construction of such a facility have taken a step forward. This paper provides an overview of the two site-specific EIC designs: JLEIC (Jefferson Lab) and eRHIC (BNL) as well as brief overview of ongoing EIC R&D.  
slides icon Slides MOOHC2 [14.774 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOOHC2  
About • paper received ※ 29 August 2019       paper accepted ※ 04 September 2019       issue date ※ 08 October 2019  
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MOPLM06 High Voltage Design of a 350 kV DC Photogun at BNL 102
 
  • W. Liu, O.H. Rahman, E. Wang
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Brookhaven National Laboratory is constructing a 350 kV DC high voltage photogun to provide spin-polarized electron beam for the proposed eRHIC facility. The photogun employs a compact inverted-tapered-geometry ceramic insulator that extends into the vacuum chamber and mechanically holds the cathode electrode. By operating at high voltage, the photogun will provide lower beam emittance, thereby improving the beam transmission through the injector apertures, and prolong the operating lifetime of the photogun. However, high voltage increases the field emission, which can result in high voltage breakdown and even lead to irreparable damage of the ceramic insulator. This work describes the methods to minimize the electric field near the metal-vacuum-insulator interface, and to avoid high voltage breakdown and ceramic insulator damage. The triple point junction shields are designed. The simulated electric field, field emission and beam transportation will be presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLM06  
About • paper received ※ 19 August 2019       paper accepted ※ 31 August 2019       issue date ※ 08 October 2019  
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MOPLH02 Study of Photocathode Surface Damage due to Ion Back-Bombardment in High Current DC Gun 174
SUPLE16   use link to see paper's listing under its alternate paper code  
 
  • J.P. Biswas
    Stony Brook University, Stony Brook, USA
  • O.H. Rahman, E. Wang
    BNL, Upton, New York, USA
 
  Funding: This work was supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704, with the U.S. DOE
In high current DC gun, GaAs photocathode lifetime is limited by the ion back-bombardment. While gun operation ions are generated and accelerate back towards the cathode thus remove the activation layer’s material Cesium from the photocathode surface. We have developed an object-oriented code to simulate the ion generation due to dynamic gas pressure and ion trace in the electromagnetic field. The pressure profile varies from cathode position towards the transfer line behind the anode, which signifies the importance of dynamic simulation for ion back-bombardment study. In our surface damage study, we traced the energy and position of the ions on the photocathode surface and performed the Stopping and Range of Ions in Matter(SRIM) simulation to count the number of Cesium atoms removed from the surface due to single bunch impact. Cesium atom removal is directly related to the photocathode Quantum Efficiency(QE) decay. Our new dynamic simulation code can be used in any DC gun to study ion back-bombardment. We have used this new code to better understand the ion generation in prototype BNL 350 KV DC gun, and we have also estimated the normalized QE decay due to ion back-bombardment.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLH02  
About • paper received ※ 27 August 2019       paper accepted ※ 03 September 2019       issue date ※ 08 October 2019  
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TUZBA1 Commissioning of the Electron Accelerator LEReC for Bunched Beam Cooling 330
 
  • D. Kayran, Z. Altinbas, D. Bruno, M.R. Costanzo, K.A. Drees, A.V. Fedotov, W. Fischer, M. Gaowei, D.M. Gassner, X. Gu, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, Y.C. Jing, J. Kewisch, C.J. Liaw, C. Liu, J. Ma, K. Mernick, T.A. Miller, M.G. Minty, L.K. Nguyen, M.C. Paniccia, I. Pinayev, V. Ptitsyn, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, L. Smart, K.S. Smith, A. Sukhanov, P. Thieberger, J.E. Tuozzolo, E. Wang, G. Wang, W. Xu, A. Zaltsman, H. Zhao, Z. Zhao
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The brand-new state of the art electron accelerator, LEReC, was built and commissioned at BNL. LEReC accelerator includes a photocathode DC gun, a laser system, a photocathode delivery system, magnets, beam diagnostics, a SRF booster cavity, and a set of Normal Conducting RF cavities to provide sufficient flexibility to tune the beam in the longitudinal phase space. Electron beam quality suitable for cooling in the Relativistic Heavy Ion Collider (RHIC) was achieved [1], which lead to the first demonstration of bunched beam electron cooling of hadron beams [2]. This presentation will discuss commissioning results, achieved beam parameters and performance of the LEReC systems.
[1] D.Kayran et al., First results from Commissioning of LEReC, in Proc of IPAC2019
[2] A.Fedotov et al., First electron cooling of hadron beams using a bunched electron beam, presented at NAPAC2019
 
slides icon Slides TUZBA1 [18.343 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUZBA1  
About • paper received ※ 27 August 2019       paper accepted ※ 31 August 2019       issue date ※ 08 October 2019  
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TUPLH24 Performance of CeC PoP Accelerator 526
 
  • I. Pinayev, Z. Altinbas, J.C. Brutus, A.J. Curcio, A. Di Lieto, T. Hayes, R.L. Hulsart, P. Inacker, Y.C. Jing, V. Litvinenko, J. Ma, G.J. Mahler, M. Mapes, K. Mernick, K. Mihara, T.A. Miller, M.G. Minty, G. Narayan, I. Petrushina, F. Severino, K. Shih, Z. Sorrell, J.E. Tuozzolo, E. Wang, G. Wang, A. Zaltsman
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Coherent electron cooling experiment is aimed for demonstration of the proof-of-principle demonstration of reduction energy spread of a single hadron bunch circulating in RHIC. The electron beam should have the required parameters and its orbit and energy should be matched to the hadron beam. In this paper we present the achieved electron beam parameters including emittance, energy spread, and other critical indicators. The operational issues as well as future plans are also discussed.
 
poster icon Poster TUPLH24 [11.180 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-TUPLH24  
About • paper received ※ 29 August 2019       paper accepted ※ 03 September 2019       issue date ※ 08 October 2019  
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THZBA5 First Electron Cooling of Hadron Beams Using a Bunched Electron Beam 957
 
  • A.V. Fedotov, Z. Altinbas, M. Blaskiewicz, J.M. Brennan, D. Bruno, J.C. Brutus, M.R. Costanzo, K.A. Drees, W. Fischer, J.M. Fite, M. Gaowei, D.M. Gassner, X. Gu, J. Halinski, K. Hamdi, L.R. Hammons, T. Hayes, R.L. Hulsart, P. Inacker, J.P. Jamilkowski, Y.C. Jing, P.K. Kankiya, D. Kayran, J. Kewisch, D. Lehn, C.J. Liaw, C. Liu, J. Ma, G.J. Mahler, M. Mapes, A. Marusic, K. Mernick, C. Mi, R.J. Michnoff, T.A. Miller, M.G. Minty, S.K. Nayak, L.K. Nguyen, M.C. Paniccia, I. Pinayev, S. Polizzo, V. Ptitsyn, T. Rao, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, L. Smart, K.S. Smith, H. Song, A. Sukhanov, R. Than, P. Thieberger, S.M. Trabocchi, J.E. Tuozzolo, P. Wanderer, E. Wang, G. Wang, D. Weiss, B.P. Xiao, T. Xin, W. Xu, A. Zaltsman, H. Zhao, Z. Zhao
    BNL, Upton, New York, USA
 
  Funding: Work supported by the U.S. Department of Energy.
The Low Energy RHIC electron Cooler (LEReC) was recently constructed and commissioned at BNL. The LEReC is the first electron cooler based on the RF acceleration of electron bunches (previous electron coolers all used DC beams). Bunched electron beams are necessary for cooling hadron beams at high energies. The challenges of such an approach include generation of electron beams suitable for cooling, delivery of electron beams of the required quality to the cooling sections without degradation of beam emittances and energy spread, achieving required small angles between electrons and ions in the cooling sections, precise energy matching between the two beams, high-current operation of the electron accelerator, as well as several physics effects related to bunched beam cooling. Following successful commissioning of the electron accelerator in 2018, the focus of the LEReC project in 2019 was on establishing electron-ion interactions and demonstration of cooling process using electron energy of 1.6MeV (ion energy of 3.85GeV/n), which is the lowest energy of interest. Here we report on the first demonstration of Au ion cooling in RHIC using this new approach.
 
slides icon Slides THZBA5 [16.417 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-THZBA5  
About • paper received ※ 16 August 2019       paper accepted ※ 31 August 2019       issue date ※ 08 October 2019  
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