Author: Meng, W.
Paper Title Page
TUP147 Rotating Dipole and Quadrupole Field for a Multiple Cathode System 1106
 
  • X. Chang, I. Ben-Zvi, J. Kewisch, V. Litvinenko, W. Meng, A.I. Pikin, V. Ptitsyn, T. Rao, B. Sheehy, J. Skaritka, Q. Wu
    BNL, Upton, Long Island, New York, USA
  • E. Wang
    PKU/IHIP, Beijing, People's Republic of China
  • T. Xin
    Stony Brook University, Stony Brook, USA
 
  A multiple cathode system has been designed to provide the high average current polarized electron bunches for the future electron-ion collider eRHIC. One of the key research topics in this design is the technique to generate a combined dipole and quadrupole rotating field at high frequency (700 kHz). This type of field is necessary for combining bunches from different cathodes to the same axis with minimum emittance growth. Our simulations and the prototype test results to achieve this will be presented.  
 
THP064 The Dipole Corrector Magnets for the RHIC Fast Global Orbit Feedback System 2249
 
  • P. Thieberger, L. Arnold, C. Folz, R.L. Hulsart, A.K. Jain, R. Karl, G.J. Mahler, W. Meng, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, V. Ptitsyn, J. Ritter, L. Smart, J.E. Tuozzolo, J. White
    BNL, Upton, Long Island, 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 recently completed RHIC fast global orbit feedback system uses 24 small “window-frame” horizontal dipole correctors. Space limitations dictated a very compact design. The magnetic design and modelling of these laminated yoke magnets is described as well as the mechanical implementation, coil winding, vacuum impregnation, etc. Test procedures to determine the field quality and frequency response are described. The results of these measurements are presented and discussed. A small fringe field from each magnet, overlapping the opposite RHIC ring, is compensated by a correction winding placed on the opposite ring’s magnet and connected in series with the main winding of the first one. Results from measurements of this compensation scheme are shown and discussed.
 
 
MOP268 RHIC 10 Hz Global Orbit Feedback System 609
 
  • R.J. Michnoff, L. Arnold, C. Carboni, P. Cerniglia, A.J. Curcio, L. DeSanto, C. Folz, C. Ho, L.T. Hoff, R.L. Hulsart, R. Karl, C. Liu, Y. Luo, W.W. MacKay, G.J. Mahler, W. Meng, K. Mernick, M.G. Minty, C. Montag, R.H. Olsen, J. Piacentino, P. Popken, R. Przybylinski, V. Ptitsyn, J. Ritter, R.F. Schoenfeld, P. Thieberger, J.E. Tuozzolo, A. Weston, J. White, P. Ziminski, P. Zimmerman
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Vibrations of the cryogenic triplet magnets at the Relativistic Heavy Ion Collider (RHIC) are suspected to be causing the beam perturbations observed at frequencies around 10 Hz. Several solutions to counteract the effect have been considered in the past, including reinforcing the magnet base support assembly, a mechanical servo feedback system, and a local beam feedback system at each of the two experimental areas. However, implementation of the mechanical solutions would be expensive, and the local feedback system was insufficient since perturbation amplitudes outside the experimental areas were still problematic. A global 10 Hz orbit feedback system is currently under development at RHIC consisting of 36 beam position monitors (BPMs) and 12 small dedicated dipole corrector magnets in each of the two counter-rotating rings. A subset of the system consisting of 8 BPMs and 4 corrector magnets in each ring was installed and successfully tested during the RHIC 2010 run; and the complete system is being installed for the 2011 run. A description of the overall system architecture and results with beam will be discussed.
 
 
TUOAN2 High Luminosity Electron-Hadron Collider eRHIC 693
 
  • V. Ptitsyn, E.C. Aschenauer, M. Bai, J. Beebe-Wang, S.A. Belomestnykh, I. Ben-Zvi, M. Blaskiewicz, R. Calaga, X. Chang, A.V. Fedotov, H. Hahn, L.R. Hammons, Y. Hao, P. He, W.A. Jackson, A.K. Jain, E.C. Johnson, D. Kayran, J. Kewisch, V. Litvinenko, G.J. Mahler, G.T. McIntyre, W. Meng, M.G. Minty, B. Parker, A.I. Pikin, T. Rao, T. Roser, B. Sheehy, J. Skaritka, S. Tepikian, R. Than, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, Q. Wu, W. Xu, A. Zelenski
    BNL, Upton, Long Island, New York, USA
  • E. Pozdeyev
    FRIB, East Lansing, Michigan, USA
  • E. Tsentalovich
    MIT, Middleton, Massachusetts, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We present the design of future high-energy high-luminosity electron-hadron collider at RHIC called eRHIC. We plan on adding 20 (potentially 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-2 s-1 can be achieved in eRHIC using the low-beta interaction region with a 10 mrad crab crossing. We report on the progress of important eRHIC R&D such as the high-current polarized electron source, the coherent electron cooling and the compact magnets for recirculating passes. A natural staging scenario of step-by-step increases of the electron beam energy by builiding-up of eRHIC's SRF linacs and a potential of adding polarized positrons are also presented.
 
slides icon Slides TUOAN2 [4.244 MB]  
 
THOBN3 Proof-of-Principle Experiment for FEL-based Coherent Electron Cooling 2064
 
  • V. Litvinenko, I. Ben-Zvi, J. Bengtsson, A.V. Fedotov, Y. Hao, D. Kayran, G.J. Mahler, W. Meng, T. Roser, B. Sheehy, R. Than, J.E. Tuozzolo, G. Wang, S.D. Webb, V. Yakimenko
    BNL, Upton, Long Island, New York, USA
  • G.I. Bell, D.L. Bruhwiler, B.T. Schwartz
    Tech-X, Boulder, Colorado, USA
  • A. Hutton, G.A. Krafft, M. Poelker, R.A. Rimmer
    JLAB, Newport News, Virginia, USA
 
  Funding: This work is supported the U.S. Department of Energy
Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron-hadron and electron-hadron colliders*. In a CEC system, a hadron beam interacts with a cooling electron beam. A perturbation of the electron density caused by ions is amplified and fed back to the ions to reduce the energy spread and the emittance of the ion beam. To demonstrate the feasibility of CEC we propose a proof-of-principle experiment at RHIC using one of JLab’s SRF cryo-modules. In this paper, we describe the experimental setup for CeC installed into one of RHIC's interaction regions. We present results of analytical estimates and results of initial simulations of cooling a gold-ion beam at 40 GeV/u energy via CeC.
* Vladimir N. Litvinenko, Yaroslav S. Derbenev, Physical Review Letters 102, 114801
 
slides icon Slides THOBN3 [1.379 MB]  
 
THP006 Status of High Current R&D Energy Recovery Linac at Brookhaven National Laboratory 2148
 
  • D. Kayran, Z. Altinbas, D.R. Beavis, I. Ben-Zvi, R. Calaga, D.M. Gassner, H. Hahn, L.R. Hammons, A.K. Jain, J.P. Jamilkowski, N. Laloudakis, R.F. Lambiase, D.L. Lederle, V. Litvinenko, G.J. Mahler, G.T. McIntyre, W. Meng, B. Oerter, D. Pate, D. Phillips, J. Reich, T. Roser, C. Schultheiss, B. Sheehy, T. Srinivasan-Rao, R. Than, J.E. Tuozzolo, D. Weiss, W. Xu, A. Zaltsman
    BNL, Upton, Long Island, New York, USA
 
  An ampere-class 20 MeV superconducting energy recovery linac (ERL) is under construction at Brookhaven National Laboratory (BNL) for testing of concepts relevant for high-energy coherent electron cooling and electron-ion colliders. One of the goals is to demonstrate an electron beam with high charge per bunch (~5 nC) and low normalized emittance (~5 mm-mrad) at an energy of 20 MeV. A flexible lattice for the ERL loop provides a test bed for investigating issues of transverse and longitudinal instabilities and diagnostics for CW beam. A superconducting 703 MHz RF photo-injector is considered as an electron source for such a facility. We will start with a straight pass (gun/cavity/beam stop) test for gun performance studies. Later, we will install and test a novel injection line concept for emittance preservation in a lower-energy merger. Here we present the status and our plans for construction and commissioning of this facility.