Author: Liu, C.
Paper Title Page
TUYB103 Status and Plans for the Polarized Hadron Collider at RHIC 1106
 
  • M. Bai, L. A. Ahrens, E.C. Aschenauer, G. Atoian, J. Beebe-Wang, M. Blaskiewicz, J.M. Brennan, K.A. Brown, D. Bruno, R. Connolly, T. D'Ottavio, K.A. Drees, Y. Dutheil, O. Eyser, W. Fischer, C.J. Gardner, J.W. Glenn, X. Gu, M. Harvey, T. Hayes, H. Huang, R.L. Hulsart, A.I. Kirleis, J.S. Laster, C. Liu, Y. Luo, Y. Makdisi, G.J. Marr, A. Marusic, F. Méot, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, S. Nemesure, P.H. Pile, A. Poblaguev, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, T. Roser, W.B. Schmidke, V. Schoefer, F. Severino, T.C. Shrey, D. Smirnov, K.S. Smith, D. Steski, S. Tepikian, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, M. Wilinski, K. Yip, A. Zaltsman, A. Zelenski, K. Zeno, S.Y. Zhang
    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.
As the world’s only high energy polarized proton collider, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) has been providing collisions of polarized proton beams at beam energy from 100~GeV to 255~GeV for the past decade to explore the proton spin structure as well as other spin dependent measurements. With the help of two Siberian Snakes per accelerator plus outstanding beam control, beam polarization is preserved up to 100~GeV. About 10% polarization loss has been observed during the acceleration between 100~GeV and 255~GeV due to several strong depolarizing resonances. Moderate polarization loss was also observed during a typical 8 hour physics store. This presentation will overview the achieved performance of RHIC, both polarization as well as luminosity. The plan for providing high energy polarized He-3 collisions at RHIC will also be covered.
This work is on behalf of RHIC team.
 
slides icon Slides TUYB103 [12.854 MB]  
 
TUPFI076 First RHIC Collider Test Operation at 2.5GeV Beam Energy 1523
 
  • C. Montag, L. A. Ahrens, M. Bai, J. Beebe-Wang, I. Blackler, M. Blaskiewicz, J.M. Brennan, K.A. Brown, D. Bruno, R. Connolly, T. D'Ottavio, K.A. Drees, W. Fischer, C.J. Gardner, X. Gu, M. Harvey, T. Hayes, L.T. Hoff, H. Huang, R.L. Hulsart, J.S. Laster, C. Liu, Y. Luo, G.J. Marr, A. Marusic, F. Méot, K. Mernick, R.J. Michnoff, M.G. Minty, J. Morris, S. Nemesure, V.H. Ranjbar, G. Robert-Demolaize, T. Roser, V. Schoefer, F. Severino, T.C. Shrey, K.S. Smith, S. Tepikian, J.E. Tuozzolo, M. Wilinski, A. Zaltsman, K. Zeno, W. Zhang
    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.
To search for the critical point in the QCD phase diagram, RHIC needs to operate at a set of low gold beam energies between 2.5 and 20 GeV per nucleon. During run 12, first successful collider operation at the lowest energy of 2.5 GeV per nucleon was achieved. We present the challenges and achieved results, and discuss possible future upgrades and improvements.
 
 
TUPFI082 RHIC Performance for FY2012 Heavy Ion Run 1538
 
  • Y. Luo, J.G. Alessi, M. Bai, E.N. Beebe, J. Beebe-Wang, I. Blackler, M. Blaskiewicz, J.M. Brennan, K.A. Brown, D. Bruno, J.J. Butler, R. Connolly, T. D'Ottavio, K.A. Drees, A.V. Fedotov, W. Fischer, C.J. Gardner, D.M. Gassner, X. Gu, Y. Hao, M. Harvey, T. Hayes, L.T. Hoff, H. Huang, P.F. Ingrassia, J.P. Jamilkowski, N.A. Kling, M. Lafky, J.S. Laster, C. Liu, D. Maffei, Y. Makdisi, M. Mapes, G.J. Marr, A. Marusic, F. Méot, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, C. Naylor, S. Nemesure, A.I. Pikin, P.H. Pile, V. Ptitsyn, D. Raparia, G. Robert-Demolaize, T. Roser, P. Sampson, J. Sandberg, V. Schoefer, C. Schultheiss, F. Severino, T.C. Shrey, K.S. Smith, S. Tepikian, P. Thieberger, D. Trbojevic, J.E. Tuozzolo, B. Van Kuik, G. Wang, M. Wilinski, A. Zaltsman, K. Zeno, S.Y. Zhang, W. Zhang
    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.
In the 2012 RHIC heavy ion run, we collided 96.4~GeV U-U ions and 100~GeV Cu-Au ions for the first time in RHIC. The new pre-injector with the electron-beam ion source (EBIS) was used to provide ions for RHIC ion collisions for the first time. By adding the horizontal cooling, the powerful 3-D stochastic cooling largely enhanced the luminosity. With the double bunch merging in the Booster and AGS, the bunch intensities of Cu and Au ions in RHIC surpassed their projections. Both PHENIX and STAR detectors reached their integrated luminosity goals for the U-U and Cu-Au collisions. In this article we review the machine improvement and performance in this run.
 
 
TUPFI084 RHIC Polarized Proton Operation for 2013 1544
 
  • V.H. Ranjbar, L. A. Ahrens, E.C. Aschenauer, M. Bai, J. Beebe-Wang, M. Blaskiewicz, J.M. Brennan, K.A. Brown, D. Bruno, R. Connolly, T. D'Ottavio, K.A. Drees, Y. Dutheil, W. Fischer, C.J. Gardner, J.W. Glenn, X. Gu, M. Harvey, T. Hayes, H. Huang, R.L. Hulsart, A.I. Kirleis, J.S. Laster, C. Liu, Y. Luo, Y. Makdisi, G.J. Marr, A. Marusic, F. Méot, K. Mernick, R.J. Michnoff, M.G. Minty, C. Montag, J. Morris, S. Nemesure, P.H. Pile, A. Poblaguev, V. Ptitsyn, G. Robert-Demolaize, T. Roser, W.B. Schmidke, V. Schoefer, F. Severino, T.C. Shrey, D. Smirnov, K.S. Smith, D. Steski, S. Tepikian, D. Trbojevic, N. Tsoupas, J.E. Tuozzolo, G. Wang, M. Wilinski, K. Yip, A. Zaltsman, A. Zelenski, K. Zeno, S.Y. Zhang
    BNL, Upton, Long Island, New York, USA
  • O. Eyser
    UCR, Riverside, California, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The 2013 operation of the Relativistic Heavy Ion Collider (RHIC) marks the second year of running under the RHIC II era. Additionally this year saw the implementation of several important upgrades designed to push the intensity frontier. Two new E-lenses have been installed, along with a new lattice designed for the E-lens operation. A new polarized proton source which generates about factor of 2 more intensity was commissioned as well as a host of RF upgrades from a new longitudinal damper, Landau cavity in RHIC to a new low level RF and new harmonic structure for the AGS. We present an overview of the challenges and results from this years run.
 
 
TUPWO073 Precision Tune, Phase and Beta Function Measurement by Frequency Analysis in RHIC 2027
 
  • C. Liu, R.L. Hulsart, A. Marusic, R.J. Michnoff, M.G. Minty, P. Thieberger
    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 high quality of the RHIC turn-by-turn (TbT) data obtained from the beam position monitor (BPM) system was fully exploited by using two analysis approaches. One is a time domain least square fitting technique and the other one is a frequency domain interpolated Fourier Transform technique. Both methods were applied to 1024-turn data from kicked beam and from continuous coherent excitation experiments. The betatron phase precisions obtained with both methods were ~0.1 degree for the continuous excitation and ~0.2 degree for the impulse excitation. The algorithms of these two analyses and comparison of their results will be presented in this report.
 
 
TUPWO074 Reducing Spin Tune Spread by Matching DX Prime at Snakes in RHIC 2030
 
  • C. Liu, M. Bai, E.D. Courant, A. Marusic, M.G. Minty, V.H. Ranjbar, S. Tepikian, R.A. Thomas, D. Trbojevic
    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.
At the Relativistic Heavy Ion Collider (RHIC) at BNL the physics program includes collisions between beams of polarized protons at high beam energies. Maintaining the proton's polarization is vital and preserved primarily by application of a pair of Siberian snakes. Measurements from recent high-energy physics runs indicate polarization loss during acceleration between 100 and 250 GeV. Based on analytic estimations for off-momentum particles and/or beams, a nonzero difference in DX prime - the dispersion function angle - between the snakes can result in a shift in the spin tune, or equivalently, of the conditions of snake resonances in close proximity to the beam during acceleration. Requiring that DX prime at the two Siberian snakes in RHIC being equal would reduce the spin tune shift for off-energy particles so helping to maintain polarization during the energy ramp. Preservation of half-integer spin tune is also important for future operation of the spin flipper at store. In this report, the matching scheme and simulations using MAD-X will be presented together with a newly applied method based on response matrices.