RHIC Performance with Polarized Protons in Run-6

Abstract

The RHIC polarized proton run (Run-6) in 2006 started on February 1 and continued for 21 weeks. The Run-6 included the machine operation at different beam energies and with different orientation of beam polarization at the collision points. The machine operation at lOOGeV and 31.2 GeV provided physics data of polarized proton collisions to the STAR, PHENIX and BRAHMS experiments. Record levels of the luminosity (up to 3.5.1031 cm-* s-' peak) and proton beam polarization (up to 65%) were achieved during the lOOGeV operation. The beam polarization was preserved during the acceleration by using Siberian Snakes, based on helical magnets. The polarization orientation at STAR and PHENIX experiments was controlled with helical spin rotators. During different stages of the run the physics data were provided with longitudinal, vertical and horizontal orientations of the beam polarization at the collision points. Total luminosity integrals of 45 pb-' at 100 GeV and 0.35 pb" at 3 1.2 GeV were delivered to the experiments.

Transverse beam transfer functions of colliding beams in RHIC

“…We have taken such BTF measurements of colliding proton beams during the RHIC Run-6 in 2006 [2], and compare the measured tune distributions with calculated ones.…”

RHIC plans towards higher luminosity

“…The design and achieved parameters are summarized in Table 1. The average proton polarization of 60% was achieved at store energy of 100 GeV [5]. Operation with polarized protons at 250 GeV is under development 161.…”

“…In the AGS, a warm and cold Siberian snakes were installed which helped to overcome this limit. The AGS cold snake was used for the first time operationally in 2006 run with polarized protons which lead to new polarization records in RHIC Following the vacuum upgrades, the dynamic pressure rise was overcome, and operation with 111 bunches became possible [5]. The main limitation is presently due to beam-beam effects and other non-linear and modulation driven effects.…”

Long-range beam-beam experiments in the Relativistic Heavy Ion Collider

“…The reader should note that this is an identical copy of an article first published in [1]. Beam-beam effects have limited the performance of previous and existing hadron colliders [2][3][4] such as the ISR [5,6], SppS [7][8][9][10], Tevatron [11][12][13] and RHIC [14,15], and are also expected to limit the performance of the LHC [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31].…”