Local Polarimetry for Proton Beams with the STAR Beam Beam Counters

Abstract

STAR collected data in proton-proton collisions at sqrt(s)=200 GeV with transverse and longitudinal beam polarizations during the 2003 running period at RHIC. We present preliminary results on single transverse spin asymmetries A_N in the production of forward charged hadrons detected with the Beam-Beam Counters (BBC). The asymmetries A_N measured at pseudorapidities 3.9 < |eta| < 5.0 are found to be of the order of 0.01 while asymmetries measured at smaller pseudorapidities 3.4 < |eta| < 3.9 are found to be consistent with zero. The BBC and its associated scaler system for fast data recording provides the first local polarimeter at STAR. The setup has been sucessfully used to tune the spin rotator magnets and to verify longitudinal polarization at STAR.

5 pages, 4 figures; contribution to the Proceedings of the 16th International Spin Physics Symposium, October 11-16, 2004, ICTP, Trieste, Italy

Cited by in corpus (5)

• The Spin Structure of the Nucleon
• Measurement of transverse single-spin asymmetries of ${\pi }^0$ and electromagnetic jets at forward rapidity in 200 and 500 GeV transversely polarized proton-proton collisions
• Comparison of transverse single-spin asymmetries for forward ${\pi }^0$ production in polarized $pp$, $p\mathrm{Al}$ and $p\mathrm{Au}$ collisions at nucleon pair c.m. energy $\sqrt{s_{\mathrm{NN}}}=200$ GeV
• Longitudinal double spin asymmetry in jet production at STAR
• Longitudinal spin transfer of Lambda and anti-Lambda in polarized pp collisions at \sqrt s=200 GeV at STAR