Analysis of low energy AGS polarimeter data and potential consequences for RHIC spin physics.

Cadman, R. ; Krueger, K. ; Spinka, H. ; Underwood, D. ; Yokosawa, A. ; Huang, H.

Argonne National Laboratory

关键词: 43 Particle Accelerators;    Targets;    Impurities;    Asymmetry;    Polarimeters;   

DOI  :  10.2172/785377
RP-ID  :  ANL-HEP-TR-01-36
RP-ID  :  W-31-109-ENG-38
RP-ID  :  785377

美国|英语

来源: UNT Digital Library

【 摘 要 】

The small asymmetries measured at G{sub {gamma}} = 7.5 during the RHIC spin commissioning were a serious concern. In earlier runs, asymmetries double those from the spin commissioning time (September 2000) had sometimes been observed, and there had been few changes to the AGS polarimeter hardware or operating conditions. Recently, the observed changes in the asymmetries measured at G{sub {gamma}} = 7:5 have been ascribed to contamination of the carbon target asymmetry with that from the fishline target and vice-versa, because of the sizeable beam spot size compared to the separation of the targets. This note addresses this hypothesis using the observed asymmetries. This problem could directly impact spin physics at RHIC.