Spin Dependence in Polarized pC → pC Scattering at Low Momentum Transfer and Polarimetry at RHIC

Preliminary results from the ’03 RHIC Proton Spin Run on the spin dependence in the elastic scatterring of polarized protons off a carbon target at very low momentum transfer (0.005 < |t| < 0.05 GeV2/c2) are presented and discussed. Proton polarimeters based on this process are used in RHIC and AGS to measure reliably and in very short times the polarization of the proton beams. Polarimetry results from the just completed RHIC polarized proton run are also presented.