A new relative proton polarimeter for RHIC

An innovative polarimeter based on proton carbon elastic scattering in the Coulomb nuclear interference (CNI) region has been installed and commissioned in the Blue ring of RHIC during the first RHIC polarized proton commissioning in September, 2000. The polarimeter consists of ultra-thin C targets and four Si detectors. All elements are in a 1.6 meter vacuum chamber. This paper summarizes the polarimeter design issues and recent commissioning results.