AGS P-carbon CNI polarimeter Operation Experience

Abstract

The p-carbon polarimeter working in the dp/p Coulomb Nuclear Interference (CNI) region has been used in the Brookhaven Alternating Gradient Synchrotron (AGS) for many years. It has gone though several upgrades to improve its performance. With targets sweeping through beam vertically and horizontally, the polarimeter can provide polarization profile information. To preserve polarization, a pair of horizontal tune jump quads have been used to overcome horizontal intrinsic resonances. Recently, the polarization measurement on the energy ramp has been used to decide the beam energy as function of time on the ramp. This paper summarize the recent operation experience of AGS p-carbon CNI polarimeter.

Absolute polarization measurement of the 200 MeV proton beam at BNL Linac.

“…Therefore, the polarimetry is an essential component of the polarized collider facility. A complete set of polarimeters includes: Lamb-shift polarimeter at the source energy, a 200 MeV polarimeter [2] after the linac, and polarimeters in AGS and RHIC based on proton-Carbon scattering in Coulomb-Nuclear Interference region [3]. A polarized hydrogen jet polarimeter (HJET) was used for the absolute polarization measurements in RHIC [4].…”