Prompt Photon A_N with the PHENIX MPC-EX Detector

TL;DR

This paper discusses the use of the PHENIX MPC-EX detector to measure the prompt photon single spin asymmetry A_N in polarized proton collisions, aiming to understand the proton spin structure.

Contribution

It introduces the MPC-EX detector extension and its application for measuring A_N in high-energy polarized proton collisions.

Findings

Potential to elucidate the correlation of valence parton transverse motion with proton spin.

Enhanced access to high-x partons in the proton.

Feasibility of measuring A_N with the new detector setup.

Abstract

The PHENIX MPC-EX detector is a Si-W preshower extension to the existing Muon Piston Calorimeters (MPC). Covering the pseudorapidity range 3.1 <eta < 3.8, the MPC-EX and MPC access high-x partons in the projectile nucleon The combined detectors will make possible a measurement of the prompt photon single spin asymmetry A_N in 200GeV transversely polarized p+p collisions, which will help elucidate the correlation of the transverse motion of valence partons in the proton with the proton spin.