Speaker
Young Jin Kim
(University of Illinois at Urbana-Champaign)
Description
A major direction of the physics program at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is to explore the origin of proton spin structure. Parity violating single spin asymmetries, $A_L$, for $W$-bosons in longitudinally polarized $p + p$ collisions at a center of mass energy of $\sqrt{s}$ = 500 GeV will give access to the flavor separated quark and anti-quark polarization distributions for up- and down-quarks in the proton.
The PHENIX collaboration has measured $A_L$ for electrons from $W$-decay in the central rapidity region, $-0.35 < \eta < 0.35$ based on a data sample taken in 2009. A second data sample taken in 2011 is being used to measure $A_L$ for $W$-decays into muons with two PHENIX forward muon spectrometers covering $1.2 < |\eta| < 2.4$. Cross sections for $W^\pm$-boson production at central rapidity and the corresponding single spin asymmetries will be presented. The cross sections will be compared with similar measurements at LHC. The upgrade effort directed at $W$-physics in the muon spectrometers just has been completed. The new instrumentation will be briefly described and the the status of the $W$-analysis in the PHENIX muon spectrometers will be discussed.
Primary author
Young Jin Kim
(University of Illinois at Urbana-Champaign)
