| The separate contributions of u, d, u and d quarks to the proton spin are at present known only from lepton semi-inclusive deep inelastic scattering (SIDIS) double spin asymmetries. Single spin asymmetries of leptons from W bosons produced in longitudinally polarized pp collisions are directly sensitive to the quark polarizations [1]. The PHENIX collaboration at RHIC plans to determine the W+ and W - boson production cross sections and single spin asymmetries at s = 500 GeV by detecting decay muons at forward and backward rapidities. In order to understand the effects of resolution, backgrounds, and efficiency on the physics measurements, the PHENIX spectrometer simulation PISA was used to study the planned measurements and determine realistic expectations of the yields and the sensitivity to the light quark polarizations. |
