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تسجيل مستخدم جديدThe STAR W Program at RHIC
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Justin R. Stevens
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The production of $W$ bosons in polarized $p+p$ collisions at RHIC provides an excellent tool to probe the protons sea quark distributions. At leading order $W^{-(+)}$ bosons are produced in $bar{u}+d,(bar{d}+u)$ collisions, and parity-violating single-spin asymmetries measured in longitudinally polarized $p+p$ collisions give access to the flavor-separated light quark and antiquark helicity distributions. In this proceedings we report preliminary results for the single-spin asymmetry, $A_L$ from data collected in 2012 by the STAR experiment at RHIC with an integrated luminosity of 72 pb$^{-1}$ at $sqrt{s}=510$ GeV and an average beam polarization of 56%.
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This document summarizes recent achievements of the RHIC spin program and their impact on our understanding of the nucleons spin structure, i.e. the individual parton (quark and gluon) contributions to the helicity structure of the nucleon and to und
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