# Dissertation/Thesis Abstract

Probing the Spin Structure of the Proton Using Polarized Proton-Proton Collisions and the Production of W Bosons
by Beaumier, Michael John, Ph.D., University of California, Riverside, 2016, 385; 10181454
Abstract (Summary)

This thesis discusses the process of extracting the longitudinal asymmetry, $A_L {W\pm}$, describing $W\rightarrow\mu$ production in forward kinematic regimes. This asymmetry is used to constrain our understanding of the polarized parton distribution functions characterizing $\bar{u}$ and $\bar{d}$ sea quarks in the proton. This asymmetry will be used to constrain the overall contribution of the sea-quarks to the total proton spin. The asymmetry is evaluated over the pseudorapidity range of the PHENIX Muon Arms, $2.1 < |\eta|2.6$, for longitudinally polarized proton-proton collisions at 510 GeV $\sqrt{s}$. In particular, I will discuss the statistical methods used to characterize real muonic $W$ decays and the various background processes is presented, including a discussion of likelihood event selection and the Extended Unbinned Maximum Likelihood fit. These statistical methods serve estimate the yields of $W$ muonic decays, which are used to calculate the longitudinal asymmetry.

Indexing (document details)
 Advisor: Barish, Kenneth Commitee: Ellison, John, Seto, Richard School: University of California, Riverside Department: Physics School Location: United States -- California Source: DAI-B 78/03(E), Dissertation Abstracts International Source Type: DISSERTATION Subjects: Physics, Nuclear physics, Particle physics Keywords: Nucleon spin physics, Phenix, Proton spin, Rhic, Sea quark polarization, Weak interaction Publication Number: 10181454 ISBN: 9781369300390