Exploring gluon polarization in the proton with STAR Conference Paper uri icon

abstract

  • One of the primary goals of the RHIC spin program is to determine the gluon polarization distribution within the proton. pp collisions involve a mixture of quark-quark, quark-gluon, and gluon-gluon scattering. In RHIC kinematics, the quark-gluon and gluon-gluon contributions dominate, which makes RHIC an ideal tool to explore gluon polarization. The STAR experiment hasmeasured the longitudinal double-spin asymmetry, A LL, in √s=200 GeV pp collisions for a broad range of inclusive and correlated final states. The inclusive measurements provide valuable constraints on the gluon polarization in the proton when included in a next-to-leading-order global analysis. At leading order, the correlation measurements provide access to the incident parton kinematics, allowing a direct determination of the momentum dependence of the gluon polarization, Δg(x,Q 2). Recent STAR results are described, and the anticipated sensitivity of upcoming measurements at s=200 GeV is discussed. © 2012 American Institute of Physics.

author list (cited authors)

  • Gagliardi, C. A., & Collaboration, S.

publication date

  • January 1, 2012 11:11 AM

publisher

  • AIP  Publisher