Transverse Single-Spin Asymmetries of Midrapidity Direct Photons and Neutral Mesons at PHENIX
Nicole Lewis
SciPost Phys. Proc. 8, 009 (2022) · published 11 July 2022
- doi: 10.21468/SciPostPhysProc.8.009
- Submissions/Reports
Proceedings event
28th Annual Workshop on Deep-Inelastic Scattering (DIS) and Related Subjects
Abstract
Results are presented for the transverse single-spin asymmetries of direct photons, neutral pions, and eta mesons for $|\eta|<0.35$ from $p^\uparrow + p$ collisions with $\sqrt{s} = 200$ GeV at PHENIX. As hadrons, $\pi^0$ and $\eta$ mesons are sensitive to both initial- and final-state effects and at midrapidity probe the dynamics of gluons along with a mix of quark flavors. Because direct photon production does not include hadronization, the direct photon TSSA is only sensitive to initial-state effects and at midrapidity provides a clean probe of the gluon dynamics in transversely polarized protons. All three of these results will help constrain the collinear twist-3 trigluon correlation function as well as the gluon Sivers function, improving our knowledge of spin-dependent gluon dynamics in QCD.