Speaker
Description
Over the last two decades, the PHENIX experiment has utilized the polarized proton collisions delivered at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory to study spin structure and dynamics in high energy nuclear physics. Measurements of longitudinal spin asymmetries in direct photons and light mesons revealed the important contribution of gluon polarization to the proton spin while the longitudinal spin asymmetry of W bosons helped uncover a nonzero polarized sea quark asymmetry. Transverse spin asymmetries at central rapidity of direct photons, light mesons, and open heavy flavor provided significant constraints on spin-momentum correlations between protons and their constituent gluons. At forward rapidity, large transverse spin asymmetries of charged hadrons and light mesons highlighted the substantial impact of the initial- and final-state quark-gluon correlation functions. Nuclear effects in spin physics were also studied through measurements of transverse spin asymmetries from transversely polarized $p^{\uparrow}+A$ collisions. While little impact is seen at central rapidity, large nuclear effects observed at forward rapidity remain a mystery phenomenologically. In this presentation, I will discuss these recent highlights of spin physics from PHENIX and how they help inform our understanding of the field.
