Recent STAR results in high-energy polarized proton-proton collisions at RHIC

TL;DR

The STAR experiment at RHIC investigates the spin structure of the proton through high-energy polarized proton collisions, measuring processes like jet, hadron, and W boson production to understand gluon polarization and spin-flavor dynamics.

Contribution

This paper presents recent experimental results from STAR on jet, hadron, and W boson production in polarized proton collisions, advancing the understanding of proton spin structure.

Findings

Measurement of jet and hadron production at 200 GeV.

First results on W boson production in polarized collisions.

Insights into gluon polarization and spin-flavor structure.

Abstract

The STAR experiment at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory is carrying out a spin physics program in high-energy polarized $\vec{p}+\vec{p}$ collisions at $\sqrt{s}=200-500\,$GeV to gain a deeper insight into the spin structure and dynamics of the proton. One of the main objectives of the spin physics program at RHIC is the extraction of the polarized gluon distribution function based on measurements of gluon initiated processes, such as hadron and jet production. The STAR detector is well suited for the reconstruction of various final states involving jets, $\pi^{0}$, $\pi^{\pm}$, e$^{\pm}$ and $\gamma$, which allows to measure several different processes. Recent results will be shown on the measurement of jet production and hadron production at $\sqrt{s}=200\,$GeV. The RHIC spin physics program has recently completed the first data taking period in 2009 of polarized $\vec{p}+\vec{p}$ collisions at $\sqrt{s}=500\,$GeV. This opens a new era in the study of the spin-flavor structure of the proton based on the production of $W^{-(+)}$ bosons. Recent STAR results on the first measurement of $W$ boson production in polarized $\vec{p}+\vec{p}$ collisions will be shown.