Recent PHENIX Results on pi+, pi-, and eta Production in polarized pp Collisions at RHIC at sqrt(s) = 200 GeV

TL;DR

This paper reports recent measurements of double helicity asymmetries and cross sections for eta and charged pion production in polarized proton-proton collisions at RHIC, providing insights into the gluon spin contribution.

Contribution

It presents new experimental data on eta and pion production asymmetries and cross sections at 200 GeV, enhancing understanding of gluon polarization in protons.

Findings

Measured double helicity asymmetries for eta and pions.

Provided eta cross section and fragmentation functions.

Contributed to constraining gluon polarization models.

Abstract

Measurements of double helicity asymmetries for inclusive hadron production in polarized proton-proton collisions are sensitive to spin-dependent parton distribution functions, in particular to the gluon distribution function. This study focuses on double helicity asymmetries in eta and charged pion production at mid-rapidity, as well as on the eta cross section and fragmentation functions.