Double Helicity Asymmetry in π⁰ Production at Midrapidity in Polarized p+p Collisions at √(s)=510 GeV

2017/01/19 by I. Yoon, Yoon, Inseok
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High-Energy Particle Collisions Research #Nuclear Experiment (nucl-ex) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions

paper · pdf · doi:10.48550/arxiv.1701.05261

openalex publication_date 2017/01/19 · openalex created_date 2024/04/11 · openalex updated_date 2026/07/28

Abstract

PHENIX measurements are presented for the cross-section and double-helicity asymmetry (A_LL) of inclusive π⁰ production (A_LL^π⁰) at midrapidity from p+p collisions at √(s)=510 GeV from data taken in 2012 and 2013 at the Relativistic Heavy Ion Collider (RHIC). The next-to-leading order (NLO) perturbative QCD (pQCD) calculation agrees excellently with the presented cross-section result. The A_LL^π⁰ follows an increasingly positive asymmetry as functions of p_T and √(s) at the fixed x_T. The latest global analysis results, which support the positive spin contribution of gluon (ΔG), agrees excellently with the presented asymmetry result. The asymmetry result extends the experimental sensitivity to the previously unexplored x region down to x∼0.01 and provides additional constraints on ΔG.

Related

• Recent results from PHENIX on double helicity asymmetry (A_LL) measurement at √(s) = 510 GeV
• Recent PHENIX Results on pi+, pi-, and eta Production in polarized pp Collisions at RHIC at sqrt(s) = 200 GeV
• Transverse single spin asymmetry for very forward π⁰ production in polarized proton-proton collisions at √(s) = 510 GeV
• Measurement of transverse-single-spin asymmetries for midrapidity and forward-rapidity production of hadrons in polarized p+p collisions at √(s)=200 and 62.4 GeV
• Longitudinal double helicity asymmetry A_LL from direct photon, jet and charged pion production in polarized p+p collisions