Unpolarized cross sections and double-helicity asymmetries of single-inclusive positive and negative charged hadrons at midrapidity from p+p collisions at √s=62.4GeV are presented. The PHENIX measurement of the cross sections for 1.0<p T<4.5GeV/c are consistent with perturbative QCD calculations at next-to-leading order in the strong-coupling constant, α s. Resummed pQCD calculations including terms with next-to-leading-log accuracy, yielding reduced theoretical uncertainties, also agree with the data. The double-helicity asymmetry, sensitive at leading order to the gluon polarization in a momentum-fraction range of 0.05x gluon 0.2, is consistent with recent global parametrizations disfavoring large gluon polarization.
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - 8 Nov 2012|
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)