Double-spin asymmetry of electrons from heavy-flavor decays in p+p collisions at √s=200  GeV

Abstract

We report on the first measurement of the double-spin asymmetry, ALL, of electrons from the decays of hadrons containing heavy flavor in longitudinally polarized p+p collisions at √s=200  GeV for pT=0.5 to 3.0  GeV/c. The asymmetry was measured at midrapidity (|η|<0.35) with the PHENIX detector at the Relativistic Heavy Ion Collider. The measured asymmetries are consistent with zero within the statistical errors. We obtained a constraint for the polarized gluon distribution in the proton of |Δg/g(log10x=−1.6+0.5−0.4,μ=mcT)|2<0.030 (1σ) based on a leading-order perturbative quantum chromodynamics model, using the measured asymmetry.