Inclusive cross section and double helicity asymmetry for pi(0) production in p plus p collisions at root s=62.4 GeV (Article No. 012003)
Abstract
The PHENIX experiment presents results from the RHIC 2006 run with polarized p p collisions at root s = 62.4 GeV, for inclusive pi(0) production at midrapidity. Unpolarized cross section results are measured for transverse momenta p(T) = 0.5 to 7 GeV/c.
Next-to-leading order perturbative quantum chromodynamics calculations are compared with the data, and while the calculations are consistent with the measurements, next-to-leading logarithmic corrections improve the agreement. Double helicity asymmetries A(LL) are presented for p(T) = 1 to 4 GeV/c and probe the higher range of Bjorken x of the gluon (x(g)) with better statistical precision than our previous measurements at root s = 200 GeV.
These measurements are sensitive to the gluon polarization in the proton for 0.06 { x(g) { 0.4.