Abstract
We present an improved measurement of the double helicity asymmetry for production in polarized proton-proton scattering at employing the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The improvements to our previous measurement come from two main factors: Inclusion of a new data set from the 2004 RHIC run with higher beam polarizations than the earlier run and a recalibration of the beam polarization measurements for the earlier run, which resulted in reduced uncertainties and increased beam polarizations. The results are compared to a Next to Leading Order (NLO) perturbative Quantum Chromodynamics (pQCD) calculation with a range of polarized gluon distributions.
- Received 1 February 2006
DOI:https://doi.org/10.1103/PhysRevD.73.091102
©2006 American Physical Society