2004/02/04 by SMC Collaboration, B. Adeva
Physics and Astronomy · #hep-ex
published as Phys.Rev. D70 (2004) 012002 · 13 pages, 6 figures, 4 tables, submitted to Phys. Rev. D
arxiv created 2004/02/04 · arxiv updated 2009/12/01
We present a measurement of the longitudinal spin cross section asymmetry for deep inelastic muon-nucleon interactions with two high transverse momentum hadrons in the final state. Two methods of event classification are used to increase the contribution of the Photon Gluon Fusion process to above 30%. The most effective one, based on a neural network approach, provides the asymmetries Ap(lN->lhhX)=0.030+/-0.057+/-0.010 and Ad(lN->lhhX)=0.070+/-0.076+/-0.010. From these values we derive an averaged gluon polarization delta(G)/G=-0.20+/-0.28+/-0.10 at an average fraction of nucleon momentum carried by gluons eta=0.07.