Spin asymmetries for events with high p(T) hadrons in DIS and an evaluation of the gluon polarization

Adeva B., Arik E., Arvidson A., Badelek B., Baum G., Berglund P., ...More

PHYSICAL REVIEW D, vol.70, no.1, 2004 (Journal Indexed in SCI) identifier

  • Publication Type: Article / Article
  • Volume: 70 Issue: 1
  • Publication Date: 2004
  • Doi Number: 10.1103/physrevd.70.012002
  • Title of Journal : PHYSICAL REVIEW D


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 A(p)lN(-->)lhhX=0.030+/-0.057(stat)+/-0.010(syst) and A(d)lN(-->)lhhX=0.070+/-0.076(stat)+/-0.010(syst). From these values we derive an averaged gluon polarization DeltaG/G=-0.20+/-0.28(stat)+/-0.10(syst) at an average fraction of nucleon momentum carried by gluons =0.07.