1 research outputs found
Epidemiological applications of long-term stress in daily life.
The gluon polarisation in the nucleon has been determined by detecting charm production via D0 meson decay to charged K and \u3c0 in polarised muon scattering off a longitudinally polarised deuteron target. The data were taken by the COMPASS Collaboration at CERN between 2002 and 2006 and correspond to an integrated luminosity of 2.8 fb 121. The dominant underlying process of charm production is the photon\u2013gluon fusion to a_(c barc) pair. A leading order QCD approach gives an average gluon polarisation of _x= 120.49\ub10.27(stat)\ub10.11(syst) at a scale \u3bc^2 4813 (GeV/c)^2 and at an average gluon momentum fraction 480.11. The longitudinal cross-section asymmetry for D0 production is presented in bins of the transverse momentum and the energy of the D0 meson