2015/09/04 by Maxime Levillain, Levillain, Maxime
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #hep-ex #hep-ph
paper · pdf · doi:10.48550/arxiv.1509.01419
Talk presented CIPANP2015. 6 pages, LaTeX, 7 pdf figures and 1 png figure
arxiv created 2015/09/04 · arxiv updated 2015/09/07
In order to understand the gluon contribution to the nucleon spin, some experiments can study the production of hadrons at high transverse momemtum from lepton-nucleon or nucleon-nucleon scattering. RHIC has recently measured such double spin asymmetries ALL(pT) for pion production at high center of mass energies, and inclusion of its data to global fits based on NLO collinear pQCD calculations gives some constraints on the gluon polarization in the range 0.05<xg<0.2. To complement these results at COMPASS range, we will present preliminary COMPASS results on double longitudinal spin asymmetries ALL(pT) for single hadron production measured on deuteron and proton target at Q2<1 GeV2, pT>1 GeV/c and center of mass energy √(s)≈ 18 GeV. All COMPASS data taken from 2002 to 2011 by scattering 160 GeV polarized muons on longitudinally polarized 6LiD and NH3 targets have been used, and the number of hadrons collected with pT>1 GeV/c for this analysis amounts to about 10 millions. The obtained asymmetries will be compared to theoretical predictions of at NLO without gluon resummation calculation.