Measurement of angular distributions of Drell-Yan dimuons in p+d interactions at 800 GeV/c.
/ Authors
L. Zhu, L. Zhu, J. Peng, P. Reimer, P. Reimer, T. Awes, M. Brooks, C. Brown, J. D. Bush, T. Carey
and 35 more authors
T. Chang, W. Cooper, C. Gagliardi, G. Garvey, D. Geesaman, E. Hawker, X. He, L. Isenhower, D. Kaplan, S. Kaufman, S. Klinksiek, D. Koetke, D. Lee, W. Lee, W. Lee, M. Leitch, N. Makins, P. McGaughey, J. Moss, B. Mueller, P. Nord, V. Papavassiliou, B. Park, G. Petitt, M. Sadler, W. Sondheim, P. Stankus, T. Thompson, R. Towell, R. Tribble, M. Vasiliev, J. Webb, J. Willis, D. Wise, G. Young
/ Abstract
We report a measurement of the angular distributions of Drell-Yan dimuons produced using an 800 GeV/c proton beam on a deuterium target. The muon angular distributions in the dilepton rest frame have been measured over the kinematic range 4.5<m{mu mu}<15 GeV/c{2}, 0<p{T}<4 GeV/c, and 0<x{F}<0.8. No significant cos2phi dependence is found in these proton-induced Drell-Yan data, in contrast with the situation for pion-induced Drell-Yan data. The data are compared with expectations from models which attribute the cos2phi distribution to a QCD vacuum effect or to the presence of the transverse-momentum-dependent Boer-Mulders structure function h{1}{perpendicular}. Constraints on the magnitude of the sea-quark h{1}{perpendicular} structure functions are obtained.
Journal: Physical review letters