Transverse target spin asymmetries in exclusive ρ0 muoproduction
C. Adolph (Universität Erlangen–Nürnberg, Physikalisches Institut, Erlangen, 91054, Germany); R. Akhunzyanov (Joint Institute for Nuclear Research, Moscow Region, Dubna, 141980, Russia); M.G. Alekseev (Trieste Section of INFN, Trieste, 34127, Italy); V.Yu. Alexakhin (Joint Institute for Nuclear Research, Moscow Region, Dubna, 141980, Russia); Yu. Alexandrov (Lebedev Physical Institute, Moscow, 119991, Russia); et al - Show all 226 authors
Exclusive production of Ï0 mesons was studied at the COMPASS experiment by scattering 160 GeV/c muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured as a function of Q2 , xBj , or pT2 . The sinÏS asymmetry is found to be â0.019±0.008(stat.)±0.003(syst.) . All other asymmetries are also found to be of small magnitude and consistent with zero within experimental uncertainties. Very recent calculations using a GPD-based model agree well with the present results. The data is interpreted as evidence for the existence of chiral-odd, transverse generalized parton distributions.
