Transverse target spin asymmetries in exclusive ρ0 muoproduction
Universität Freiburg, Physikalisches Institut, 79104 Freiburg, Germany
Published online: 9 June 2014
COMPASS has studied exclusive production of ρ0 mesons using a 160 GeV/c muon beam and a transversely polarised NH3 target. Five single-spin and three double-spin azimuthal aymmetries were measured in dependence on Q2, xBj, or pT2. Except the sin ϕS asymmetry, obtained to be − 0.019 ± 0.008(stat.) ± 0.003(syst.), all others were found to be consistent with zero within experimental uncertainties. Phenomenological GPD-based model calculations agree well with the data and interpret the result as evidence for the existence of chiral-odd, transverse generalised parton distributions.
© Owned by the authors, published by EDP Sciences, 2014
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