Article

Measurement of single-spin azimuthal asymmetries in semi-inclusive electroproduction of pions and kaons on a longitudinally polarised deuterium target

Physikalisches Institut, Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
Physics Letters B (Impact Factor: 6.02). 06/2003; 562(2003)(3-4):182-192. DOI: 10.1016/S0370-2693(03)00566-5

ABSTRACT Single-spin asymmetries have been measured for semi-inclusive electroproduction of π+, π−, π0 and K+ mesons in deep-inelastic scattering off a longitudinally polarised deuterium target. The asymmetries appear in the distribution of the hadrons in the azimuthal angle φ around the virtual photon direction, relative to the lepton scattering plane. The corresponding analysing powers in the sinφ moment of the cross section are 0.012±0.002(stat.)±0.002(syst.) for π+, 0.006±0.003(stat.)±0.002(syst.) for π−, 0.021±0.005(stat.)±0.003(syst.) for π0 and 0.013±0.006(stat.)±0.003(syst.) for K+. The sin2φ moments are compatible with zero for all particles.

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