Effects of transversity in deep-inelastic scattering by polarized protons

Physikalisches Institut, Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
Physics Letters B (Impact Factor: 6.02). 09/2010; 693(1):11-16. DOI: 10.1016/j.physletb.2010.08.012

ABSTRACT Single-spin asymmetries for pions and charged kaons are measured in semi-inclusive deep-inelastic scattering of positrons and electrons off a transversely nuclear-polarized hydrogen target. The dependence of the cross section on the azimuthal angles of the target polarization (ϕS) and the produced hadron (ϕ) is found to have a substantial sin(ϕ+ϕS) modulation for the production of π+, π− and K+. This Fourier component can be interpreted in terms of non-zero transversity distribution functions and non-zero favored and disfavored Collins fragmentation functions with opposite sign. For π0 and K− production the amplitude of this Fourier component is consistent with zero.

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Available from: Vahagn Gharibyan, Jun 19, 2015
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