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arXiv · 0906.3918

Observation of the Naive-T-odd Sivers Effect in Deep-Inelastic Scattering

The HERMES Collaboration
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Abstract

Azimuthal single-spin asymmetries of lepto-produced pions and charged kaons were measured on a transversely polarized hydrogen target. Evidence for a naive-T-odd, transverse-momentum-dependent parton distribution function is deduced from non-vanishing Sivers effects for pi+, pi0, and K+, K-, as well as in the difference of the pi+ and pi- cross sections.

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The HERMES Collaboration. 2009-06-22. Observation of the Naive-T-odd Sivers Effect in Deep-Inelastic Scattering. https://doi.org/10.1103/physrevlett.103.152002

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