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arXiv · 0803.2367

Evidence for a Transverse Single-Spin Asymmetry in Leptoproduction of pi+pi- Pairs

HERMES Collaboration·A. Airapetian
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Abstract

A single-spin asymmetry was measured in the azimuthal distribution of pi+pi- pairs produced in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target. For the first time, evidence is found for a correlation between the transverse target polarization and the azimuthal orientation of the plane containing the two pions.The corresponding single-spin asymmetry is expected to be related to the product of the little-known quark transversity distribution function and an unknown naive-T-odd chiral-odd dihadron fragmentation function.

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HERMES Collaboration, A. Airapetian. 2008-05-23. Evidence for a Transverse Single-Spin Asymmetry in Leptoproduction of pi+pi- Pairs. https://doi.org/10.1088/1126-6708%2F2008%2F06%2F017

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