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Subleading-twist effects in single-spin asymmetries in semi-inclusive deep-inelastic scattering on a longitudinally polarized hydrogen target

The HERMES Collaboration·A. Airapetian·:
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Abstract

Single-spin asymmetries in the semi-inclusive production of charged pions in deep-inelastic scattering from transversely and longitudinally polarized proton targets are combined to evaluate the subleading-twist contribution to the longitudinal case. This contribution is significantly positive for (π^+) mesons and dominates the asymmetries on a longitudinally polarized target previously measured by \hermes. The subleading-twist contribution for (π^-) mesons is found to be small.

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The HERMES Collaboration, A. Airapetian, :. 2005-06-19. Subleading-twist effects in single-spin asymmetries in semi-inclusive deep-inelastic scattering on a longitudinally polarized hydrogen target. https://doi.org/10.1016/j.physletb.2005.06.067

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