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arXiv · hep-ph/0002091

Single-spin Azimuthal Asymmetries in the ``Reduced Twist-3 Approximation''

E. De Sanctis·W. -D. Nowak·K. A. Oganessyan
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Abstract

We consider the single-spin azimuthal asymmetries recently measured at the HERMES experiment for charged pions produced in semi-inclusive deep inelastic scattering of leptons off longitudinally polarized protons. Guided by the experimental results and assuming a vanishing twist-2 transverse quark spin distribution in the longitudinally polarized nucleon, denoted as ``reduced twist-3 approximation'', a self-consistent description of the observed single-spin asymmetries is obtained. In addition, predictions are given for the z dependence of the single target-spin asymmetry.

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E. De Sanctis, W. -D. Nowak, K. A. Oganessyan. 2000-03-03. Single-spin Azimuthal Asymmetries in the ``Reduced Twist-3 Approximation''. https://doi.org/10.1016/s0370-2693(00)00596-7

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