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Spin-independent and double-spin cos(phi) asymmetries in semi-inclusive pion electroproduction

K. A. Oganessyan·L. S. Asilyan·M. Anselmino·E. De Sanctis
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Abstract

We consider the cos(phi) dependence of the longitudinal double-spin asymmetry for charged pion electroproduction in semi-inclusive deep inelastic scattering, emphasizing intrinsic transverse momentum effects. This azimuthal asymmetry allows to measure the cos(phi) moments of the unpolarized and double-spin cross-section, simultaneously. The size of the asymmetry, in the approximation where all twist-3 interaction-dependent distribution and fragmentation functions are set to zero, is estimated for HERMES kinematics; both the spin-independent and the double-spin cos(phi) moments are predicted to be sizeable and negative.

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K. A. Oganessyan, L. S. Asilyan, M. Anselmino, E. De Sanctis. 2003-03-21. Spin-independent and double-spin cos(phi) asymmetries in semi-inclusive pion electroproduction. https://doi.org/10.1016/s0370-2693(03)00652-x

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