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Flavor decomposition of the sea quark helicity distributions in the nucleon from semi-inclusive deep-inelastic scattering

HERMES collaboration·A. Airapetian
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Abstract

Double-spin asymmetries of semi-inclusive cross sections for the production of identified pions and kaons have been measured in deep-inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions including those for three sea quark flavors were extracted from these data together with re-analyzed previous data for identified pions from a hydrogen target. These distributions are consistent with zero for all three sea flavors. A recently predicted flavor asymmetry in the polarization of the light quark sea appears to be disfavored by the data.

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HERMES collaboration, A. Airapetian. 2003-11-07. Flavor decomposition of the sea quark helicity distributions in the nucleon from semi-inclusive deep-inelastic scattering. https://doi.org/10.1103/physrevlett.92.012005

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