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arXiv · hep-ex/0301005

Measurement of Beam-Spin Asymmetries for Deep Inelastic $π^+$ Electroproduction

CLAS Collaboration·H. Avakian
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Abstract

We report the first evidence for a non-zero beam-spin azimuthal asymmetry in the electroproduction of positive pions in the deep-inelastic region. Data have been obtained using a polarized electron beam of 4.3 GeV with the CLAS detector at the Thomas Jefferson National Accelerator Facility (JLab). The amplitude of the $\sinϕ$ modulation increases with the momentum of the pion relative to the virtual photon, $z$, with an average amplitude of $0.038 \pm 0.005 \pm 0.003$ for $0.5 < z < 0.8$ range.

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CLAS Collaboration, H. Avakian. 2004-04-27. Measurement of Beam-Spin Asymmetries for Deep Inelastic $π^+$ Electroproduction. https://doi.org/10.1103/physrevd.69.112004

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