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arXiv · 0707.2486

Transverse Target-Spin Asymmetry of Exclusive $ρ^0$ Meson Production on Proton at HERMES

Armine Rostomyan·Jeroen Dreschler
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Abstract

Preliminary measurements are reported on the azimuthal single-spin asymmetry of exclusive rho0 mesons for a transversely polarized hydrogen target at HERMES using the 27.6 GeV HERA positron beam. Within the generalized parton distribution (GPD) formalism, this asymmetry is sensitive to the total angular momentum of quarks and gluons in the nucleon. Since the GPD formalism is only valid for mesons produced by longitudinal photons, the transverse target-spin asymmetry of longitudinal rho0 mesons is extracted assuming s-channel helicity conservation and compared to theoretical calculations.

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Armine Rostomyan, Jeroen Dreschler. 2007-07-17. Transverse Target-Spin Asymmetry of Exclusive $ρ^0$ Meson Production on Proton at HERMES. https://arxiv.org/abs/0707.2486

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