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Single-spin asymmetry in DVCS: fragmentation region of polarised lepton

I. Akushevich·E. Kuraev·B. Shaikhatdenov
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Abstract

For the kinematical region when a hard photon is emitted predominantly close to the direction of motion of a longitudinally polarized initial electron and relatively small momentum transfer to a proton we calculate the azimuthal asymmetry of photon emission. It arises from the interference of the Bethe-Heitler amplitude and those which are described by a heavy photon impact factor. Azimuthal asymmetry does not decrease in the limit of infinite cms energy. Lowest order expression for the impact factor of a heavy photon is presented.

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I. Akushevich, E. Kuraev, B. Shaikhatdenov. 2001-03-09. Single-spin asymmetry in DVCS: fragmentation region of polarised lepton. https://doi.org/10.1103/physrevd.64.094010

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