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arXiv · hep-ex/0107043

Observation of exclusive DVCS in polarized electron beam asymmetry measurements

CLAS Collaboration·S. Stepanyan
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Abstract

We report the first results of the beam spin asymmetry measured in the reaction e + p -> e + p + gamma at a beam energy of 4.25 GeV. A large asymmetry with a sin(phi) modulation is observed, as predicted for the interference term of Deeply Virtual Compton Scattering and the Bethe-Heitler process. The amplitude of this modulation is alpha = 0.202 +/- 0.028. In leading-order and leading-twist pQCD, the alpha is directly proportional to the imaginary part of the DVCS amplitude.

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CLAS Collaboration, S. Stepanyan. 2001-09-18. Observation of exclusive DVCS in polarized electron beam asymmetry measurements. https://doi.org/10.1103/physrevlett.87.182002

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