Measurement of deeply virtual compton scattering beam-spin asymmetries

CLAS Collaboration, F. X. Girod, R. A. Niyazov, H. Avakian, J. Ball, I. Bedlinskiy, V. D. Burkert, R. De Masi, L. Elouadrhiri, M. Garcon, M. Guidal, H. S. Jo, K. Joo, V. Kubarovsky, S. V. Kuleshov, M. MacCormick, S. Niccolai, O. Pogorelko, F. Sabatie, S. StepanyanP. Stoler, M. Ungaro, B. Zhao, M. J. Amaryan, P. Ambrozewicz, M. Anghinolfi, G. Asryan, H. Bagdasaryan, N. Baillie, J. P. Ball, N. A. Baltzell, V. Batourine, M. Battaglieri, M. Bellis, N. Benmouna, B. L. Berman, A. S. Biselli, L. Blaszczyk, S. Bouchigny, S. Boiarinov, R. Bradford, D. Branford, W. J. Briscoe, W. K. Brooks, S. Bultmann, C. Butuceanu, J. R. Calarco, S. L. Careccia, D. S. Carman, L. Casey, D. P. Watts

Research output: Contribution to journalArticlepeer-review

Abstract

The beam-spin asymmetries in the hard exclusive electroproduction of photons on the proton (e(->)p -> ep gamma) were measured over a wide kinematic range and with high statistical accuracy. These asymmetries result from the interference of the Bethe-Heitler process and of deeply virtual Compton scattering. Over the whole kinematic range (x(B) from 0.11 to 0.58, Q(2) from 1 to 4.8 GeV2, -t from 0.09 to 1.8 GeV2), the azimuthal dependence of the asymmetries is compatible with expectations from leading-twist dominance, A similar or equal to a sin phi/(1+c cos phi). This extensive set of data can thus be used to constrain significantly the generalized parton distributions of the nucleon in the valence quark sector.

Original languageEnglish
Article number162002
Number of pages6
JournalPhysical Review Letters
Volume100
Issue number16
DOIs
Publication statusPublished - 25 Apr 2008

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