Measurement of deeply virtual compton scattering with a polarized-proton target.
The longitudinal target-spin asymmetry AUL for the exclusive electroproduction of high-energy photons was measured for the first time in ep-->e;'pgamma. The data have been accumulated at JLab with the CLAS spectrometer using 5.7 GeV electrons and a longitudinally polarized NH3 target. A significant azimuthal angular dependence was observed, resulting from the interference of the deeply virtual Compton scattering and Bethe-Heitler processes. The amplitude of the sinvarphi moment is 0.252+/-0.042stat+/-0.020sys. Theoretical calculations are in good agreement with the magnitude and the kinematic dependence of the target-spin asymmetry, which is sensitive to the generalized parton distributions H and H.
Chen
S
S
Florida State University, Tallahassee, Florida 32306, USA.
Avakian
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Burkert
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Eugenio
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Adams
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Amarian
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Ambrozewicz
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Berman
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Biselli
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Bonner
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Bouchigny
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Boiarinov
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Bosted
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Bradford
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Branford
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Briscoe
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Brooks
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Bültmann
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Butuceanu
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Calarco
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Careccia
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Carman
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Carnahan
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Cazes
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Cole
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Collins
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Coltharp
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Corvisiero
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Crabb
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Crannell
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Crede
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Cummings
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DeMasi
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DeVita
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De Sanctis
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Degtyarenko
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Denizli
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Dennis
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Deur
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Dhuga
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Djalali
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Donnelly
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Dzyubak
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Fatemi
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Fedotov
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Feldman
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Guidal
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Guillo
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Guler
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Guo
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Gyurjyan
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Hadjidakis
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Hafidi
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Hakobyan
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Heddle
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Hersman
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Holtrop
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Huertas
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Ireland
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Ishkhanov
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Isupov
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Ito
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Khandaker
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Kim
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Kim
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Klusman
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Laget
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Langheinrich
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Lawrence
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Lima
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Livingston
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Lu
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Lukashin
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MacCormick
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Markov
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Mecking
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Meyer
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Mibe
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Mikhailov
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Minehart
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Mirazita
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Miskimen
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Mokeev
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Morand
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Morrow
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Mueller
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Mutchler
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Napolitano
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Nasseripour
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Natasha
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Niccolai
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Niculescu
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Niczyporuk
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Niyazov
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Osipenko
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Park
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Pasyuk
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Paterson
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Pogorelko
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Raue
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Rosner
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Yun
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Zhao
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