Scaling tests of the cross section for deeply virtual Compton scattering.
We present the first measurements of the e[over -->]p-->epgamma cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region. The Q(2) dependence (from 1.5 to 2.3 GeV(2)) of the helicity-dependent cross section indicates the twist-2 dominance of DVCS, proving that generalized parton distributions (GPDs) are accessible to experiment at moderate Q(2). The helicity-independent cross section is also measured at Q(2)=2.3 GeV(2). We present the first model-independent measurement of linear combinations of GPDs and GPD integrals up to the twist-3 approximation.
Camacho
C Muñoz
CM
CEA Saclay, DAPNIA/SPhN, F-91191 Gif-sur-Yvette, France.
Camsonne
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Mazouz
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Ferdi
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Gavalian
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Kuchina
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Amarian
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Aniol
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Beaumel
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Benaoum
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Bertin
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Brossard
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Chen
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Chudakov
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Craver
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Cusanno
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de Jager
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Deur
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Feuerbach
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Fieschi
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Frullani
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Garçon
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Garibaldi
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Gayou
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Gilman
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Gomez
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Gueye
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Guichon
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Guillon
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Hansen
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Hayes
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Higinbotham
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Holmstrom
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Hyde-Wright
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Ibrahim
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Igarashi
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Jiang
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Jo
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Kaufman
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Kelleher
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Kolarkar
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Kumbartzki
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Laveissière
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Lerose
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Lindgren
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Liyanage
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Margaziotis
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Meziani
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McCormick
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Michaels
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Michel
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Moffit
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Monaghan
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Nanda
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Nelyubin
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Potokar
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Qiang
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Ransome
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Réal
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Reitz
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Roblin
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Roche
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Sabatié
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Saha
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Sirca
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Slifer
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Solvignon
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Subedi
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Sulkosky
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Ulmer
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Voutier
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Wang
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Weinstein
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Wojtsekhowski
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Zheng
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Zhu
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