Scaling tests of the cross section for deeply virtual Compton scattering.

نویسندگان

  • C Muñoz Camacho
  • A Camsonne
  • M Mazouz
  • C Ferdi
  • G Gavalian
  • E Kuchina
  • M Amarian
  • K A Aniol
  • M Beaumel
  • H Benaoum
  • P Bertin
  • M Brossard
  • J-P Chen
  • E Chudakov
  • B Craver
  • F Cusanno
  • C W de Jager
  • A Deur
  • R Feuerbach
  • J-M Fieschi
  • S Frullani
  • M Garçon
  • F Garibaldi
  • O Gayou
  • R Gilman
  • J Gomez
  • P Gueye
  • P A M Guichon
  • B Guillon
  • O Hansen
  • D Hayes
  • D Higinbotham
  • T Holmstrom
  • C E Hyde-Wright
  • H Ibrahim
  • R Igarashi
  • X Jiang
  • H S Jo
  • L J Kaufman
  • A Kelleher
  • A Kolarkar
  • G Kumbartzki
  • G Laveissière
  • J J Lerose
  • R Lindgren
  • N Liyanage
  • H-J Lu
  • D J Margaziotis
  • Z-E Meziani
  • K McCormick
  • R Michaels
  • B Michel
  • B Moffit
  • P Monaghan
  • S Nanda
  • V Nelyubin
  • M Potokar
  • Y Qiang
  • R D Ransome
  • J-S Réal
  • B Reitz
  • Y Roblin
  • J Roche
  • F Sabatié
  • A Saha
  • S Sirca
  • K Slifer
  • P Solvignon
  • R Subedi
  • V Sulkosky
  • P E Ulmer
  • E Voutier
  • K Wang
  • L B Weinstein
  • B Wojtsekhowski
  • X Zheng
  • L Zhu
چکیده

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.

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عنوان ژورنال:
  • Physical review letters

دوره 97 26  شماره 

صفحات  -

تاریخ انتشار 2006