Compton-scattering cross section on the proton at high momentum transfer.

نویسندگان

  • A Danagoulian
  • V H Mamyan
  • M Roedelbronn
  • K A Aniol
  • J R M Annand
  • P Y Bertin
  • L Bimbot
  • P Bosted
  • J R Calarco
  • A Camsonne
  • C C Chang
  • T-H Chang
  • J-P Chen
  • Seonho Choi
  • E Chudakov
  • P Degtyarenko
  • C W de Jager
  • A Deur
  • D Dutta
  • K Egiyan
  • H Gao
  • F Garibaldi
  • O Gayou
  • R Gilman
  • A Glamazdin
  • C Glashausser
  • J Gomez
  • D J Hamilton
  • J-O Hansen
  • D Hayes
  • D W Higinbotham
  • W Hinton
  • T Horn
  • C Howell
  • T Hunyady
  • C E Hyde
  • X Jiang
  • M K Jones
  • M Khandaker
  • A Ketikyan
  • V Kubarovsky
  • K Kramer
  • G Kumbartzki
  • G Laveissière
  • J Lerose
  • R A Lindgren
  • D J Margaziotis
  • P Markowitz
  • K McCormick
  • D G Meekins
  • Z-E Meziani
  • R Michaels
  • P Moussiegt
  • S Nanda
  • A M Nathan
  • D M Nikolenko
  • V Nelyubin
  • B E Norum
  • K Paschke
  • L Pentchev
  • C F Perdrisat
  • E Piasetzky
  • R Pomatsalyuk
  • V A Punjabi
  • I Rachek
  • A Radyushkin
  • B Reitz
  • R Roche
  • G Ron
  • F Sabatié
  • A Saha
  • N Savvinov
  • A Shahinyan
  • Y Shestakov
  • S Sirca
  • K Slifer
  • P Solvignon
  • P Stoler
  • S Tajima
  • V Sulkosky
  • L Todor
  • B Vlahovic
  • L B Weinstein
  • K Wang
  • B Wojtsekhowski
  • H Voskanyan
  • H Xiang
  • X Zheng
  • L Zhu
چکیده

Cross-section values for Compton scattering on the proton were measured at 25 kinematic settings over the range s=5-11 and -t=2-7 GeV2 with a statistical accuracy of a few percent. The scaling power for the s dependence of the cross section at fixed center-of-mass angle was found to be 8.0+/-0.2, strongly inconsistent with the prediction of perturbative QCD. The observed cross-section values are in fair agreement with the calculations using the handbag mechanism, in which the external photons couple to a single quark.

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عنوان ژورنال:
  • Physical review letters

دوره 98 15  شماره 

صفحات  -

تاریخ انتشار 2007