Compton-scattering cross section on the proton at high momentum transfer.
نویسندگان
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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ورودعنوان ژورنال:
- Physical review letters
دوره 98 15 شماره
صفحات -
تاریخ انتشار 2007