Compton scattering on protons has been measured at a mean photon energy of 6 GeV and four-momentum transfers − t between 0.06 and 0.60 (GeV/ c ) 2 . The differential cross section shows a diffraction-like behaviour. The cross section extrapolated to t =0 is in fair agreement with the optical point. Discrepancies with the vector meson dominance model are pointed out.
No description provided.
Elastic scattering of linearly polarized photons on protons has been measured between 3.2 and 3.7 GeV for four-momentum transfers ranging from −0.1 to −0.7 (GeV/ c ) 2 . The observed cross section asymmetry in this range is consistent with zero within ±0.05.
No description provided.
Proton Compton scattering has been measured in a coincidence experiment at photon energies between 2.2 and 7 GeV and four-momentum transfers t between −0.06 and −0.85(GeV/ c ) 2 . For ∣ t ∣ ⩽ 0.4 (GeV/ c ) 2 fits of the form d σ /d t = ( A · exp( Bt )) yield forward cross sections A in good agreement with the values calculated from the total hadronic γ p cross section via the optical theorem and the forward dispersion relation. The slopes B do not show a significant energy dependence, the mean value being 5.7 ± 0.4 (GeV/ c ) −2 . The cross section is substantially larger than predicted by the vector-meson dominance model.
No description provided.
No description provided.
No description provided.
The real part of the forward amplitude for Compton scattering on protons was measured through the interference between the Compton and Bethe-Heithler amplitudes by detecting the zero-degree electron pairs asymmetrically. The measurement was made at an average photon energy of 〈k〉=2.2 GeV, and an average momentum transfer to the recoil proton 〈t〉=−0.027 (GeV/c)2. The result confirms the prediction of the Kramers-Kronig relation.
No description provided.
The differential cross sections for γp→γp and γp→π0p have been measured for incident photon energies in the range of 2 to 6 GeV and for |t| ranging from 0.7 to 4.3 GeV2. This corresponds to a center-of-mass angle range of 45° to 128°. The energy dependence of the data is compared to that predicted by several parton models.
No description provided.
No description provided.
No description provided.
Forum