Differential cross sections for the reactions γp→π0p, π+n and γn→π−p, π0n were measured in a single experiment using tagged photons in the energy region 240-450 MeV incident on H21 and H22 targets. Results of the measurements of the ratios π0nπ0p and π−pπ+n are presented. The ratio of isotensor to isovector amplitude is found to be 0.00±0.02.
No description provided.
No description provided.
No description provided.
The differential cross-section for π+ photoproduction from hydrogen by γ-rays of laboratory energy 187 MeV has been measured at four angles. Two identical counter systems, designed to detect low energy pions unambiguosly in intense electron and γ-ray backgrounds, were used in conjunction with a cylindrical liquid hydrogen target, of very low boil-off rate. The cross-sections at laboratory angles of 39.2°, 66.7°, 111.6°, and 134° are 7.49±0.47, 8.10±0.57, 8.36±0.61 and 9.54±0.61, ·10−30cm2/sr, respectively, where the assigned errors refer only to the relative values. The absolute cross-sections are in substantial agreement with the dispersion theory and confirm the front to back asymmetry.
No description provided.