Summary
An experimental analysis of the process
is presented. Theσ(−)/σ(+) ratio has been measured in the photon energy interval (170÷230) MeV and Lab. angles 45°, 75°, 105°, 150°. The results are interpreted on the base of the impulse approximation with the aim of getting information on the processhv+n →π −+p.
Riassunto
Viene presentata un’analisi sperimentale del processo
Il rapportoσ(−)/σ(+) è stato misurato nell’intervallo di energia dei fotoni compreso tra 170 e 230 MeV. I risultati sono stati esaminati usando l’«impulse approximation» con lo scopo di ottenere informazioni sul processohv+n → π−+p.
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The effective numerical evaluations of the cross-sections, starting from the quite complicated amplitudes given byChew et al., have been worked out by one of us (M. Beneventano) and then checked on many points by the other authors of this paper. Some checks have also been done comparing these calculations with some of those accomplished byE. Goldwasser. In spite of the fact that we do not exclude the occurrence of some mistake and some wrong sign in this very long and tedious work, we believe that the calculated curves represent the predictions of the dispersion relations without substantial errors.
The authors are very indebted to Dr.C. Robinson, Physics Department, University of Illinois, who notified them of some possible misunderstanding in the meaning of the «standard conditions» of the monitor used by them during the performance of the experiment.
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Beneventano, M., Bernardini, G., Stoppini, G. et al. Photoproduction of charged pions in deuterium. Nuovo Cim 10, 1109–1142 (1958). https://doi.org/10.1007/BF02859573
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DOI: https://doi.org/10.1007/BF02859573