SOME CORRECTIONS TO PARTIAL WAVE DISPERSION RELATIONS FOR PION PHOTOPRODUCTION
The exact one-dimensional dispersion relations for partial wave amplitudes of pion-nucleon scattering and of pion photoproduction on nucleons were derived and compared. It was found that a non-constant comparison function must be introduced into the relationship between the scattering partial wave amplitude which is dominant at low energies and the corresponding photoproduction partial wave amplitude, in order that each amplitude obey its own exact dispersion relation at the same time that the two amplitudes are related by the unitarity condition. The results of experimental determinations of pion-nucleon scattering phase shifts were compiled, and the coefficients of interpolation formulae for the phase shifts were evaluated. The experimental results of photoproduction of neutral and of positive pions on protons at energies up to 500 Mev were compared to calculated cross sections for various combinations of choice of phase shifts and inclusion of the comparison function. The photoproduction cross sections were also calculated with the inclusion of the contribution of the bipion.'' The effect of this contribution was generally greater than the effect of either the comparison function or a change of phase shifts. On the basis of the e (as Fe/sup 59 /sup +/ angular distribution it appeared that the coupling parameter for this contribution should be negative. (Dissertation Abstr. XXIII, No. 8)
- Research Organization:
- Originating Research Org. not identified
- NSA Number:
- NSA-17-020948
- OSTI ID:
- 4694868
- Resource Relation:
- Other Information: Thesis. Orig. Receipt Date: 31-DEC-63
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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