PION-DEUTERON DISPERSION RELATIONS IN IMPULSE APPROXIMATION
Dispersion relations for pion-deuteron forward scattering pi + D yields pi + D are discussed by using the impulse approximation for the calculation of the contribution in the unphysical region that is due to the absorptive process pi + D yields N + N. Special regard is taken to the anomalous situation that is investigated by explicit analytic continuation of the contribution from the absorptive process in the dispersion relations with respect to the pion mass. It is found that an anomalous logarithmic branch point and an anomalous pole appear at the same point, which coincides with that found in perturbation theory where the deuteron is treated as elementary. It turns out that the anonnalous situation is only governed by the asymptotic behavior of the occurring deuteron wave functions. It is further shown that the spin-flip dispersion relation can be used for a determination of the pion-nucleon coupling constant. The value found by employing the impulse approximation for the spinflip amplitude in the observable region of the dispersion relation agrees within 10% with that following from the corresponding pion-nucleon dispersion relation. For this agreement the consideration of the anomalous pole contribution is necessary. (auth)
- Research Organization:
- Humboldt-Universitat, Berlin and Deutschen Akademie der Wissenschaften, Berlin
- NSA Number:
- NSA-18-006008
- OSTI ID:
- 4118623
- Journal Information:
- Nuclear Physics (Netherlands) Divided into Nucl. Phys. A and Nucl. Phys. B, Journal Name: Nuclear Physics (Netherlands) Divided into Nucl. Phys. A and Nucl. Phys. B Vol. Vol: 48; ISSN NUPHA
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
Dispersion relations for pion-deuteron scattering. II
Analyticity Properties of the Meson-Deuteron Elastic-Scattering Amplitudes at Low Energy