An N/D study of the S 11 channel πN scattering amplitude *
- 1 February 2022
- journal article
- research article
- Published by IOP Publishing in Chinese Physics C
- Vol. 46 (2), 023104
- https://doi.org/10.1088/1674-1137/ac31a4
Abstract
Extensive dynamical N/D calculations are conducted in the study of S-11 channel low energy pi N scatterings, based on various phenomenological model inputs of left cuts at the tree level. The subtleties of the singular behavior of the partial wave amplitude, at the origin of the complex s plane, are analysed in detail. Furthermore, it is found that the dispersion representation for the phase shift, delta, must be modified in the case of pi N scatterings. An additional contribution from the dispersion integral exists, which approximately cancels the contribution of the two virtual poles located near the end points of the segment cut, induced by u channel nucleon exchanges. With limited reliance on the details of the dynamical inputs, the subthreshold resonance N* (890) survives.Keywords
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