Roy-Steiner equations for pi N scattering
Abstract
Starting from hyperbolic dispersion relations for the invariant amplitudes of pion-nucleon scattering together with crossing symmetry and unitarity, one can derive a closed system of integral equations for the partial waves of both the s-channel (pi N --> pi N) and the t-channel (pi pi --> Nbar N) reaction, called Roy-Steiner equations. After giving a brief overview of the Roy-Steiner system for pi N scattering, we demonstrate that the solution of the t-channel subsystem, which represents the first step in solving the full system, can be achieved by means of Muskhelishvili-Omn\`es techniques. In particular, we present results for the P-waves featuring in the dispersive analysis of the electromagnetic form factors of the nucleon.
Cite
@article{arxiv.1211.7285,
title = {Roy-Steiner equations for pi N scattering},
author = {Christoph Ditsche and Martin Hoferichter and Bastian Kubis and Ulf-G. Meißner},
journal= {arXiv preprint arXiv:1211.7285},
year = {2013}
}
Comments
6 pages, 3 figures, proceedings for The 7th International Workshop on Chiral Dynamics, Jefferson Lab, Newport News, Virginia, USA, August 6-10, 2012