The in-medium isovector pi N amplitude from low energy pion scattering
Nuclear Experiment
2009-11-10 v2
Abstract
Differential cross sections for elastic scattering of 21.5 MeV positive and negative pions by Si, Ca, Ni and Zr have been measured as part of a study of the pion-nucleus potential across threshold. The `anomalous' repulsion in the s-wave term was observed, as is the case with pionic atoms. The extra repulsion can be accounted for by a chiral-motivated model where the pion decay constant is modified in the medium. Unlike in pionic atoms, the anomaly cannot be removed by merely introducing an empirical on-shell energy dependence.
Keywords
Cite
@article{arxiv.nucl-ex/0404031,
title = {The in-medium isovector pi N amplitude from low energy pion scattering},
author = {E. Friedman and M. Bauer and J. Breitschopf and H. Clement and H. Denz and E. Doroshkevich and A. Erhardt and G. J. Hofman and R. Meier and G. J. Wagner and G. Yaari},
journal= {arXiv preprint arXiv:nucl-ex/0404031},
year = {2009}
}
Comments
9 pages, 2 figures. Minor changes, to appear in PRL