Overview of pion-nucleus interaction at low energies

Abstract

Predictions of the existence of well-defined deeply bound pionic atom states for heavy nuclei and the eventual observation of such states by the (d,3He) reaction have revived interest in the pion-nucleus interaction at threshold and in its relation to the corresponding pion-nucleon interaction. Explanation of the 'anomalous' s-wave repulsion in terms of partial restoration of chiral symmetry and/or in terms of energy-dependence effects have been tested in global fits to pionic atom data and in a recent dedicated elastic scattering experiment. The role of neutron density distributions in this context is discussed in detail for the first time.

arXiv comment8 pages, 4 figures, MESON2006 Workshop, to appear in Int. J. Modern Phys. A

References in corpus (4)

• Antiproton-nucleus potentials from global fits to antiprotonic X-rays and radiochemical data
• The in-medium isovector pi N amplitude from low energy pion scattering
• Elastic scattering of low energy pions by nuclei and the in-medium isovector pi N amplitude
• Renormalization of the isovector $\pi N$ amplitude in pionic atoms