Spectrum and Decays of Hadronic Atoms
High Energy Physics - Phenomenology
2011-04-15 v1
Abstract
Using non relativistic effective Lagrangian techniques, we analyze the hadronic decay of the pi+pi- atom and the strong energy-level shift of pionic hydrogen in the ground state. We derive general formulae for the width and level shift, valid at next-to-leading order in isospin breaking. The result is expressed in terms of hadronic threshold amplitudes that include isospin-breaking effects. In order to extract isospin symmetric scattering lengths from the data, we invoke chiral perturbation theory, that allows one to relate the scattering lengths to the threshold amplitudes.
Keywords
Cite
@article{arxiv.hep-ph/9911260,
title = {Spectrum and Decays of Hadronic Atoms},
author = {J. Gasser and V. E. Lyubovitskij and A. Rusetsky},
journal= {arXiv preprint arXiv:hep-ph/9911260},
year = {2011}
}
Comments
8 pages. Talk given at ``8th International Symposium on Meson-Nucleon Physics and the Structure of the Nucleon (MENU99)'', Zuoz, Switzerland, August 16-20, 1999