Chiral effective theory with a light scalar and lattice QCD
Abstract
We extend the usual chiral perturbation theory framework (PT) to allow the inclusion of a light dynamical isosinglet scalar. Using lattice QCD results, and a few phenomenological inputs, we explore the parameter space of the effective theory. We discuss the S-wave pion-pion scattering lengths, extract the average value of the two light quark masses and evaluate the impact of the dynamical singlet field in the low--energy constants , and of PT. We also show how to extract the mass and width of the sigma resonance from chiral extrapolations of lattice QCD data.
Keywords
Cite
@article{arxiv.1110.6156,
title = {Chiral effective theory with a light scalar and lattice QCD},
author = {J. Soto and P. Talavera and J. Tarrús},
journal= {arXiv preprint arXiv:1110.6156},
year = {2015}
}
Comments
Journal version. Added the study of the scalar two-point function and a discussion of the analytical properties of the sigma pole and its dependence on the quark masses. We clarified the relation of $chi$PT$_S$ with unitarized $chi$PT. Figures 6 and 8 have been improved. 28 pages, 2 tables, 8 figures