Schwinger functions and light-quark bound states, and sigma terms
Abstract
We explore the viability of using solely spacelike information about a Schwinger function to extract properties of bound states. In a concrete example it is not possible to determine properties of states with masses \gsim 1.2 GeV. Modern Dyson-Schwinger equation methods supply a well-constrained tool that provide access to hadron masses and \sigma-terms. We report values of the latter for a range of hadrons. Of interest is analysis relating to a u,d scalar meson, which is compatible with a picture of the lightest 0^{++} as a bound state of a dressed-quark and -antiquark supplemented by a material pion cloud. A constituent-quark \sigma-term is defined, which affords a means for assessing the flavour-dependence of dynamical chiral symmetry breaking.
Keywords
Cite
@article{arxiv.nucl-th/0512048,
title = {Schwinger functions and light-quark bound states, and sigma terms},
author = {A. Hoell and P. Maris and C. D. Roberts and S. V. Wright},
journal= {arXiv preprint arXiv:nucl-th/0512048},
year = {2008}
}
Comments
To appear in the proceedings of Workshop on Light-Cone QCD and Nonperturbative Hadron Physics 2005 (LC 2005), Cairns, Queensland, Australia, 7-15 Jul 2005