1 Physik-Department, Technische Universität München, D-85747 Garching,
2 Research Institute for Basic Sciences and Department of Physics, Seoul National University, Seoul 151-742, Korea
3 Physik-Department, Technische Universität München, D-85747 Garching, Germany
Received: 29 June 1998 / Revised version: 25 November 1998 Communicated by A. Schäfer
We analyse the baryon mass spectrum in a framework which combines the 1/Nc expansion with chiral perturbation theory. Meson loop contributions involving the full SU(3) octet of pseudoscalar Goldstone bosons are evaluated, and the influence of explicit chiral and flavor symmetry breaking by non-zero and unequal quark masses is investigated. We also discuss sigma terms and the strangeness contribution to the nucleon mass.
14.20.-c Baryons (including antiparticles) - 11.15.Pg Expansions for large numbers of components (e.q., 1/Nc expansions) - 12.39.Fe Chiral Lagrangians