出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We investigate the quark mass dependence of meson and baryon masses obtained from 2+1 flavor
dynamical quark simulations performed by the PACS-CS Collaboration. With the use of SU(2)
and SU(3) chiral perturbation theories up to NLO, we examine the chiral behavior of the pseudoscalar
meson masses and the decay constants in terms of the degenerate up-down quark mass
ranging form 3 MeV to 24 MeV and two choices of the strange quark mass around the physical
value. We discuss the convergence of the SU(2) and SU(3) chiral expansions and present the
results for the low energy constants. We find that the SU(3) expansion is not convergent at NLO
for the physical strange quark mass. The chiral behavior of the nucleon mass is also discussed
based on the SU(2) heavy baryon chiral perturbation theory up to NNLO. Our results show that
the expansion is well behaved only up to m2p 0
2 GeV2.
