出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We present preliminary results for the chiral behavior of charged pseudo-Goldstone-boson masses
and decay constants. These are obtained in simulations with Nf=2+1 flavors of tree-level, O(a)-
improvedWilson sea quarks. In these simulations, mesons are composed of either valence quarks
discretized in the same way as the sea quarks (unitary simulations) or of overlap valence quarks
(mixed-action simulations). We find that the chiral behavior of the pseudoscalar meson masses in
the mixed-action calculations cannot be explained with continuum, partially-quenched chiral perturbation
theory. We show that the inclusion of O(a2) unitarity violations in the chiral expansion
resolves this discrepancy and that the size of the unitarity violations required are consistent with
those which we observe in the zero-momentum, scalar-isotriplet-meson propagator.
