Chiral loop corrections to strong decays of positive and negative parity charmed mesons

We consider chiral loop corrections to the effective couplings which describe the strong interactions of two heavy mesons of even or odd parities and a light pseudoscalar meson, within a framework which combines heavy quark effective theory and chiral perturbation theory. The strong couplings are extracted from the experimental results for the decay widths, after including chiral corrections. We find that the introduction of positive parity heavy meson fields into the framework gives relevant contributions to the chiral loop corrections of the effective couplings. The counterterms' contributions are studied by making a randomized fit distribution of the relevant couplings at mu = 1 GeV. Then we discuss the chiral extrapolation based on calculated loop contributions. The inclusion of positive parity mesons in the chiral loops is found to be important for the lattice QCD studies of charm meson properties, where the knowledge of chiral limit behavior is required.