Light meson mass dependence of the positive-parity heavy-strange mesons

We calculate the masses of the resonances D*(s0)(2317) and D(s1)(2460) as well as their bottom partners as bound states of a kaon and a D(()*())-and B(()*())-meson, respectively, in unitarized chiral perturbation theory at next-to-leading order. After fixing the parameters in the D*(s0)(2317) channel, the calculated mass for the D(s1)(2460) is found in excellent agreement with experiment. The masses for the analogous states with a bottom quark are predicted to be MB*(s0) - (5696 +/- 40) MeV and M(Bs1) - (5742 +/- 40) MeV in reasonable agreement with previous analyses. In particular, we predict M(Bs1)-MB*(s0) - 46 +/- 1MeV. We also explore the dependence of the states on the pion and kaon masses. We argue that the kaon mass dependence of a kaonic bound state should be almost linear with slope about unity. Such a dependence is specific to the assumed molecular nature of the states. We suggest to extract the kaon mass dependence of these states from lattice QCD calculations.