Dynamically generated 0^+ heavy mesons in a heavy chiral unitary approach

Abstract

In terms of the heavy chiral Lagrangian and the unitarized coupled-channel scattering amplitude, interaction between the heavy meson and the light pseudoscalar meson is studied. By looking for the pole of scattering matrix on an appropriate Riemann sheet, a $DK$ bound state $D_{s0}^{\ast }$ with the mass of $2.312\pm 0.041$ GeV is found. This state can be associated as the narrow $D_{sJ}^{\ast }(2317)$ state found recently. In the same way, a $B\bar{K}$ bound state $B_{s0}^{\ast }$ is found, and its mass of $5.725\pm 0.039$ GeV is predicted. The spectra of $D_0^{\ast }$ and $B_0^{\ast }$ with $I=1/2$ are further investigated. One broad and one narrow states are predicted in both charm and bottom sectors. The coupling constants and decay widths of the predicted states are also calculated.

15 pages, 1 figure. One numerical error in Eq.16 corrected

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