On heavy-light meson resonances and chiral symmetry

We study heavy-light meson resonances with quantum numbers JP = 0+ and JP = 1+ in terms of the non-linear chiral SU(3) Lagrangian. At leading order a parameter-free prediction is obtained for the scattering of Goldstone bosons off heavy-light pseudo-scalar and vector mesons once we insist on approximate crossing symmetry of the unitarized scattering amplitude. The recently announced narrow open charm states observed by the BABAR and CLEO collaborations are reproduced. We suggest the existence of states that form an anti-triplet and a sextet representation of the SU(3) group. In particular, so far unobserved narrow isospinsinglet states with negative strangeness are predicted. The open bottom states with (I, S) = (0,−1) are anticipated at 5761 MeV (JP =0+) and 5807 MeV (JP =1+). For the anti-triplet states our results differ most significantly from predictions that are based on a linear realization of the chiral SU(3) symmetry in the open bottom sector. Strongly bound 0+-and 1+-states with (I, S) = (0, 1) at 5643 MeV and 5690 MeV are predicted.