Hadronic-loop induced mass shifts in scalar heavy-light mesons

Abstract

We calculate the mass shifts of heavy-light scalar mesons due to hadronic loops under the assumption that these vanish for the groundstate heavy-light mesons. The results show that the masses calculated in quark models can be reduced significantly. We stress that the mass alone is not a signal for a molecular interpretation. Both the resulting mass and the width suggest the observed $D_0^{\ast }$ state could be a dressed $c\bar{q}$ state. We give further predictions for the bottom scalar mesons which can be used to test the dressing mechanism.

Comments: 14 pages, 2 figures. Version accepted for publication in Phys. Lett. B