Ds0∗(2317) and DK scattering in B decays from BaBar and LHCb data

Abstract

We study the experimental DK invariant mass spectra of the reactions [InlineEquation not available: see fulltext.], B0→ D-D0K+ (measured by the BaBar collaboration) and Bs→ π+D¯ 0K- (measured by the LHCb collaboration), where an enhancement right above the threshold is seen. We show that this enhancement is due to the presence of Ds0∗(2317), which is a DK bound state in the I(JP) = 0 (0 +) sector. We employ a unitarized amplitude with an interaction potential fixed by heavy meson chiral perturbation theory. We obtain a mass MDs0∗=2315-17+12-5+10MeV, and we also show, by means of the Weinberg compositeness condition, that the DK component in the wave function of this state is PDK=70-6+4-8+4%, where the first (second) error is statistical (systematic).