Charm meson resonances in D→Pℓν decays

Motivated by recent experimental results we reconsider semileptonic D→Pℓν_ℓ decays within a model which combines heavy quark symmetry and properties of the chiral Lagrangian. We include excited charm meson states, some of them recently observed, in our Lagrangian and determine their impact on the charm meson semileptonic form factors. We find that the inclusion of excited charm meson states in the model leads to a rather good agreement with the experimental results on the q² shape of the F₊(q²) form factor. We also calculate branching ratios for all D→Pℓν_ℓ decays.