Charm meson resonances andD→Vsemileptonic form factors

Abstract

Using limits of large energy effective theory and heavy quark effective theory we propose a simple parametrization of the heavy to light H → V semileptonic form factors. Then we reconsider D → V ℓν ℓ decays within a model which combines heavy meson and chiral symmetry. In our Lagrangians we include contributions coming from excited charm meson states, some of them recently observed. Within this framework we determine all parameters describing the shapes of the form factors and calculate branching ratios and helicity ratios for all D → V ℓν ℓ decays.

First Measurement of the Form Factors in the DecaysD0→ρ−e+νeandDobbs1, Metreveli2, Seth3 et al. 2013Phys. Rev. Lett.291280View full textAdd to dashboardCite

“…We have also explored a double-pole parametrization [3]. We report herein the first measurement of the form factor ratios and absolute form factor normalization in D → ρe + ν e , and improved branching fraction measurements for these decays and D + → ωe + ν e .…”

“…They are not amenable to unquenched LQCD calculations due to the large total decay width of the ρ meson, but model predictions exist [2,3]. No experimental information on these form factors exists.…”

“…Its magnitude is taken as the uncertainty due to possible bias in the form factor fitter (0.03, 0.02). The uncertainty associated with the unknown q 2 dependence of the form factors (0.03, 0.02) is estimated by introducing a second pole [3].…”

“…Due to the finite resolution of the detector, the distribution in U is approximately Gaussian, with resolution ∼17 MeV for D 0 → ρ − e + ν e and D + → ωe + ν e and ∼8 MeV for D + → ρ 0 e + ν e . [10], and two model predictions: ISGW2 [2] and FK [3]. All B SL are in units of 10 −3 .…”

Analysis of theD+→K−π+e+νedecay channel

“…Other parameterizations involving a double pole in V have been proposed [33], but as the present analysis is not sensitive to m V , the single pole ansatz is adequate.…”