Statut | Confirmé |
Série | IPN-X |
Domaines | hep-ph |
Date | Jeudi 8 Novembre 2018 |
Heure | 11:00 |
Institut | CPHT |
Salle | Salle de Conferences Louis Michel, bat. 6, CPHT, Ecole polytechnique |
Nom de l'orateur | Pham |
Prenom de l'orateur | Tri Nang |
Addresse email de l'orateur | |
Institution de l'orateur | CPHT, Ecole polytechnique |
Titre | Heavy to Light Meson Semileptonic Decays Form Factors |
Résumé | Like the two-photon and two-gluon decays of the $P$-wave $\chi_{c0,2}$ and $\chi_{b0,2}$ state for which the Born term produces a very simple decays amplitude in terms of an effective Lagrangian with two-quark local operator, the Born term for the processes $c\bar{d}\to(\pi,K)\ell\nu $ and $b \bar{d}\to(\pi, K)\ell\nu $, could also produce the $D$ and $B$ meson semileptonic decays with the light meson $\pi, K$ in the final state. In this approach to heavy-light meson form factors with the $\pi, K$ meson treated as Goldstone boson, a simple expression is found for the decays form factors, given as~: $f_{+}(0)/(1-q^{2}/(m_{H}^{2}+m_{\pi}^{2}))$, with $H=D,B$ for $D,B\to\pi$ form factors, and $f_{+}(0)/(1-q^{2}/(m_{H}^{2}+ m_{K}^{2}))$ for $B, D\to K$ form factor. In this talk, I would like to present a recent work showing that this expression for the form factors could describe rather well the $q^{2}$-behaviour observed in the BaBar, Belle and BESSIII measurements and lattice simulation. In particular, the $D\to K$ form factors are in good agreement with the measured values in the whole range of $q^{2}$ showing evidence for $SU(3)$ breaking with the presence of $m_{K}^{2}$ term in the quark propagator, but some corrections to the Born term are needed at large $q^{2}$ for $D, B\to\pi$ form factors. |
Numéro de preprint arXiv | |
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