相关论文: Chiral Dynamics and S-wave contributions in Semile…

The flavor-changing neutral current process $b\to s l^+l^-$ is beneficial to testing the standard model and hunting for new physics scenarios. In exclusive decay modes like $B\to K^*(892)l^+l^-$, the S-wave effects may not be negligible and…

Motivated by the LHCb measurement, we analyze the $B_s\to \pi^+\pi^-\ell^+\ell^-$ decay in the kinematics region where the pion pairs have invariant mass in the range $0.5$-$1.3$ GeV and muon pairs do not originate from a resonance. The…

The form factors of the semileptonic $B\to \pi\pi\ell\bar\nu$ decay are calculated from QCD light-cone sum rules with the distribution amplitudes of dipion states. This method is valid in the kinematical region, where the hadronic dipion…

We study the semileptonic $b\to u$ transition in the decay mode $B^-\to \pi^+\pi^-\ell^-\bar\nu_\ell$. We define $B\to \pi \pi$ form factors in the helicity basis, and study their properties in various kinematic limits, including form…

A new estimate is presented of the dileptonic $B$ decays $B\to\pi\ell^+\ell^-(\ell=e,\mu,\tau)$ in naive factorization within the standard-model (SM) framework. Using a combination of several approaches, we investigate the behavior of the…

In this work, we analyze the semi-leptonic decays $\bar B^0/D^0 \to (a_0(980)^{\pm}\to\pi^{\pm}\eta) l^{\mp} \nu$ within light-cone sum rules. The two and three-body light-cone distribution amplitudes (LCDAs) of the $B$ meson and the only…

We study $B\to\pi\pi$ form factors using QCD light-cone sum rules with $B$-meson distribution amplitudes. These form factors describe the semileptonic decay $B\to \pi\pi \ell\bar{\nu}_{\ell}$, and constitute an essential input in $B\to…

BELLE has recently reported the measurement of the branching fraction of the semileptonic $B^{-}\to\pi^{+}\pi^{-}\ell^{-}\bar\nu_\ell$ decay, where $\ell$ represents an electron or a muon. With the new information on the $\pi\pi$ invariant…

We provide new values for the model parameters of the covariant constituent quark model (with built--in infrared confinement) in the meson sector by a fit to the leptonic decay constants and a number of electromagnetic decays. We then…

We present a theoretical analysis of the $D^-\to \pi^+\pi^- \ell\bar\nu$ and $\bar D^0\to \pi^+\pi^0 \ell\bar\nu$ decays. We construct a general angular distribution which can include arbitrary partial waves of $\pi\pi$. Retaining the…

We analyse the $\overline B_s^0\to K^+l^-\bar \nu$ and $\overline B_s^0\to K^{*+}(\to K\pi) \ell^-\bar \nu$ decays that are valuable for extracting the CKM matrix element $|V_{ub}|$. We calculate the differential and integrated partial…

We update the lattice calculation of the $B\to\pi$ semileptonic form factors, which have important applications to the CKM matrix element $|V_{ub}|$ and the $B\to\pi\ell^+\ell^-$ rare decay. We use MILC asqtad ensembles with $N_f=2+1$ sea…

Coupled-channel effects are taken into account for the study of scalar form factors in semi-leptonic $D\to\pi\bar{\ell}\nu_\ell$ and $D\to \bar{K}\bar{\ell}\nu_\ell$ decays, by solving the Muskhelishvili-Omn\`es integral equations. As…

In this paper we first calculate the form factors of $B \to (\pi,K)$ and $B_s \to K $ transitions by employing the perturbative QCD (pQCD) factorization approach with the inclusion of the next-to-leading-order(NLO) corrections, and then we…

The form factors of semileptonic $B_{(s)}\to a_{1}(K_1)\, \ell^{+}\ell^{-}$, $ \ell=\tau,\mu,e$ transitions are investigated in the framework of the light-cone sum rules with $B$-meson distribution amplitudes, which play an important role…

The transition form factors of $B_{(s)} \to S$, with $S$ denoting a scalar meson, are investigated in the light-cone sum rules approach. The numerical values are approximately twice as large as that estimated in the light-front quark model…

In the wake of the recent measurements of the decays $B_c\to J/\psi\,\pi(K)$ and $B_c\to J/\psi\,\ell\nu_\ell$ reported by the LHCb Collaboration we calculate the form factors for the $B_c\to J/\psi$ and $B_c\to \eta_{c}$ transitions in…

In the $\rm SU(3)_F$ symmetry limit, using two- and three-particle distribution amplitudes of $B^{\pm}$-meson for $B_s$, the transition form factors of semileptonic $B_{s}\to K_{0}^*(1430)$ decays are calculated in the framework of the…

We perform a combined study of the two hadronic decays $D^+\to K^-\pi^+\pi^+$ and $D_s^+\to K^+K^+\pi^-$ using a detailed analysis of the semileptonic decays $D^+\to K^-\pi^+ \ell^+\nu_\ell$ ($\ell=e, \mu$) thanks to the high-statistics…

Semileptonic $B$($B_s, B_c$) decays are investigated systematically in the light-cone QCD sum rules. Special emphasis is put on the LCSR calculation on weak form factors with an adequate chiral current correlator, which turns out to be…