Related papers: Study of $b\to c$ induced $\bar{B}^* \to V \ell \b…

We determine the CKM matrix-element magnitude $|V_{cb}|$ using $\overline{B}^0\to D^{*+}\ell^-\bar\nu_\ell$ decays reconstructed in $189 \, \mathrm{fb}^{-1}$ of collision data collected by the Belle II experiment, located at the SuperKEKB…

The semileptonic $B$ meson decays of the type $B \to X_u \ell \nu$ are important for measuring the magnitude of the CKM matrix element $V_{ub}$. Recent measurements of inclusive $B \to X_u e \nu_e$ and hadronically tagged $B^0 \to \pi^-…

The measured $\bar{B}\to D^{(*)} l \bar\nu$ decay rates for light leptons ($l=e,\mu$) constrain all $\bar{B}\to D^{(*)}$ semileptonic form factors, by including both the leading and ${\cal O}(\Lambda_{\text{QCD}}/m_{c,b})$ subleading…

To the leading order, the radiative leptonic decays $B_c \to \gamma \ell \bar \nu$ ($ \ell=e, \mu$) are studied carefully. In the study, a non-relativistic constituent quark model and the effective Lagrangian for the heavy flavour decays…

We analyze the semileptonic $B \to a_1 \ell^+\ell^-$, $\ell=\tau, \mu, e$ transitions in the frame work of the three-point QCD sum rules in the standard model. These rare decays governed by flavor-changing neutral current transition of $b…

We comprehensively study the charged-Higgs contributions to the leptonic $B^-_q \to \ell \bar \nu$ ($q=u,c$) and semileptonic $\bar B \to X_q \ell \bar\nu$ ($X_u=\pi, \rho; X_c=D,D^*$) decays in the type-III two-Higgs-doublet model (2HDM).…

We fit the available data on exclusive semileptonic $b\to u\ell^-\bar\nu$ decays within the Standard Model and in the Weak Effective Theory. Assuming Standard Model dynamics, we find $|V_{ub}| = 3.59^{+0.13}_{-0.12} \times 10^{-3}$. Lifting…

The $B_{c}^{\ast}$ ${\to}$ $B_{u,d,s}V$, $B_{u,d,s}P$ decays are investigated with the QCD factorization approach, where $V$ and $P$ denote the ground $SU(3)$ vector and pseudoscalar mesons, respectively. The $B_{c}^{\ast}$ ${\to}$…

The bounds on the form factors for $B \to \rho \ell \nu_\ell$ decay are studied. Constrained by lattice data and a constrained conformal mapping, the more informations can be obtained for $A_1(q^2)$ form-factor which dominates the decay…

We derive the four-fold angular distribution for the semileptonic decay $\bar{B}\to D_2^*(\to D \pi)\,\ell \bar{\nu}$ where $D_2^*$(2460) is a tensor meson. We start with the most general beyond the Standard Model (SM) dimension-six…

Using dispersive methods, we study the $B \to \gamma^*$ form factors underlying the decay $B^- \to \ell^- \bar{\nu}_\ell \ell^{\prime-} \ell^{\prime+}$. We discuss the ambiguity that arises from a separation of the full $B^- \to \ell^-…

We study inclusive semileptonic $\bar{B}\to X_c \ell \bar{\nu}$ decays ($\ell = e,\mu$) in the presence of generic physics Beyond the Standard Model (BSM) that is heavy compared to the $b$-quark mass. Its effect is encoded in the Wilson…

In this work, we have conducted a comprehensive and systematic theoretical investigation of the full cascade decays of charged pseudoscalar mesons, specifically $D_s$, $D$, $B$, and $B_c$, into $\tau \nu_\tau$, followed by the subsequent…

We extend the Standard Model (SM) analysis of Ref. [1], which was limited to light leptons in the final state, to the semileptonic $B \to D^* \tau \nu_\tau$ decay. By using quantities that can be analised without the knowledge of $\vert…

In this work we compute the branching fraction of $B \to D^{(*)} \,\tau \, \nu_{\tau}$ and $B_s \to D_s^{(*)}\, \tau\, \nu_{\tau}$ within the Relativistic Independent Quark Model, emphasizing the harmonic potential model dependent analysis…

The weak decays of B_{c} --> D_{s}^{*}l^{+}l^{-} (l=mu,tau) are investigated in the Standard Model with fourth generation (SM4). Taking fourth generation quark mass m_{t'} of about 300 to 600 GeV with the CKM matrix elements…

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 study the decays of $B_{s,d} \to l^+ l^- \gamma (l=e, \mu,\tau)$ within the light-front model. We calculate the tensor type form factors and use these form factors to evaluate the decay branching ratios. We find that, in the standard…

The recent observation of the purely leptonic decay B^\pm\to \tau^\pm\nu_\tau at the B factories permits a sizeable contribution from a charged Higgs boson (H^\pm). Such a H^\pm would also contribute to the decays D^\pm_s\to \mu^\pm\nu_\mu…

Our article is devoted to the study of the rare $B\to K^\ast \ell^+\ell^-$~decay where $\ell=e,\mu,\tau$. We compute the relevant form factors in the framework of the covariant quark model with infrared confinement in the full kinematical…