Related papers: Testing Lepton Flavour Universality with (Semi)-Le…
We show how to extract the Cabibbo-Kobayashi-Maskawa (CKM) matrix element $\vert V_{cb} \vert$ from exclusive semileptonic $B \to D^{(*)}$ decays by using the Dispersive Matrix (DM) method. It is a new approach which allows to determine in…
The semi-leptonic $b \to c l \nu$ processes are receiving a lot of attention, as the lepton flavor universality violation has been hinted by the measured ratios $R_{D^{(*)}} = \Gamma(B \to D^{(*)} \tau\nu)/\Gamma(B \to D^{(*)} \ell\nu)$ for…
We present a systematic survey of possible short-distance new-physics effects in (semi)leptonic charged- and neutral-current charmed meson decays. Using the Standard Model Effective Field Theory (SMEFT) to analyze the most relevant…
Experimental measurements of different decays of charmed mesons have been extensively performed at BESIII. Precision measurements of absolute branching fractions of different decays, the decay constants of $D^+$ and $D^+_s$ mesons, hadronic…
Considering the recent experimental results on exclusive semileptonic $B$ meson decays showing sizable departure from their Standard Model prediction of lepton flavor universality and keeping ongoing and proposed non-standard Higgs searches…
One important task in the field of flavor physics is to over-constrain the CKM matrix. To best extract CKM matrix elements, we need inputs from both experimental data and theoretical calculations. Latest knowledge about the CKM matrix shows…
In this work, we discuss exclusive semileptonic $B_c$-meson decays: $B_c\to \eta_c(J/\psi)l\nu$ and $B_c\to D(D^*)l\nu$ in the framework of the relativistic independent quark(RIQ) model based on an average flavor independent confining…
We construct a semi-inclusive Lepton Flavour Universality (LFU) ratio, $R_\Sigma$, to test $\mu/e$ universality in $b\to s\ell^+\ell^-$ transitions at $e^+e^-$ $B$-meson factories. Combining different decay channels, this observable…
The recent measurements on $R_K$ and $R_{\pi}$ imply that there exists a possible violation of the leptonic flavor universality which is one of the cornerstones of the standard model. It is suggested that a mixing between sterile and active…
In the wake of recent measurements of ratios of semileptonic branching fractions: ${\cal R}_{J/\psi}, {\cal R}_D$ and ${\cal R}_{D^*}$ reported by the LHCb, BELLE and HFLAV Collaborations, we calculate invariant form factors for the…
Motivated by more precise recent measurements of the $B \to \eta \ell \nu$ and $D_{(s)} \to \eta^{(\prime)}\ell \nu$ decays, we employ state-of-the-art parametrizations to describe the $B_{(s)}, D_{(s)} \to \eta^{(\prime)}$ form factors…
Lepton flavor universality can be tested through the ratio of semileptonic $B$ meson decays and leptonic $\Upsilon$ meson decays, with $\Upsilon \equiv \Upsilon(nS)$ ($n=1,2,3$). For the charged-current transitions $b \to…
We present some results of the {\bf{ELC}} (European Lattice Collaboration) study of leptonic and semi-leptonic decays of heavy-light mesons. Results on the decay constants $f_D, f_{D_s}$ and $f_B, f_{B_s}$, the semi-leptonic form factors of…
Among (semi)leptonic rare $B$-decays induced by the $b \to d$ flavor changing neutral current, the decay $B^+ \to \pi^+ \mu^+ \mu^-$ is the only one observed so far experimentally. Related decays involving the $e^+e^-$ and $\tau^+ \tau^-$…
Inspired by the newly reported $B\to D^*(\to D\pi)\ell\bar{\nu}_\ell$ differential decay rates by the Belle and Belle II Collaborations, we revisit the $V_{cb}$ puzzle in semi-leptonic $B\to D^*$ decays, considering the latest lattice…
Using e+e- collision data in the sqrt{s} = 4 GeV energy region, CLEO-c has made extensive studies of semileptonic and leptonic decays of the D0, D+, and Ds+ charmed mesons. We report recent measurements of absolute branching fractions, form…
Semileptonic decays of charged and neutral $B$ mesons play a critical role in the determination of the magnitudes of the CKM-matrix elements $V_{cb}$ and $V_{ub}$, and in the test of the lepton universality which is a basic assumption of…
We benefit from a recent lattice determination of the full set of vector, axial and tensor form factors for the $\Lambda_b\to \Lambda^*_c(2595)\tau\bar\nu_\tau$ and $\Lambda^*_c(2625)\tau\bar\nu_\tau$ semileptonic decays to study the…
It has been shown that the anomalies observed in $\bar B\to D^{(\ast)}\tau\bar\nu_\tau$ and $\bar B\to \bar K\ell^+\ell^-$ decays can be resolved by adding a single scalar or vector leptoquark to the Standard Model, while constraints from…
The evidence for Lepton Flavour Universality (LFU) violation in semileptonic $B$-decays has been rising over the past few years. Relying on generic effective field theory (EFT) results, it has been shown that models addressing the…