Related papers: Semileptonic $\Lambda_{b}\rightarrow \Lambda_{c}{\…
We present a reconstruction in early data of the semileptonic decay $B^+ \to \pi^0 \ell^+ \nu_\ell$, and first results of a reconstruction of the decays $B^+ \to \rho^0 \ell^+ \nu_\ell$ and $B^0 \to \rho^- \ell^+ \nu_\ell$ in a sample…
We study the differential decay rate for the rare $\Lambda_b \to \Lambda (\to N \pi)\ell^+\ell^-$ transition, including a determination of the complete angular distribution, assuming unpolarized $\Lambda_b$ baryons. On the basis of a…
Recently there has been much interest in the tauonic semileptonic meson decays B -> D + tau + nu_tau and B -> D* + tau + nu_tau where one has found larger rates than what is predicted by the Standard Model. We analyze the corresponding…
In this contribution we present a novel, model-independent description of semileptonic $B\rightarrow D \pi \ell \nu$ decays. In addition, we discuss recent developments in the understanding of coupled-channel $D \pi$-$D \eta$-$D_s K$ S-wave…
Measurements of the branching ratios of $B \to D^{(*)}\tau\bar\nu/B \to D^{(*)}\ell\bar\nu$ and $B_c\to J/\psi\, \tau\bar\nu/B_c\to J/\psi\, \ell\bar\nu$ by the BaBar, Belle and LHCb collaborations consistently point towards an abundance of…
Experimental data on $ R(D^{(*)}) $, $ R(K^{(*)}) $ and $ R(J/\psi) $, provided by different collaborations, show sizable deviations from the SM predictions. To describe these anomalies many new physics scenarios have been proposed. One of…
We study the semileptonic decay $\bar{B}_s \to K^{*+} \ell^-\bar\nu_\ell$, which is induced by $b\to u \ell^- \bar\nu_\ell$ transitions at the quark level. We take into account the standard model (SM) operator from $W$-boson exchange as…
The leading Isgur-Wise form factor $\xi(y)$ parametrizing the semileptonic transitions $\Lambda_b\to\Lambda^{1/2}_{c1}\ell\bar\nu$ and $\Lambda_b\to\Lambda^{3/2}_{c1}\ell\bar\nu$ is calculated by using the QCD sum rules in the framework of…
We present estimates of the semileptonic widths of the $B_s$ and $\Lambda_b$ hadrons. We employ the latest fit to the $B$ inclusive semileptonic data, the heavy quark expansion and lattice QCD results. Our results suffer from large…
Based on the predictions of the relevant form factors from the covariant light-front quark model, we show the branching fractions for the $D (D_s) \to (P,\,S,\,V,\,A)\,\ell\nu_\ell$ ($\ell=e$ or $\mu$) decays, where $P$ denotes the…
Understanding the properties of the strange $\Lambda^*$ baryon resonances is a long-standing and fascinating problem. $\Lambda_c$ charm-baryon semileptonic weak decays to these resonances are highly sensitive to their internal structure and…
We study the semileptonic transitions B_c to \eta_c, J/\psi, D, D^*, B, B^*, B_s, B_s^* in the framework of a relativistic constituent quark model. We use experimental data on leptonic J/\psi decay, lattice and QCD sum rule results on…
We report our theoretical calculations on the branching fractions for the semileptonic $B$ and $B_s$ decays, i.e., $B (B_s) \to (P,\, V,\, S,\,A) \ell \nu_\ell$, where $P$ and $V$ denote the pseudoscalar and vector mesons, respectively,…
The form factors of the semileptonic $B$, $B_s$ and $B_c$ meson decays are calculated in the framework of the relativistic quark model based on the quasipotential approach in QCD. They are expressed through the overlap integrals of the…
We apply the general formalism derived in N. Penalva et al. [Phys. Rev. D 101, 113004 (2020)] to the semileptonic decay of pseudoscalar mesons containing a $b$ quark. While present $B\to D^{(*)}$ data give the strongest evidence in favor of…
We present measurements of the semileptonic decays B- --> D0 tau- nubar_tau, B- --> D*0 tau- nubar_tau, B0bar --> D+ tau- nubar_tau, and B0bar --> D*+ tau- nubar_tau, which are sensitive to non--Standard Model amplitudes in certain…
We comparatively analyze the flavor changing neutral current process of the $\Lambda_b \rightarrow \Lambda \ell^+ \ell^-$ in the standard model as well as topcolor-assisted technicolor model using the form factors calculated via light cone…
We study the semileptonic decays ${\bf B_c} \to {\bf B_n} \ell^+ \nu_{\ell}$ where ${\bf B_{c(n)}}$ is the anti-triplet-charmed (octet) baryon with the $SU(3)_f$ flavor symmetry and helicity formalism. In particular, we present the decay…
We perform a detailed analysis of semileptonic $\Xi_b$ decays mediated by flavor-changing neutral currents ($b\to s$ and $b\to d$) with dilepton or dineutrino final states within the perturbative QCD framework. All independent form factors…
The form factors of the weak $\Xi_c\to \Xi(\Lambda)$ transitions are calculated in the framework of the relativistic quark model based on the quasipotential approach. All relativistic effects including transformations of the baryon wave…