Related papers: Rare radiative leptonic decays B_{d,s}-> l^+l^-\ga…
We obtain predictions for $B_{(s)}\to e^+e^-\gamma$ and $B_{(s)}\to \mu^+\mu^-\gamma$ decays. All the contributions containing long-distance QCD effects are calculated in the framework of relativistic quark model. The contributions of the…
We study the rare radiative leptonic decays $B_s\to\ell^+\ell^-\gamma$ ($\ell=e,\mu,\tau$) within the Standard Model, considering both the structure-dependent amplitude and bremsstrahlung. In the framework of the covariant confined quark…
In this work we study the radiative leptonic decays of $B^-$, $D^-$ and $D_s^-\to \gamma l \bar{\nu}$, including both the short-distance and long-distance contributions. The short-distance contribution is calculated by using the…
In the framework of the Standard Model we present predictions for partial widths, double and single differential distributions, and forward--backward lepton asymmetries for four-leptonic decays $B^- \to \mu^+\mu^- {\bar \nu}_e\, e^-$, $B^-…
We revisit rare radiative leptonic decays $B_{s,d}\to \gamma e^+e^-$ and $B_{s,d}\to \gamma \mu^+\mu^-$ in the Standard Model and provide the updated estimates for various differential distributions (the branching ratios, the…
We investigate the radiative dileptonic decays $B_s(B_d)\to\gamma l^+l^-$ within the standard model. Using the constituent quark model, the branching ratios turn out to be around $5\times 10^{-9}$ for $B_s\to \gamma \mu^+\mu^- $ and around…
We present first theoretical predictions for various observables related to the $\bar B_d \to \mu^+ \mu^- e^+ e^-$ decay within the framework of the Standard Model. Our study encompasses the branching ratios, differential distributions, and…
We analyse the long-distance contribution to $B\to X_s\ell^+\ell^-$ differential decay rate when the momentum dependence of $\psi$ and $\psi'$-$\gamma$ conversion strength is taken into account. The results indicate that the resonance to…
We study the rare radiative dileptonic decays $B^0(B_s)\to \gamma\ell^+\ell^-$ ($\ell=e,\mu$) in the standard model. By using the $B$ meson wave function constrained by non-leptonic decays, the branching ratios turn out to be of the order…
Long-distance effects in exclusive rare semileptonic transitions B -> (K, K*) are analysed within a relativistic quark model. The meson transition form factors, describing the meson amplitudes of the effective weak Hamiltonian, are…
In rare $B$ meson decays $B\rightarrow K \ell^+ \ell^-$, a possible contribution of $\ell^+\ell^-$ emission via photon from the "spectator" quark $q$ ($q=u,d$) in the $B$ meson $(q\bar{b})$ is investigated in addition to the conventional…
We investigate electromagnetic corrections to the rare $B$-meson leptonic decay $B_{s,d} \to \mu^+\mu^-$ from scales below the bottom-quark mass $m_b$. Contrary to QCD effects, which are entirely contained in the $B$-meson decay constant,…
Using the $B_s$ meson wave function extracted from non-leptonic $B_s$ decays, we evaluate the short distance contribution of rare decays $B_s\to \ell^+\ell^-\gamma(\ell=e,\mu)$ in the standard model, including all the possible diagrams. We…
We study long-distance effects in rare exclusive semileptonic decays B -> (K, K*) (l+ l-, nu bar{nu}) and analyze dilepton spectra and asymmetries within the framework of the Standard Model. The form factors, describing the meson transition…
This presentation reviews the main results of our recent work [A.K., D.M., N.N., Phys. Rev. D97, 053007 (2018)] on rare radiative leptonic decays $B_{d,s}\to\gamma\mu^+\mu^-$ and $B_{d,s}\to\gamma e^+e ^-$ induced by flavour-changing…
We compute the photon spectrum and the rate for the decays $B(D)\to l\nu_l\gamma$ These photonic modes constitute a potentially large background for the purely leptonic decays which are used to extract the heavy meson decay constants. While…
We present our recent results for long-distance QCD effects in the FCNC radiative leptonic decays $B\to\gamma\ell^+\ell^-$, $\ell=\{e,\mu\}$. One encounters here two distinct types of long-distance effects: those encoded in the $B\to\gamma$…
We calculate the differential branching fraction, lepton forward-backward asymmetry and direct CP asymmetry for $B_{d,s}\to\gamma\ell\bar{\ell}$ decays with an energetic photon. We employ factorization methods, which result in rigorous…
We report our ongoing lattice QCD study of radiative leptonic decays of the charged pseudoscalar mesons $D$, $D_s$, $B$, and $B_c \to \ell \nu_\ell \gamma$. We carry out our analysis on a single JLQCD ensemble with lattice spacing…
Adding a hard photon to the final state of a leptonic pseudoscalar-meson decay lifts the helicity suppression and can provide sensitivity to a larger set of operators in the weak effective Hamiltonian. Furthermore, radiative leptonic $B$…