Related papers: Radiative Dileptonic Decays of B Mesons
B-meson decays are very useful probes for testing the Standard Model and its various extensions. Leptonic decays of B have very clean signatures in this respect and hence can be very useful testing grounds. In this work we study the effects…
Based on $10.64~\mathrm{fb}^{-1}$ of $e^+e^-$ collision data taken at center-of-mass energies between 4.237 and 4.699 GeV with the BESIII detector, we study the leptonic $D^+_s$ decays using the $e^+e^-\to D^{*+}_{s} D^{*-}_{s}$ process.…
We determine the relative branching fractions of semileptonic B decays to charmed final states. The measurement is performed on the recoil from a fully reconstructed B meson in a sample of 362 million BBbar pairs collected at the…
A measurement of the ratio of the branching fractions of the $B^{+}\rightarrow K^{+}\mu^{+}\mu^{-}$ and $B^{+}\rightarrow K^{+}e^{+}e^{-}$ decays is presented using proton-proton collision data, corresponding to an integrated luminosity of…
The rare decays $B_{(s,d)}^*\to l^+ l^-$ are important to probe the flavour sector of the standard model and to search new physics beyond the SM. Unlike pseudoscalar B meson, the leptonic decays of vector $ B_(s,d)^*$ mesons are not…
We observe the radiative decay $D^{*}_{s0}(2317)^{+} \to D_{s}^{*+} \gamma$ for the first time, with a significance exceeding $10$ standard deviations. The signal is found in the continuum $e^+ e^- \to c\bar{c}$ process with the combined…
The branching fractions of radiative leptonic $\tau$ decays $(\tau \to l \nu \bar{\nu} \gamma$, $l=e,\mu)$ were recently measured by the Babar collaboration with a relative error of about 3%. The measurement of the branching ratio…
We use QCD sum rules to estimate the leading-order universal form factors describing the semileptonic B decay into orbital excited $D$-wave charmed doublets, including the ($1^{-}$, $2^{-}$) states ($D_{1}^{*}$, $D'_{2}$) and the ($2^{-}$,…
Pure leptonic radiative decays of heavy-light mesons are calculated using a very simple non-relativistic model. Dominant contribution originates from photon emission from light initial quark. We find…
We propose a new method to extract |Vtd/Vts| from the ratio of the decay distributions dR/ds = dB(B->Xdl+l-)/ds/dB(B->Xsl+l-)/ds. This ratio depends only on the KM ratio |Vtd/Vts| with 15% theoretical uncertainties, if dilepton invariant…
We present a study of B semileptonic decays into charm final states based on 211.7 fb^{-1} of data collected at the \Upsilon(4S) resonance with the babar detector at the pep2 e^+e^- storage ring. Using a novel technique based on the…
We measure the absolute branching fractions of semileptonic $D^+_s$ decays via the $e^+e^-\to D_s^{*+}D_s^{*-}$ process using $e^+e^-$ collision data corresponding to an integrated luminosity of $10.64~\mathrm{fb}^{-1}$ collected by the…
The semileptonic decays $\bar{B}\to D(D^*)\pi\ell\bar{\nu}$ are analyzed by heavy quark and chiral symmetries. The branching ratio is of order of a few percent for $\dpi$, but it is much smaller for $\dstar$, of order $10^{-4}-10^{-5}$. The…
We analyze the semileptonic (B_c -> B_u* l+ l-) decay in the frame work of the Standard Model. We calculate the (B_c) to (B_u*) transition form factors in QCD sum rules. Analytical expressions for the spectral densities and gluon…
The branching fraction of the rate decay $B^0 \rightarrow K^{*0}e^+e^-$ in the dilepton mass region from 30 to 1000 MeV$/c^2$ has been measured by the LHCb experiment, using $pp$ collision data, corresponding to an integrated luminosity of…
Using the relativistic Bethe-Salpeter method, the electron energy spectrum and the semileptonic decay widths of $B^0_s\to D^-_s \ell^+{\nu_\ell}$ and $B^0_s\to D_s^{*-}\ell^+{\nu_\ell}$ are calculated. We obtained large branching ratios,…
Within the standard model, we calculate the radiative $B\rightarrow K^{\star}\gamma$ decay rate based on a Bethe-Salpeter description for the meson wave functions and the hadronic matrix elements. With a reasonable choice of parameters the…
In this contribution we compute some nonleptonic and semileptonic decay widths of $B_s$ mesons, working in the context of constituent quark models \cite{Albertus:2014gba, Albertus:2014bfa}. For the case of semileptonic decays we consider…
Recent measurements of branching fractions, form factors and decay constants of leptonic and semileptonic decays of D_(s)-mesons acquired at experiments running at the Upsilon(4S) resonance energy are reviewed.
We study the loop induced rare decays $B_s(B_d)\to\gamma\nu\bar\nu$ within the standard model. Both constituent quark model and pole model are used and the branching ratios turn out to be of the orders of $10^{-8}$ for $B_s\to \gamma \nu…