Related papers: The $B_c$ decay rate in the Standard Model
The mass spectrum of $c \bar b$ meson is investigated with an effective quark-antiquark potential of the form $\frac{-\alpha_c}{r}$ + $A r^{\nu}$ with $\nu$ varying from 0.5 to 2.0. The S and P-wave masses, pseudoscalar decay constant, weak…
Many topics are discussed in b physics including lifetimes, decay mechanisms, determinations of the CKM matrix elements |V_{cb}| and |V_{ub}|, facilities for b quark studies, neutral $B$ meson mixing, rare b decays, hadronic decays and CP…
We have calculated the decay rates of the $B_s$ meson in a number of exclusive two--body decay channels using the Bauer--Stech--Wirbel model for current matrix elements. The influence of the free parameters of the model on the predictions…
In this work we tried to predict the parameters of $B^{*}_c$ meson. Simple assumptions gave us following parametres $m_{B_{c}^{*}}=6329\pm 10$ MeV and $f_{B_{c}^{*}}= 535.5\pm57.8$ MeV (for $\Lambda_{B_{c}^{*}}=2.26\pm 0.14$ GeV in…
Phenomenological models of heavy flavour decays differ significantly in their predictions of global features of $B_c$ decays, like the $B_c$ lifetime or the relative weight of $c\ra s$ and $b\ra c$ transitions. The $1/m_Q$ expansion which…
We present the first lattice QCD calculation of the decay constants f_B and f_{B_s} with physical light quark masses. We use configurations generated by the MILC collaboration including the effect of u, d, s and c HISQ sea quarks at three…
A status report on the theory and phenomenology of rare radiative $B$ decays in the standard model is presented with emphasis on the measured decays $B \to X_s \gamma$ and $B \to K^* \gamma$. Standard model is in agreement with experiments…
I review the current status of measurements involving semi-tauonic $B$ meson decay at the $B$-factories. I briefly discuss the experimental methods and highlight the importance of background contributions especially from poorly understood…
We calculate the semileptonic branching ratio and the charm counting of inclusive $B$ meson decays using the perturbative QCD formalism. For the nonleptonic decays, we employ the modified factorization theorem, in which Wilson coefficients…
We investigate the decays $B_c^- \rightarrow D_{s}^{(*)-}\ell^+\ell^-$ and $B_c^- \rightarrow D_{s}^{(*)-}\nu\bar{\nu}$ within the Standard Model (SM), employing perturbative QCD form factors that are sensitive to the wave functions of…
A number of recent experimental measurements suggest the possibility of a breakdown of lepton ($\ell$) universality in exclusive $b \to c \ell \nu_\ell$ semileptonic meson decays. We analyze the full differential decay rates for several…
For purely leptonic decays of pseudoscalar mesons, the decay rates are related to the product of the relevant weak interaction-based CKM matrix element of the constituent quarks on the one hand, and the strong interaction parameter, the…
We investigate a new constraint on new-physics interpretations of the anomalies observed in $B\to D^{(*)}\tau\nu$ decays making use of the lifetime of the $B_c^-$ meson. A constraint is obtained by demanding that the rate for…
I review the status of the rare decays B_s --> mu+mu- and B_d --> mu+mu-. The latest Standard Model predictions for the corresponding branching ratios are discussed. An overview of additional observables that are accessible in the B_s -->…
The decay constants of the low lying S-wave $B_c$ mesons, i.e. $B_c(nS)$ and $B^*_c(nS)$ with $n\leq 3$, are calculated in the nonrelativistic quark model. The running coupling of the strong interaction is taken into account, and the…
Heavy quark decays provide a very advantageous investigation to test the Standard Model (SM). Recently, promising experiments with \textit{b} quark, as well as the analysis of the huge data sets produced at the B factories, have led to an…
I report on developments in the experimental and phenomenological understanding of the rare decays of mesons containing b and c quarks, especially as they pertain to the understanding of the CKM matrix and the testing of the standard model.…
We study $B_c \to (D,\,D^{\ast})\,l\,\nu$ semileptonic decays mediated via $b \to u\,l\,\nu$ charged current interactions using the $B_c \to (D,\,D^{\ast})$ transition form factors obtained in the covariant light front quark model. We give…
Using our analytical expressions that well model the lattice simulations of the gluonic excitations, we use the extended quark potential model to study the effects of orbital and radial excitations on the masses and sizes of conventional…
We review the status of the Standard Model theory of neutron beta decay. Particular emphasis is put on the recent developments in the electroweak radiative corrections. Given that some existing approaches give slightly different results, we…