相关论文: $b \to s l \bar l $ in the minimal supergravity mo…
The contribution to the decay $b\to s \gamma$ in the Minimal Supersymmetric Standard Model with radiative electroweak breaking is presented. The impact of a detection of this inclusive decay at the SM level is discussed. Results for other…
The rare decays $B_{s(d)} \to \mu^+\mu^-$ play a key role for the testing of the Standard Model. An overview of the most recent theoretical predictions of the corresponding branching ratios is given, emphasizing that the sizable decay width…
Motivated by the recent observation of lepton universality violation in the flavour changing charged current transitions $b \to c l \bar{\nu}_l$, we intend to scrutinize the lepton non-universality effects in rare semileptonic $B$ meson…
We consider the most general new physics effective Lagrangian for b--> s l+ l-. We derive the upper limit on the branching ratio for the processes B_s--> l^+ l- where l=e, mu, subject to the current experimental bounds on related processes,…
Taking into account the constraints imposed by experimental data on the parameter space, we analyze the lepton flavor violating decays of B meson in the scenario of the minimal R-symmetric supersymmetric standard model. The prediction of…
We study both the branching ratio for $b \to s \gamma$ decay and the muon anomalous magnetic moment, $a_{\mu} \equiv (g-2)_{\mu} /2$, in the minimal supersymmetric standard model with gauge-mediated supersymmetry breaking. Combining new…
Rare decays mediated by $b \to s \nu \bar \nu$ transitions have been reported by the Belle II experiment. The branching ratio of the decay $B^+ \to K^+ \nu \bar \nu$ is found to be enhanced with respect to the standard model value. If taken…
The complete calculation of the lowest order short-distance contributions to the $B_{s}\to\gamma\gamma$ decay in the SM are presented. The amplitude and branching ratio are calculated.
The exclusive $B_s -> \gamma l^+ l^- $ decay is analyzed in the framework of a family nonuniversal Z' model by calculating the differential branching ratio, double lepton polarizations and forward-backward asymmetries. Our results are…
We begin to analyze and contrast the predictions for the decay $b\to s\ell^+\ell^-$ in the Left-Right Symmetric Model(LRM) with those of the Standard Model(SM). In particular, we show that the forward-backward asymmetry of the lepton…
Deviations from the standard model prediction have been observed in several leptonic and semileptonic $B$ meson decays to $\tau\nu$ final states mediated via $b \to u$ and $b \to c$ charged current interactions. The measured value of ratio…
We consider the effect of new physics interactions in the form of tensor operators on the branching ratio of B_s --> l+ l- gamma where l=e, mu. We find that the present data on the inclusive branching ratio B --> X_s l+ l- puts a strong…
We study B_s --> mu+ mu- in the context of the R-parity violating minimal supergravity in the high tan beta regime. We find that the lowest value of the branching ratio can go well below the present LHCb sensitivity and hence B_s --> mu+…
After a brief review of the inclusive and exclusive rare semileptonic decays of B mesons in the standard model (SM), an overview of recent theoretical developments in this field is given. New physics effects on various observables such as…
We consider the most general new physics effective Lagrangian for b --> s l+ l-. We derive the upper limit on the branching ratio for the processes B_s --> l+ l- where l=e, mu, subject to the current experimental bounds on related…
We consider the effect of new physics on the branching ratio of B_s--> l+ l- gamma where l=e,mu. If the new physics is of the form scalar/pseudoscalar, then it makes no contribution to B_s--> l+ l- gamma, unlike in the case of B_s--> l+ l-,…
We investigate $ B_s^0\rightarrow l^+ l^-\gamma $ decays in a nonuniversal Z' model derived from extension of the standard model (SM). Considering the Z'-mediated flavor changing neutral current (FCNC) effects we calculate the branching…
In recent times, several hints of lepton non-universality have been observed in semileptonic $B$ meson decays, both in the charged-current ($b \to c l \bar \nu_l$) and neutral-current ($b \to s ll $) transitions. Motivated by these…
In the context of the littlest Higgs(LH) model, we study the contributions of the new particles to the branching ratio $R_{b}$. We find that the contributions mainly dependent on the free parameters $f$, $c'$ and $x_{L}$. The precision…
We calculate the inclusive branching ratio for B--> X_s gamma, the inclusive branching ratios and asymmetries for B--> X_s l+ l- and the anomalous magnetic moment g-2 of the muon, within a minimal gauge-mediated SUSY-breaking model which…