Related papers: Rare radiative charm decays within the standard mo…
A relativistic quark model is extended to incorporate chiral and gauge symmetries. We obtain the DD*pi and DD*gamma couplings and find that the ratio Gamma(D*0->D0pi0)/Gamma(D*0->D0gamma) constrains the charm-quark mass close to 1.45 GeV.…
A brief overview of the recent measurements of the branching ratio of the rare $K_L^0 \to \mu^+ \mu^-$ decay in the context of their agreement with the Standard Model (SM) is given. It is shown that KEK result well correlates with the SM…
In this paper, I study the branching ratio of the rare radiative decay $B_s \to \nu \bar{\nu} \gamma$ in the framework of the Fourth-Generation Standard Model and the Two-Higgs-Doublet Model. It is shown that this quantity is a very…
We calculate the branching ratios for B_{d}^{0}->(b_{1},h_{1})gamma at next-to-leading order (NLO) of alpha_{s} where b_{1} and h_{1} are the corresponding radially excited axial vector mesons of rho and omega respectively. Using the…
Recent results from Belle and BaBar Collaborations hint at a small $\sin2\phi_1$, while the measured $B\to\pi\pi$ rate also seems to be on the low side. Supersymmetric (SUSY) models with down squark mixings can account for the deficits in…
Recent experimental progress on baryonic rare decays has spurred a deeper investigation on flavor-changing neutral current transitions in the baryon sector. Within the framework of QCD sum rules, we derive a complete set of form factors for…
The recent Tevatron result on the top quark forward-backward asymmetry, which deviates from its standard model prediction by 3.4$\sigma$, has prompted many authors to build new models to account for this anomaly. Among the various…
In this talk an analysis of the rare exclusive $B$ decays $B\to K\nu\bar\nu$ and $B\to K^{*}\nu\bar\nu$ within and beyond the Standard Model is presented. Combining new form factor determinations from lattice QCD with light-cone sum rule…
A status report on the theory of radiative rare $B$ decays in the standard model is presented, with focus on inclusive decays $B \rightarrow X_{(s,d)}\, \gamma$ and exclusive decays $B \rightarrow (K^\ast,\omega,\rho) \, \gamma$. CP…
The decays K_{L,S} -> \pi^o \pi^o \nu \bar{\nu} and K_{L,S} -> \pi^+ \pi^- \nu \bar{\nu} involve the weak transition from a strange to a non-strange quark. Although they have considerably smaller branching ratios than those for the…
In this note, we calculate the branching ratio and CP asymmetry parameters of $B_s\to\pi\rho$ in the framework of perturbative QCD approach based on $k_T$ factorization. This decay can occur only via annihilation diagrams in the Standard…
We perform the first global fit of rare charm transitions using recent data on $D^0\to \mu^+\mu^-$, $D^+\to\pi^+\mu^+\mu^-$, $\Lambda_c\to p\mu^+\mu^-$ and $D^0\to\pi^+\pi^-\mu^+\mu^-$ decays, including angular observables. We work out…
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…
Existing predictions for the branching ratio for $\phi\rightarrow K\bar{K}\gamma$ {\it via} $\phi\rightarrow S\gamma$ (where $S$ denotes one of the scalar mesons $f_0$(975) and $a_0$(980)) vary by several orders of magnitude. Given the…
We study the nine possible rare charm meson decays D->Pl^+l^- (P=pi,K,eta,eta') using the Heavy Meson Chiral Lagrangians and find them to be dominated by the long distance contributions. The decay D^+ -> pi^+l^+l^- with the branching ratio…
We perform a comprehensive study of a number of rare charm decays, incorporating the first evaluation of the QCD corrections to the short distance contributions, as well as examining the long range effects. For processes mediated by the…
We consider the branching ratio for the process $t \to c \gamma$ in the context of the General Two Higgs Doublet Model type III. We find that taking into account reasonable values for the parameter $\tan \beta$ is possible to get values of…
Exclusive weak radiative B meson decays are studied using the covariant oscillator quark model. The branching ratios for the processes B0 to K*0 gamma and B to K* gamma have been estimated. These are in reasonable agreement with the…
We investigate the exclusive rare semileptonic decays: $B(B_c)\to K(D_{(s)})l\bar{l}/\Sigma\nu_l\bar{\nu_l}$ ($l=\mu, \tau$) in the framework of relativistic independent quark (RIQ) model based on an average flavor independent confining…
The branching ratio and direct CP asymmetry of the decay mode $B_s \to \phi \pi^0$ have been calculated within the QCD factorization approach in both the standard model (SM) and the non-universal $Z^\prime$ model. In the standard model, the…