相关论文: A study on the rare radiative decay $B_c \to D_s^*…
We investigate the radiative $B_{c} \to D_{s1} \gamma$ transition in the framework of QCD sum rules. In particular, we calculate the transition form factors responsible for this decay in both weak annihilation and electromagnetic penguin…
In this paper, we study the rare radiative processes $B_c\to D_{sJ} ^{(*)}\gamma$ within the Standard Model, where $D_{sJ}^{(*)}$ stands for the meson $D_s^*$,~$D_{s1}(2460,2536)$ or ~$D_{s2}^*(2573)$. During the investigations, we consider…
Weak radiative baryonic B decays $B\to\B_1\ov \B_2\gamma$ mediated by the electromagnetic penguin process $b\to s\gamma$ have appreciable rates larger than their two-body counterparts $B\to\B_1\ov \B_2$. The branching ratios for…
Applying the perturbative QCD ( PQCD ) method, we study the decay $B_c\rightarrow D_s^*\gamma$ in the standard model and multiscale walking technicolor model. In the SM, we find that the contribution of weak annihilation is more important…
The short-distance contribution due to the $c\to u\gamma$ penguin as well as long-distance contributions are considered in an analysis of $D\to V\gamma$ decays, the latter being dominant. The matrix elements for nine $D\to V\gamma$…
We obtain predictions for a number of radiative decays $B_{(s)}\to V\gamma$, $V$ the vector meson, which proceed through the weak-annihilation mechanism. Within the factorization approximation, we take into account the photon emission from…
We give predictions for the branching ratios of several rare radiative B-decays which proceed only through weak annihilation mechanism. In addition to previous analysis we estimate the branching ratios of $\bar{B}^0_s\to D^{*0}\gamma$ and…
Rare loop-induced decays are sensitive to New Physics in many Standard Model extensions. In this paper we discuss the potential of the LHCb experiment to very rare $\mathrm{B_s} \to \mu^+ \mu^-$ decays, radiative penguin $\mathrm{b \to…
The ampitude of the $B\to\rho\gamma$ decay induced by the flavour-changing neutral currents contains the penguin contribution and the weak-annihilation contribution generated by the 4-quark operators in the effective Hamiltonian. The…
In this talk, we present the predictions for a number of radiative decays $B_{(s)}\to V\gamma$, with the vector meson in the final state, which proceed through the weak-annihilation mechanism. Within the factorization approximation, we take…
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…
An overview of exclusive two-body and three-body baryonic B decays is given. The threshold enhancement effect in the dibaryon invariant mass and the angular distributions in the dibaryon rest frame are stressed and explained. Weak radiative…
Motivated by the observation of the decay $\bar{B}\to \bar{K}^*\gamma$ by CLEO, we have systematically analyzed the two-body weak radiative decays of bottom and charmed hadrons. There exist two types of weak radiative decays: One proceeds…
We provide Standard Model expectations for the rare radiative decays B->K^* gamma, B->rho gamma and B-> omega gamma, and the electroweak penguin decays B->K^* l^+ l^- and B->rho l^+ l^- at the next-to-leading order (NLO), extending our…
We compute for the first time the long-distance penguin contribution to the double radiative $B$-meson decays due to the purely hadronic operators acting with the electromagnetic current in the background soft-gluon field from first…
The three-body decay $B^0(B_s)\to \gamma\nu \bar{\nu}$ can occur via penguin and box diagrams in the standard model (SM). These channels are useful to determine the decay constants $f_B$ ($f_{B_s}$) and $B$ ($B_s$) meson wave function.…
Motivated by the observation of the decay B to K* gamma by the CLEO collaboration, we have systematically analyzed the weak radiative decay Lambda_b to Lambda gamma, evaluating the confined effects of quarks in the covariant oscillator…
We report on recent progress on perturbative QCD calculations of certain exclusive rare weak $B$ meson decays involving hard photons. In the limit of a photon energy $E_\gamma$ much larger than $\Lambda_{QCD}$, the amplitudes for such…
Weak radiative baryonic B decays $\bar B\to B_1\bar B_2\gamma$ mediated by the electromagnetic penguin process $b\to s\gamma$ are re-examined within the framework of the pole model. The meson pole contribution that has been neglected before…
Radiative penguin decays provide an indirect probe for physics beyond the Standard Model and contribute to the determination of the CKM matrix elements. Copious quantities of B mesons produced at the B-Factories permit precision…