相关论文: Radiative B_c -> tau nu_tau gamma decay
The radiative B -> tau^+ tau^- gamma decay is investigated in the framework of the Standard Model. When only short (short and long together) distance contributions are taken into account, the Branching Ratio is found as 9.54x10^(-9)…
The radiative B ->\tau^+ \tau^- \gamma decay is investigated in the framework of the two Higgs doublet model . The dependence of the differential branching ratio on the photon energy and the branching ratio on the two Higgs doublet model…
The radiative leptonic $B_{c}\to\tau\bar{\nu_{\tau}}\gamma$ decay is analysed in context of 2HDM. It is shown that with large values of $tan\beta$, the contributions of Model II to the decay rate exceeds considerably the Standard Model…
To the leading order, the radiative leptonic decays $B_c \to \gamma \ell \bar \nu$ ($ \ell=e, \mu$) are studied carefully. In the study, a non-relativistic constituent quark model and the effective Lagrangian for the heavy flavour decays…
The radiative B_c -> l nu gamma decay is investigated in the Standard Model in framework of the light cone QCD. The transition form factors and decay width are calculated. A comparison of light cone QCD and constituent quark model…
Using 4.68 fb^{-1} of e^+e^- annihilation data collected with the CLEO II detector we have studied tau radiative decays tau --> mu nu nu gamma and tau --> e nu nu gamma. For a 10 MeV minimum photon energy in the tau rest frame, the…
Using 4.68 fb^{-1} of e^+e^- annihilation data collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) we have studied tau radiative decays tau -> mu nu nu gamma and tau -> e nu nu gamma. For a 10 MeV minimum photon…
We present the differential rates and branching ratios of the radiative decays $\tau \to l \bar{\nu} \nu \gamma$, with $l=e$ or $\mu$, and $\mu \to e \bar{\nu} \nu \gamma$ in the Standard Model at next-to-leading order. Radiative…
In this work, the radiative Bc -> D*_s gamma decay is investigated in the framework of QCD sum rules. The transition form factors responsible for the decay are calculated. The branching ratio for this decay is estimated to be order of 10^-5…
The experimental results of the \babar\ and Belle collaborations are presented on the measurement of the branching ratio for the decay $B^\pm \to \tau^\pm \nu$, and the limits set on the branching ratios for the decays $B^\pm \to e^\pm \nu,…
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 recent discovery of the B_c meson by the CDF collaboration and proposed new experiments at Fermilab and CERN motivate new theoretical studies of the B_c system. Here we investigate the radiative leptonic decay B_c -> gamma l nu. This…
B_s-meson double radiative decay $B \to \gamma\gamma$ is investigated in frame of supersymmetric extension of the standard model. The branching ratio is calculated. It is shown that for light Higgs particle and heigh $\tan\beta$…
An informal review is given of the status and direction of experiments on radiative B decays -- b -> s gamma and b -> d gamma. Branching fractions for exclusive and inclusive b -> s gamma decays, CP asymmetry limits, the photon energy…
We study the rare radiative dileptonic decays $B^0(B_s)\to \gamma\ell^+\ell^-$ ($\ell=e,\mu$) in the standard model. By using the $B$ meson wave function constrained by non-leptonic decays, the branching ratios turn out to be of the order…
We have studied the one meson radiative tau decays: tau- -> nu(tau) pi-(K-) gamma, computing the structure dependent contributions within a Lagrangian approach based on the large-N(C) limit of QCD that ensures the proper low-energy limit…
In this article, we calculate the $B_c^* \to B_c$ electromagnetic form-factor with the three-point QCD sum rules, then study the radiative decays $ B_c^{*\pm} \to B_c^{\pm} \gamma$. Experimentally, we can study the radiative transitions…
Recent results in radiative B decays from the Belle and BaBar collaborations are discussed. New measurements of the decay rate and CP asymmetries in b -> s gamma and b -> d gamma decays are presented, together with measurements of the…
We perform a measurement of the branching fractions for tau -> l gamma nu anti-nu (l= e, mu) decays for a minimum photon energy of 10 MeV in the tau rest frame using 430 fb^-1 of e^+ e^- collisions collected at the center-of-mass energy of…
Within the light front framework, we calculate the form factors for $B\to\gamma$ transitions directly in the entire physical range of momentum transfer. Using these form factors, we study the radiative decays of $B\to l\nu_l\gamma$ and…