相关论文: Determining V(ub) from B+ --> D*+(s) e+ e- and B+ …

Heavy Quark Expansions for semileptonic decays of beauty hadrons are briefly reviewed. I analyze how $|V(cb)|$ can be extracted from the semileptonic width of $B$ mesons, the average semileptonic width of all weakly decaying beauty hadrons…

We have observed a signal for the decay D*+ -> D+ gamma at a significance of 4 standard deviations. From the measured branching ratio B(D*+ -> D+ gamma)/B(D*+ -> D+ pi0)=0.055 +- 0.014 +- 0.010 we find B(D*+ -> D+ gamma)= 0.017 +- 0.004 +-…

We study the (tree-level) weak radiative decays of $B$ mesons. We present a numerical estimate for the inclusive $b \to X_c \gamma (\gamma)$ modes based on the free-quark decay. We then review what is known for the $B \to D^\star \gamma$…

Searches are presented for $B_{c}^{+} \to D h^+ h^-$ decays, where $D$ is a charmed meson and $h^{\pm}$ is a charged pion or kaon, using $pp$ collision data collected by the LHCb experiment corresponding to an integrated luminosity of…

The form factors of the rare $\Lambda_b\to n l^+l^-$ decays are calculated in the framework of the relativistic quark-diquark picture of baryons with the consistent account of the relativistic effects. Their momentum transfer squared…

The D^+ --> omega + pi^+ decay is studied by decomposing its amplitude into a sum of factorizable and non-factorizable ones. Its rate is predicted as a function of mass and width of a hypothetical hybrid meson.

We calculate the main observables in $B_{u,d}\to (\rho,\omega,K^*)\gamma$ and $B_s\to (\bar K^*,\phi)\gamma$ decays, i.e. branching ratios and CP and isospin asymmetries. We include QCD factorisation results and also the dominant…

We show that the CP phase \gamma can be obtained from measurements of Bd(t) -> D(*)+ D(*)- and Bd -> Ds(*)+ D(*)-. These decays are related by flavor SU(3) in the limit where spectator-quark contributions are small. If the…

The radiative decays $ B^{*} (D^{*})\rightarrow B(D) \gamma$ are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson…

We perform the simultaneous $|V_{ub}|$ and $|V_{cb}|$ extractions with only the exclusive $\Lambda_b$ decays of $\Lambda_b\to (p,\Lambda_c^+)\mu\bar \nu_\mu$, $\Lambda_b\to p\pi^-$ and $\Lambda_b\to \Lambda_c^+ (\pi^-, D^-)$. We obtain that…

The use of inclusive B decays to determine |V_{ub}|, |V_{cb}|, m_b and heavy quark matrix elements via spectral moments is discussed.

In the ratio of ratios of rates for radiative and semileptonic decays of B and D to K* and rho mesons the non-computable form factors mostly cancel out. The resulting method for the determination of Vub is largely free of hadronic…

We study the novel decays $B^{*}\to B\gamma\gamma $ and $D^{*}\to D\gamma \gamma $ using the framework of the Heavy Meson Chiral Lagrangian (HM$\chi$L) to leading order in chiral perturbation theory. The branching ratios of these decays are…

A data set corresponding to an integrated luminosity of $9 \text{fb}^{-1}$ of proton-proton collisions collected by the LHCb experiment has been analysed to search for $B_c^+ \to D^{(*)+}_{(s)} \overset{\scriptstyle (-)}{D}{}^{(*)0}$…

Using the most general, model independent form of the effective Hamiltonian rare decays (B -> l^+ l^- gamma (l=mu, tau)) are studied. The sensitivity of the photon energy distribution and branching ratio to the new Wilson coefficients is…

In our previous paper we applied U-spin symmetry to charmless hadronic B+- --> M0 M+- decays for the purpose of precise extraction of the unitarity angle gamma. In this paper we extend our approach to neutral B0 and Bs --> M1 M2 decays. A…

We present a closed form expression for |V_{ub}|^2/ |V_{tb} V_{ts}^*|^2 in terms of the endpoint photon and lepton spectra from the inclusive decays B -> X_s\gamma and B -> X_u\ell\nu, respectively, which includes the resummation of the…

We reemphasize the strong dependence of the branching ratios $B(K^+\to\pi^+\nu\bar\nu)$ and $B(K_L\to\pi^0\nu\bar\nu)$ on $|V_{cb}|$ that is stronger than in rare $B$ decays, in particular for $K_L\to\pi^0\nu\bar\nu$. Thereby the persistent…

Using the previous Belle measurement of the inclusive photon energy in $B\to X_s\gamma$ decays, we determine the first and second moments of this spectrum for minimum photon energies in the $B$ meson rest frame ranging from 1.8 to 2.3 GeV.…

In rare $B$ meson decays $B\rightarrow K \ell^+ \ell^-$, a possible contribution of $\ell^+\ell^-$ emission via photon from the "spectator" quark $q$ ($q=u,d$) in the $B$ meson $(q\bar{b})$ is investigated in addition to the conventional…