Related papers: Notes on $B\to K^* \gamma$
The exclusive decay modes $B \to K \gamma\gamma$ and $B_s \to \eta (\eta') \gamma\gamma$ are shown to have significant branching ratios of approximately $0.5\times 10^{-7}$. This first calculation of these modes employs a model based on a…
In the paper, we conduct a detailed investigation of the rare decay processes of charged meson, specifically $B^+ \to K^+\ell^+\ell^-$ with $\ell=(e,\mu,\tau)$ and $B^+ \to K^+\nu\bar{\nu}$. These processes involve…
We extend the Standard Model (SM) analysis of Ref. [1], which was limited to light leptons in the final state, to the semileptonic $B \to D^* \tau \nu_\tau$ decay. By using quantities that can be analised without the knowledge of $\vert…
A simple relativistic model of heavy-light mesons is applied to the rare decay B -> K* gamma in the standard model. We find Gamma(B -> K* gamma)/Gamma(b -> s gamma)=(17 \pm 4)% and BR(B -> K* gamma)=(4.8 \pm 1.9) \times 10^{-5}(V_cb/.04)^2.…
The form factors of the semileptonic $B\to \pi\pi\ell\bar\nu$ decay are calculated from QCD light-cone sum rules with the distribution amplitudes of dipion states. This method is valid in the kinematical region, where the hadronic dipion…
We present an improved calculation of $B\to$ light pseudoscalar formfactors from light-cone sum rules, including one-loop radiative corrections to twist-2 and twist-3 contributions, and leading order twist-4 corrections. The total…
We update the lattice calculation of the $B\to\pi$ semileptonic form factors, which have important applications to the CKM matrix element $|V_{ub}|$ and the $B\to\pi\ell^+\ell^-$ rare decay. We use MILC asqtad ensembles with $N_f=2+1$ sea…
Theoretical predictions for the branching ratios of the $B \rightarrow X_s\,\gamma$ and $B \rightarrow K^*\,\gamma$ decays are calculated in the Standard Model and in the (type II) two-Higgs-doublet model. Both the complete leading and the…
We develop a new method in lattice QCD to calculate the form factor F(1) at zero recoil. This is the main theoretical ingredient needed to determine |V(cb)| from the exclusive decay anti-B --> D* lepton anti-neutrino. We introduce three…
We present our study on $B \to \pi l \nu$ semileptonic decay form factors with NRQCD action for heavy quark from a quenched lattice QCD simulation at $\beta$=5.9 on a $16^3\times 48$ lattice. We obtain form factors defined in the context of…
Taking into account the $\Lambda$ baryon distribution amplitudes and the most general form of the interpolating current of the $\Lambda_{b}$, the semileptonic $\Lambda_{b}\rar \Lambda \ell^+\ell^- $ transition is investigated in the…
We carry out an analysis of the full set of ten $\bar{B}\to D^{(*)}$ form factors within the framework of the Heavy-Quark Expansion (HQE) to order $\mathcal{O}(\alpha_s,\,1/m_b,\,1/m_c^2)$, both with and without the use of experimental…
We use QCD sum-rules to study the decays $\phi \to \eta \gamma$ and $\phi \to \eta^\prime \gamma$, obtaining ${\cal B}(\phi \to \eta \gamma)=(1.15 \pm 0.2) 10^{-2}$ and ${\cal B}(\phi \to \eta^\prime \gamma)=(1.18 \pm 0.4) 10^{-4}$, in very…
We report on a recent computation of the form factors in semi-leptonic decays of the $\mathrm{B}_\mathrm{s}$ using Heavy Quark Effective Theory (HQET) formalism applied on the lattice. The connection of the form factors with the 2-point and…
We present a new and very high statistics study of D and D_s semileptonic decay form factors on the lattice. We work with MILC N_f=2+1 lattices and use the Highly Improved Staggered Action (HISQ) for both the charm and the light valence…
The method of calculating electroweak decay matrix elements between heavy-heavy and heavy-light meson states is developed in the framework of relativistic quark model based on the quasipotential approach in quantum field theory. This method…
Lattice Monte Carlo simulations now include the effects of 2 light sea quarks and 1 strange sea quark through the use of an improved staggered fermion action. Consequently, results important to phenomenology are free of the approximate 10%…
We calculate the branching ratios of the hadronic \Lambda_b decays to \eta and \eta^\prime in the factorization approximation where the form factors are estimated via QCD sum rules and the pole model. Our results indicate that, contrary to…
We compute NNLO (${\cal O}(\alpha_s^2)$) corrections to the hard-scattering kernels entering the QCD factorization formula for $B\to V\gamma$ decays, where $V$ is a light vector meson. We give complete NNLO results for the dipole operators…
In this letter we revisit the Standard Model predictions for $\mathcal{B}(B\to K^{(\ast)}\nu\bar{\nu})$ and discuss the opportunities that open up when combining its partial decay rate with that of $B\to K^{(\ast)}\ell\ell$. In the Standard…