Related papers: Rare radiative leptonic B-decays
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…
In this paper, we calculate the top quark rare decay t-ch in a supersymmetric extension of the standard model where baryon and lepton numbers are local gauge symmetries. Adopting reasonable assumptions on the parameter space, we find that…
We study the effect of scalar leptoquarks on the exclusive rare $B$ meson decays $\bar{B}_d^0 \rightarrow \bar{K}^{* 0}\left(\rightarrow K^-\pi^+\right) l^+ l^-$ in the full kinematically accessible physical region. We work out the…
We report the first observation of the radiative hyperonic B decay B+ -> p Lambdabar gamma, using a 140 fb^{-1} data sample recorded on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider. The…
We studied radiative B meson decays with the Belle detector. We measured the following branching fractions; Br(B->K*0(892)\gamma) = (49.6 \pm 6.7 \pm 4.5) x 10^{-6}, Br(B->K*+(892)\gamma) = (38.9 \pm 9.3 \pm 4.1) x 10^{-6}, Br(B->Xs\gamma)…
In this work, we use the QCD sum rule method to study the radiative decays of the vector and axial-vector $B_c$ mesons to each of three charmed strange mesons, $D_s$, $D^*_s$ and $D_{s1}$, through their dominant weak annihilation channels.…
We have searched for the leptonic and radiative leptonic B decays, B^+ -> mu^+ nu, B^+ -> e^+ nu gamma and B^+ -> mu^+ nu gamma. Using a 140 fb^{-1} data sample collected with the Belle detector at the KEKB asymmetric e^+ e^- collider, we…
In this work, we perform a lattice QCD calculation of the branching ratios and the form factors of radiative leptonic decays $P \to \ell \nu_\ell \gamma$ ($P = \pi, K$) using $N_f=2+1$ domain wall fermion ensembles generated by the RBC and…
The spectra and form factors of exclusive semi-leptonic decays of B-meson are analyzed, taking account of confined effects of quarks by the Covariant Oscillator Quark Model. The predicted B --> (D*,D)l nubar_l spectra with the conventional…
We discuss some selected topics in rare B decays in the context of the standard model and compare theoretical estimates with available data. Salient features of the perturbative-QCD and power corrections in the decay rate for $B \to X_s +…
We calculate the branching ratio of $\Lambda_b \to \Lambda \gamma$ in the standard model using the PQCD method. The predicted branching ratio $B(\Lambda_b \to \Lambda \gamma)$ is about $(4.3\sim 8.6)\times 10^{-8}$, with reasonable…
The recent CLEO results on on radiative $b$-quark decays are used to derive constraints on anomalous $WW\gamma$ couplings. These constraints are compared with expectations from $p\bar p\rightarrow e^\pm p\llap/_T\gamma+X$ at the Tevatron.…
We show how radiative QCD corrections calculated in terms of quarks can be incorporated at the hadron level in inclusive semileptonic B-meson decays. The bound state effects are described by a momentum distribution function of the $b$…
We present a systematic analysis for the rare baryonic exclusive decays of $\Lambda_b\to\Lambda l^+ l^- (l=e,\mu,\tau)$. We study the differential decay rates and the di-lepton forward-backward, lepton polarization and various CP…
We report our theoretical calculations on the branching fractions for the semileptonic $B$ and $B_s$ decays, i.e., $B (B_s) \to (P,\, V,\, S,\,A) \ell \nu_\ell$, where $P$ and $V$ denote the pseudoscalar and vector mesons, respectively,…
A symmetry-preserving approach to the continuum bound-state problem in quantum field theory is used to calculate the masses, leptonic decay constants and light-front distribution amplitudes of empirically accessible heavy-light mesons. The…
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 semileptonic decay of a b-quark, b--> c l nu, is considered in the relativistic limit where the decay products are approximately collinear. Analytic results for the double differential lepton energy distributions are given for finite…
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…
We calculate nonperturbative ${\cal O}(\Lambda^2_{QCD}/m^2_c)$ corrections to the dilepton invariant mass spectrum and the forward-backward charge asymmetry in $B\to X_se^+e^-$ decay using a heavy quark expansion approach. The method has…