相关论文: Why is the B -> eta' X decay width so large ?

We report measurements of radiative B decays with K eta gamma final states, using a data sample of 253 /fb recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- storage ring. We observe B+ -> K+ eta gamma for the…

The $\eta'$ which is an $SU(3)_F$ singlet state can contain a pure gluon component, gluonium. We examine this possibility by analysing all available experimental data. It is pointed out that the $\eta'$ gluonic component may be as large as…

We have measured the branching fraction of the inclusive radiative B meson decay B --> X(s) gamma to be Br(B->X(s)gamma)=(3.36 +/- 0.53(stat) +/- 0.42(sys) +0.50-0.54(th)) x 10^{-4}. The result is based on a sample of 6.07 x 10^6 BBbar…

We study the inclusive charmless semileptonic decay of $\Lambda_b$, $\Lambda_b \to X_u l \nu_l$, in the framework of heavy quark expansion and find that the rate is substantially enhanced by spectator effect. We obtain $Br(b \to X_u l…

Motivated by recent results on charmed baryons from CLEO and FOCUS, we reexamine the couplings of the orbitally excited charmed baryons. Due to its proximity to the [Sigma_c pi] threshold, the strong decays of the Lambda_c(2593) are…

Some recent theoretical work on inclusive B decays relevant for the model independent determination of |V_{ub}| and |V_{cb}| is summarized. The theoretical predictions and their reliability for several differential decay distributions in B…

The dipionic transition of the $X(3872)$ to the $\eta_c$ was investigated using an effective Lagrangian approach. In this study, the $X(3872)$ was assumed to be a $D\bar{D}^\ast + \text{c.c.}$ bound state with the quantum numbers…

The increasing number of flavour anomalies motivates the investigation of new processes where tensions similar to the observed ones may emerge. It is necessary to identify observables sensitive to physics beyond the Standard Model. The…

Decay rates of the B-meson are studied through charmless and strangless transitions into pi, rho, omega and gamma systems. The important features of these modes are their clean signatures. The CLEO II collaboration has recently reported the…

In this work we summarize the current status of measured exclusive semileptonic branching fractions containing charm mesons. We use the available experimental data to evaluate the difference between the sum of exclusive measurements and the…

Phenomenological models of heavy flavour decays differ significantly in their predictions of global features of $B_c$ decays, like the $B_c$ lifetime or the relative weight of $c\ra s$ and $b\ra c$ transitions. The $1/m_Q$ expansion which…

Using soft-collinear effective theory we describe at leading order in 1/m_b all the semi-inclusive hadronic B -> XM decays near the endpoint, where an energetic light meson M recoils against an inclusive jet X. We also include the decays…

We study semileptonic B decay to the exclusive charmless states pi, rho/omega, eta and eta' using the 16 fb-1 CLEO Upsilon(4S) data sample. We find B(B^0 -> pi^-l^+nu) = (1.37 +- 0.15_stat +- 0.11_sys) x 10^-4 and B(B^0 -> rho^- l^+ nu) =…

We discuss the role of so-called "intrinsic-charm" operators in semi-leptonic B-meson decays, which appear first at order 1/m_b^3 in the heavy quark expansion. We show by explicit calculation that -- at scales mu <= m_c -- the contributions…

A calculation of the leading isospin-breaking contributions to the B -> K^* gamma decay amplitudes based on the QCD factorization approach is presented. They arise at order Lambda/m_b in the heavy-quark expansion and are due to annihilation…

We investigate whether known properties of the $\eta'$ meson are consistent with its being the Goldstone boson of the spontaneously broken anomaly-free R symmetry required in the light gluino scenario. We fit the masses and $2\gamma$ decays…

With ~10fb$^{-1}$ data from Belle, the results of b to c and u decays have been represented here. Several decay modes have been studied, which include charmonium, semileptonic decay and Cabibbo-suppressed decays mode. The preliminary…

We identify two Cabibbo suppressed $D^+$ decay modes with anomalously high branching ratios which are not simply explained by any model. All standard model diagrams that can contribute to these decays are related by symmetries to diagrams…

We present a complete calculation of the Leading Order QCD corrections to the quark level decay amplitude for b -> s gamma gamma and study their relevance for both the inclusive branching ratio BR(B -> X_s gamma gamma) and for the exclusive…

Recent results include the measurement of B->D(*)pi+pi-pi-pi0 decays, with rates of ~1.8% observation of a significant omega pi^- substructure that appears to result from the decay of the rho' resonance, whose mass and width we determine as…