相关论文: W-exchange and W-annihilation processes of B meson…
We calculate the semileptonic branching ratio and the charm counting of inclusive $B$ meson decays using the perturbative QCD formalism. For the nonleptonic decays, we employ the modified factorization theorem, in which Wilson coefficients…
With the generalized factorization approximation, we calculate the branching ratios and CP asymmetries in B meson decays into two charmless pseudoscalar mesons. We give a new estimation of the matrix elements of (S+P)(S-P) current products…
The role of $W$-exchange diagrams in baryonic $B$ decays is poorly understood, and often taken as insignificant and neglected. We show that charmful two-body baryonic $B\to {\bf B}_c \bar {\bf B}'$ decays provide a good test-bed for the…
Two-body charmless nonleptonic decays of the B_s meson are studied within the framework of generalized factorization in which factorization is applied to the tree level matrix elements while the effective Wilson coefficients are $\mu$ and…
We use currently available data of nonleptonic charmless 2-body $B\to MM$ decays ($MM = PP, PV, VV$) that are mediated by $b\to (d, s)$ QCD- and QED-penguin operators to study weak annihilation and new-physics effects in the framework of…
In this work, we investigate those $B_{c}\rightarrow D^{(*)}T$ decays in perturbative QCD approach, based on $k_T$ factorization, where T denotes a light tensor meson. For all decays considered in this work, there are no contributions from…
We have made an ab initio three-loop quark model calculation of the $W$-exchange contribution to the nonleptonic two-body decays of the doubly charmed baryons $\Xi_{cc}^{++}$ and $\Omega_{cc}^{+}$. The $W$-exchange contributions appear in…
We make a systematic investigation on the double charm decays of $B_c$ meson, by employing the perturbative QCD approach based on $k_T$ factorization. It is found that the non-factorizable emission diagrams are not negligible in these…
In recent studies of inclusive $B$ decays, it has been suggested that either $B$ mesons decay much more copiously to final states with no open charm than currently assumed, or $B(D^0 \to K^-\pi^+)$ has to be reduced significantly. This note…
We evaluate the W-exchange diagram within the framework of light cone sum rules (LCSR), taking $B_d^0 \to D_s^-K^+$ as an example. This decay mode, though proceeding via the W-exchange diagram only and therefore expected to be highly…
Exclusive semileptonic B decays to the lightest excited charmed mesons are investigated at order $\Lambda_{QCD}/m_Q$ in the heavy quark effective theory. At zero recoil, $\Lambda_{QCD}/m_Q$ corrections to the matrix elements of the weak…
Using the QCD factorization approach, we reexamine the two-body hadronic charmless $B$-meson decays to final states involving a pseudoscalar~($P$) and a vector~($V$) meson, with inclusion of the penguin contractions of spectator-scattering…
We calculate the decay rates of $B$ mesons into P-wave charmonium states using new factorization formulas that are valid to leading order in the relative velocity of the charmed quark and antiquark and to all orders in the running coupling…
The two-body mesonic $B$ decays induced only via a single $W$-exchange or annihilation quark diagram, such as $B^-_u\rightarrow D^{(*)-}_sK^{(*)0}$ and $\bar{B}^0_d\rightarrow D^{(*)+}_sK^{(*)-}$, are analyzed in the factorization…
The QCD factorization (QCDF) method usually contains infrared divergences which introduce large model dependence to its predictions on charmless B decays. The amplitudes of charmless B decays can be decomposed into "tree" and "penguin"…
We study the $B(B_{s})\rightarrow D_{(s)}(\bar{D}_{(s)})\,T$ and $D_{(s)}^{\ast}(\bar{D}_{(s)}^{*})\,T$ decays in perturbative QCD approach, where T denotes a light tensor meson. In addition to the branching ratios, we also give predictions…
We review several aspects of the phenomenology of P-wave $\bar q Q$ mesons: mass splittings, effective strong couplings and leptonic constants. We also describe a QCD sum rule determination to order $\alpha_s$ of the form factor…
Motivated by the recent measurement of the upper limit of ${B}^0 \to J/\psi D$ branching ratio, which is important in accounting for the soft $J/\psi$ production in B decays, we investigate ${B}^0 \to J/\psi D^{(\star)}$ and $\eta_c…
The perturbative QCD (PQCD) approach based on $k_T$ factorization has made a great achievement for the QCD calculation of the hadronic B decays. Regulating the endpoint divergence by the transverse momentum of quarks in the propagators, one…
In the heavy quark limit, both vector mesons in the charmless B -> VV decay should have zero helicity and the corresponding amplitude is proportional to the form factor difference $(A_1-A_2)$. The first observed charmless $B\to VV$ mode,…