相关论文: Hard-soft factorization in B_c--> psi pi decay
Though QCD Factorization(QCDF) could produce sufficiently large $B\to K\pi$ branching ratios close to experiments, the predicted direct CP asymmetry in ${\bar B}^{0}\to K^{+}\pi^{-}$ decay is however still quite below experiment, even with…
General relations between the form factors of B decays to light mesons are derived using the heavy quark and large recoil expansion. On their basis the complete account of contributions of second order in the ratio of the light meson mass…
The mass relation ${M_{0^{+}}+3M_{1^{+\prime}}+5M_{2^{+}}= 9M_{1^{+}}}$ miraculously holds for the $P$-wave charmonium $(c\bar{c})$ and bottomonium $(b\bar{b})$ systems with soaring precision. The origin of such relation can be addressed…
It is very important to know the strength of annihilation contribution in B charmless nonleptonic decays. $\bar{B}_{s}\to \pi^{+}\pi^{-}$ process could serve a good probe of the strength. We have studied the process in QCD factorization…
Motivated by recent interest in soft $J/\Psi$ production in B decays, we investigate ${B}^0 \to J/\Psi D^{(\star)}$ and $\eta_c D^{(\star)}$ decays in perturbative QCD. We find that, within that framework, these decays are calculable since…
Nonleptonic decays B to D pi- or B to D* pi- are dominated by factorizable contributions. In the heavy quark limit, nonfactorizable contribution arises from strong radiative correction and power corrections in 1/m_b. I calculate the decay…
The hadronic decays of quarkonium and the B meson inclusive decay into J/Psi + X, if treated in the zero-binding approximation, suggest a value of the strong coupling constant much smaller than the value implied in the standard model by…
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"…
The decay constant for the vector state of $3S$-level in the heavy $(\bar b c)$-quarkonium is evaluated in the framework of sum rules for the mesonic currents. A scaling relation for the constants of vector quarkonia with different quark…
Inspired by recent BESIII's amplitude analysis on $D_s^+\to\pi^+\pi^0\pi^0$, we develop a model based on the chiral unitary approach to discribe the $D_s^+\to\pi^+\pi^0\pi^0$ decay, where $D_s^+$ decays into a $\pi^+$ and a quark-antiquark…
The scale of low energy c-cbar and b-bbar cross sections on light hadrons is of great importance to searches for the quark gluon plasma using the heavy-quarkonium suppression signature. Unfortunately, little is known about these…
A baryonic decay of the $B_c^+$ meson, $B_c^+\to J/\psi p\overline{p}\pi^+$, is observed for the first time, with a significance of $7.3$ standard deviations, in $pp$ collision data collected with the LHCb detector and corresponding to an…
Progress in the theoretical description of B-meson decays, in particular decays to light hadrons, is reviewed. The factorization properties of such decays can be analyzed using the soft-collinear effective theory. Applications of the…
We have studied charmless hadronic decays of B mesons into two-body final states with kaons and pions and observe three new processes with the following branching fractions: BR(B-> pi+ pi-) = (4.3^{+1.6}_{-1.4} \pm 0.5) \times 10^{-6},…
We consider the exclusive decay $B\to J/\psi K$ using the QCD-improved factorization method in the heavy quark limit. It is shown that the decay amplitude is factorizable in this limit and nonfactorizable contributions are calculable from…
In this work, the soft rescattering parameters in the $B^\pm\rightarrow \pi^\pm\pi^+\pi^-$ and $B^\pm\rightarrow K^\pm\pi^+\pi^-$ decays with the light scalar meson $f_0(500)$ as the intermediate resonance are studied within the QCD…
We study $B\to \pi\pi$ decay with a modified perturbative QCD approach. The branching ratios and $CP$ violation are calculated with the transverse momenta of partons considered. Sudakov factor associated with each meson is included to…
Inspired by the small longitudinal polarizations (LPs) of $B\to K^* \phi$ decays observed by BELLE and BABAR, we revise the theoretical uncertainties of perturbative QCD approach for determining hard scales of B decays, we find that the LPs…
We study the polarization of the J/\psi meson of the B_c -> J/\psi mu nu decay process, followed by J/\psi -> mu+ mu-, with the help of the heavy-quark spin symmetry formalism (HQSS). We adapt the ISGW wave function. Due to the clean…
We study the two-body and three-body charmful baryonic B decays: $\bar B^0\to \Lambda_c\bar p$ and $\bar B\to \Lambda_c \bar p\pi(\rho)$. The factorizable W-exchange contribution to $\bar B^0\to\Lambda_c\bar p$ is negligible. Applying the…