相关论文: Factorization theorems for exclusive heavy-quarkon…
Within the nonrelativistic QCD (NRQCD) factorization framework, we have computed the ${\mathcal O}(\alpha_s^2)$ corrections to the exclusive production of $P$-wave spin-triplet charmonia $\chi_{cJ}(J=0,1,2)$ accompanied by a hard photon at…
Employing the QCD factorization formalism we compute $B_{u}^{-} \to \gamma^{\ast} \, \ell \, \bar \nu_{\ell}$ form factors with an off-shell photon state possessing the virtuality of order $m_b \, \Lambda_{\rm QCD}$ and $m_b^2$,…
Two-body decays of B mesons are studied by decomposing their amplitude into a sum of factorizable and non-factorizable ones. The former is estimated by using the naive factorization while the latter is calculated by using a hard pion (or…
Within the nonrelativistic quantum chromodynamics (NRQCD) factorization formalism, we compute the relativistic corrections to the exclusive decays of bottomonia with even charge conjugation parity into $S$-wave charmonium pairs at leading…
We discuss applications of the perturbative QCD approach in the exclusive non-leptonic two body B-meson decays. We briefly review its ingredients and some important theoretical issues on the factorization approaches. PQCD results are…
We study the exclusive decays of $B$ meson into pseudoscalar charmonium states $\eta_c$ and $\eta_c^\prime$ within the QCD factorization approach and find that the nonfactorizable corrections to naive factorization are infrared safe at…
We prove that in the limit $m_b, m_c\to\infty$ with $m_c/m_b$ fixed, factorization holds at order $\alpha_s$ for the decay $\Lambda_b^0\to\Lambda_c^+\pi^-$. This proof is done in the infinite-momentum frame in which the momenta of $\pi$,…
We discuss the production of two hadrons in e+e- annihilation within the framework of perturbative QCD. The cross section for this process is calculated to next-to-leading order accuracy with a selection of variables that allows the…
I review the theoretical ideas and concepts along the line of factorization in the exclusive B decays. In order to understand the naive factorization, the effective field theories and the perturbative method of QCD are introduced and…
In nonrelativistic QCD (NRQCD), we study $e^+ e^- \to J/\psi(\psi(2S)) +\chi_{c0}$ at $B$ factories, where the P-wave state $\chi_{c0}$ is associated with an S-wave state $J/\psi$ or $\psi(2S)$. In contrast to the failure of factorization…
I review recent progress on exclusive $B$ meson decays made in the perturbative QCD approach, concentrating on the evolution of the $B$ meson wave function in $k_T$ factorization, radiative decays, polarizations in $VV$ modes, and new…
We estimate the non-perturbative power-suppressed corrections to heavy flavour fragmentation and correlation functions in e^+e^- annihilation, using a model based on the analysis of one-loop Feynman graphs containing a massive gluon. This…
In order to clarify the puzzling problems in double charm production, relativistic corrections at order $v^{2}$ to the processes $e^{+}e^{-}\to J/\psi+\eta_{c}$ and $e^{+}e^{-}\to J/\psi+c\bar{c}$ at B factories are studied in…
We accomplish the analytical computation of the pure weak annihilation non-leptonic $B$-meson decay amplitudes at leading power in the heavy quark expansion. The novel observation regarding such fundamental hadronic quantities is that…
We study the exclusive production of scalar $S = 0^{++}$ and tensor $T = 2^{++}$ mesons through single-photon annihilation $e^+ e^- \to \gamma^* \to \gamma S(T)$. Using QCD compositeness of the involved hadrons considered as quark-antiquark…
The charmless bottom meson decays are systematically investigated based on an approximate six quark operator effective Hamiltonian from perturbative QCD. It is shown that within this framework the naive QCD factorization method provides a…
Most previous calculations of the annihilation decay rates of heavy quarkonium were based on factorization assumptions that were unproven and, in some cases, even incorrect. The recent development of a general factorization formula for…
In a typical exclusive quarkonium production process, when the center-of-mass energy, $\sqrt{s}$, is much greater than the heavy quark mass $m$, large kinematic logarithms of $s/m^2$ will unavoidably arise at each order of perturbative…
We study the production of isolated photons in $e^+e^-$ annihilation and give the proof of the all-order factorization of the collinear singularities. These singularities are absorbed in the standard fragmentation functions of partons into…
We calculate the next-to-leading order QCD corrections to the excited charmonium $\chi_{cJ}$ associated with $ W^+ b $ production from top-quark decay. Our results show that detecting the $\chi_{c0}$ production from top-quark decay is very…