Related papers: Perturbative QCD Analysis of Exclusive Processes $…
We discuss exclusive radiative decays in QCD factorization within the Standard Model. In particular, we consider the decays B -> V gamma, with a vector meson K* or rho in the final state, and the double radiative modes B_s -> gamma gamma…
We report the calculation of the process $e^+ e^- \to J/\psi J/\psi$ up to next-to-next-to-leading order (NNLO) at a center-of-mass (CM) energy of $\sqrt{s}=10.58$ GeV. We employ an improved NRQCD factorization approach, decomposing the…
The process $p\,p\hskip-7pt\hbox{$^{^{(\!-\!)}}$} \rightarrow W^{+} W^{-} + X \rightarrow \ell^+_1 \nu_1 \ell^-_2 \bar \nu_2 + X$ is calculated to ${\cal O}(\alpha_s)$ for general $C$ and $P$ conserving $WWV$ couplings ($V=\gamma,\, Z$).…
We calculate the $B_{u,d,s}\to T$ form factors within the framework of the perturbative QCD approach, where $T$ denotes a light tensor meson with $J^P=2^+$. Due to the similarities between the wave functions of a vector and a tensor meson,…
We compute perturbative QCD corrections to $B \to D$ form factors at leading power in $\Lambda/m_b$, at large hadronic recoil, from the light-cone sum rules (LCSR) with $B$-meson distribution amplitudes in HQET. QCD factorization for the…
We review recent developments in the perturbative QCD approach to exclusive hadronic B meson decays. We discuss the important next-to-leading-order corrections to B -> pi K, pi pi, and the penguin-dominated B -> PV modes, where P (V) is a…
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…
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 report the first complete leading-twist next-to-leading-order perturbative QCD predictions for the two-photon exclusive channels gamma gamma -> M+ M- (M=pi,K) at large momentum transfer. The asymptotic distribution amplitude is utilized…
We report searches for the processes $e^+e^-\to\pi^+\pi^-\pi^0\chi_{bJ}$ and $e^+e^-\to\phi\chi_{bJ}$ (J=1,2) based on data samples collected by the Belle experiment at the KEKB collider. We report the first observation of the process…
We explore the detection potential of the four lepton production processes $e^{+}e^{-} \rightarrow l^{+} \nu l^{\prime -}\overline{\nu}$ for anomalous contributions to the triple boson vertices at proposed future high energy colliders with…
We make a detailed study on the typical production channel of double charmoniums, $e^+e^-\to J/\psi+\eta_c$, at the center-of-mass collision energy $\sqrt{s}=10.58$ GeV. The key component of the process is the form factor $F_{\rm VP}(q^2)$,…
The exclusive photoproduction of a pair of light mesons is studied within the framework of collinear factorisation. The amplitude factorises into a process-dependent perturbatively calculable hard part, a generalised parton distribution…
The rare decay B^+ \to D_s^+ \bar K^{*0} can occur only via annihilation diagrams in the Standard Model. We calculate the branching ratio in perturbative QCD approach based on k_T factorization theorem. We found that the branching ratio of…
The study of top-quark properties will be a central aspect of the physics programme of any future lepton collider. In this article, we investigate the production of top-quark pairs in the semi-leptonic decay channel in $\rm e^+e^-$…
We study inclusive production of doubly heavy baryon at a $e^+e^-$ collider and at hadron colliders through fragmentation. We study the production by factorizing nonpertubative- and perturbative effects. In our approach the production can…
A search for the decay $B^+\to D_s^+ K^+K^-$ has been reported by the LHCb Collaboration using $pp$ collision data corresponding to an integrated luminosity of $4.8\,\mathrm{fb}^{-1}$, collected at center-of-mass energies of 7, 8, and…
Potential-NRQCD offers an effective-theory based approach to heavy-quark physics. While meson Q-anti_Q computations are tractable in pure alpha_s-perturbation theory, more complex many-body quark systems transcend it. A possibility…
We review our recent works on tests of perturbative QCD, inspired by the relation between the hadronic decay of the tau lepton and the e+ e- annihilation into hadrons. First, we present a set of commensurate scale relations that probe the…
This paper is a brief survey of the Balitskii-Fadin-Kuraev-Lipatov (BFKL) approach for the description of hard or semi-hard processes in the so-called Regge limit of perturbative QCD. The starting point is a fundamental property of…