Related papers: Hard spectator interactions in B to pi pi at order…
Based on the compilation of the available e^+e^- data, we present a non-perturbative estimation of the Adler function derived from the electromagnetic current correlator, and compare it with theoretical predictions from perturbative QCD…
We compute the momentum diffusion coefficient of a nonrelativistic heavy quark in a hot QCD plasma, to next-to-leading order in the weak coupling expansion. Corrections arise at O(g); physically they represent interference between…
Power-suppressed corrections coming from the end-point integration regions in the amplitude of the process $\gamma^{*}\gamma \to \pi \pi$ at large $Q^2$ and small squared center-of-mass energy $W^2$ are calculated in the QCD hard-scattering…
By employing the perturbative QCD(pQCD) factorization approach, we calculated the partial next-to-leading order (NLO) contributions to $B_s \to P P$ decays ($P= \pi, K, \etap $), coming from the QCD vertex corrections, the quark-loops and…
In this paper, we calculate the next-to-leading-order (NLO) twist-3 contribution to the form factors of $B \to \pi$ transitions by employing the $k_{T}$ factorization theorem. All the infrared divergences regulated by the logarithms…
In this paper, we investigate the contributions of hard spectator scattering and annihilation in $B\to PV$ decays within the QCD factorization framework. With available experimental data on $B\to \pi K^{\ast}$, $\rho K$, $\pi \rho$ and…
Based on the NRQCD factorization formalism, we calculate the next-to-next-to-leading order QCD corrections to the heavy quarkonium $\eta_c (\eta_b)$ production associated with a photon at electron-positron colliders. By matching the…
The QCD running coupling $\alpha_s(Q^2)$ sets the strength of the interactions of quarks and gluons as a function of the momentum transfer $Q$. The $Q^2$ dependence of the coupling is required to describe hadronic interactions at both large…
We present a complete analysis of the Heavy Quark Effective Theory Lagrangian at order $1/m^2$ in the leading logarithmic approximation, including effects induced by spectator quarks. At this order new correction terms appear in the…
We present the first calculation of next-to-leading order (NLO) factorized QED and QCD contributions to the short-distance hard coefficients of inclusive lepton-hadron deep inelastic scattering (DIS) in a joint QED and QCD factorization…
The next-to-next-to-leading order (NNLO) QCD analysis of the revised experimental data of the CCFR collaboration for the $xF_3$ structure function of the deep-inelastic scattering of neutrinos and antinuetrinos on the nucleons is made by…
We calculate the branching ratios of $B\to K_1\gamma$ at next-to-leading order (NLO) of $\alpha_s$ where $K_1$ is the orbitally excited axial vector meson. The NLO decay amplitude is divided into the vertex correction and the hard spectator…
We determine the full mass and $q^2$ dependence of the heavy quark vacuum polarization function $\Pi(q^2)$ and its contribution to the total $e^+e^-$ cross section at ${\cal O}(\alpha_s^2)$ and ${\cal O}(\alpha_s^3)$ in perturbative QCD. We…
We investigate the $B\to\pi\rho$ and $\pi\omega$ decay processes using the modified perturbative QCD (PQCD) approach. Sudakov factors arising from the resummation of the double logarithms for the contributions of the transverse momenta of…
By employing the perturbative QCD(pQCD) factorization approach, we calculate the branching ratios and CP violating asymmetries of the four $\bar{B}_s^0 \to K\pi$ and $K K $ decays, with the inclusion of all known next-to-leading order (NLO)…
We obtain relations between partial-wave amplitudes for pi-N-->pi-N and pi-N-->pi-Delta directly from large N_c QCD. While linear relations among certain amplitudes holding at leading order (LO) in 1/N_c were derived in the context of…
The propagation of long-wavelength gluons through a dense QCD medium at high baryon chemical potential mu_B is qualitatively modified by the effects of screening, arising from scatterings off the high-momentum quarks in the medium. This…
We update QCD calculations of $B \to \pi, K$ form factors at large hadronic recoil by including the subleading-power corrections from the higher-twist $B$-meson light-cone distribution amplitudes (LCDAs) up to the twist-six accuracy and the…
We calculate the $B\to P$, $B\to V$ (P: light pseudoscalar meson, V light vector meson) form factors in the large-recoil limit in perturbative QCD approach, including both the vector (axial vector) and tensor operators. In general there are…
The renormalon calculus is used to calculate the terms of order $\beta_0^{n-1}\alpha_s^n$ in the perturbative expansions of the Wilson coefficients and hard-scattering kernels entering the QCD factorization formula for hadronic B-meson…