Related papers: Three-loop matching coefficients for heavy flavor-…
Non-relativistic QCD is applied for a lattice computation of the heavy-light meson decay constant in quenched approximation at $\beta=6.0$. Clear signals are obtained for the ground state at large times in the correlators, allowing a…
The baryon axial vector current is computed at one-loop order in large-N_c baryon chiral perturbation theory, where N_c is the number of colors. Loop graphs with octet and decuplet intermediate states are systematically incorporated into…
We revisit the calculation of nonfactorizable corrections induced by charm-quark loops in exclusive FCNC $B$-decays. For the sake of clarity, we make use of a field theory with scalar particles: this allows us to focus on the conceptual…
We study the full contributions at the leading order(LO) and QCD next-to-leading order(NLO) to the cross section of the \eewwbb process in the standard model(SM) at the ILC. In dealing the resonance problem we adopted the complex mass…
We have calculated the step scaling function and the running coupling of QCD in the Schroedinger functional scheme with four flavors of O(a) improved Wilson quarks. Comparisons of our non-perturbative results with 2-loop and 3-loop…
We compute the three-loop QCD corrections to the massive quark-anti-quark-photon form factors $F_1$ and $F_2$ in the large-$N_c$ limit. The analytic results are expressed in terms of Goncharov polylogarithms. This allows for a…
We study the next-to-next-to-leading order (NNLO) evolution of flavour non-singlet quark densities and structure functions in massless perturbative QCD. Present information on the corresponding three-loop splitting functions is used to…
In this paper we compute the NLO QCD corrections for the inclusive nonleptonic decay rates of $B$-hadrons at subleading power of the heavy quark expansion. In particular, we discuss the coefficient of the chromomagnetic moment parameter…
The effective renormalizable theory describing electromagnetic and strong interactions of quarks of five light flavors ($n_f = 5$ QCD$\times$QED) is considered as a low-energy limit of the full Standard Model. Two-loop relation between the…
We compute the full three-loop coefficient functions for the structure functions F_2 and F_L in massless perturbative QCD. The results for F_L complete the next-to-next-to-leading order description of unpolarized electromagnetic…
A survey is given on the status of 3-loop heavy flavor corrections to deep-inelastic structure functions at large enough virtualities $Q^2$.
We calculate the four-loop massless QCD corrections with three closed quark lines to quark and gluon form factors. We apply a novel integration by parts algorithm based on modular arithmetic and compute all relevant master integrals for…
We calculate the complete NNLO QCD corrections to the charm contribution of the rare decay K+ -> pi+ nu nu-bar. We encounter several new features, which were absent in lower orders. We discuss them in detail and present the results for the…
We propose a new strategy for the determination of the QCD coupling. It relies on a coupling computed in QCD with $N_{\rm f} \geq 3$ degenerate heavy quarks at a low energy scale $\mu_{\rm dec}$, together with a non-perturbative…
QCD evolution equations in minimal subtraction schemes have a hidden symmetry: One can construct three operators that commute with the evolution kernel and form an $SL(2)$ algebra, i.e. they satisfy (exactly) the $SL(2)$ commutation…
We calculate the next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to double charmonium production processes $e^+e^-\to\gamma^*\to\eta_c+h_c(1P)/\psi_{1,2}(1D)$ within the non-relativistic QCD (NRQCD) factorization…
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…
An equivariant BRST-construction is used to define the continuum SU(3) gauge theory on a finite torus. I corroborate previous results using renormalization group techniques by explicitly computing the measure on the moduli-space of the…
We calculate the thermodynamic functions of a quark-gluon plasma for general N_c and N_f to three-loop order using hard-thermal-loop perturbation theory. At this order, all the ultraviolet divergences can be absorbed into renormalizations…
One-loop matching of heavy-light currents is carried out for a highly improved lattice action, including the effects of dimension 4 O(1/M) and O(a) operators. We use the NRQCD action for heavy quarks, the Asqtad improved naive action for…