相关论文: Two-point correlation functions of QCD in the Land…
Fundamental quantities of QCD, such as the strong coupling and $\Lambda_{QCD}$, are studied in the framework of lattice QCD with $N_f=2$ twisted mass fermions. In particular, the contact between lattice and continuous calculations is made…
We present a numerical study of the running coupling constant and of the gluon and ghost propagators in minimal Landau gauge. Simulations are done in pure SU(2) lattice gauge theory for several values of beta and lattice sizes. We use two…
We consider the gluon propagator in the Landau gauge at low spacelike momenta and with the dressing function $Z(Q^2)$ at the two-loop order. We incorporate the nonperturbative effects by making the (noninteger) powers of the QCD coupling in…
We report preliminary results of our ongoing lattice computation of the Landau gauge quark propagator and the soft gluon limit of the quark-gluon vertex with 2 flavors of dynamical O(a) improved Wilson fermions.
We continue the systematic computation of Landau gauge gluon and ghost propagators of SU(2) gluodynamics using a sequence of increasing lattice sizes L^4 up to L=112 with corresponding \beta-values chosen to keep the linear physical size…
In view of the expectation that the existence of complex poles is a signal of confinement, we investigate the analytic structure of the gluon, quark, and ghost propagators in the Landau gauge QCD and QCD-like theories by employing an…
We study the long-distance properties of quantum chromodynamics in an expansion in powers of the three-gluon, four-gluon, and ghost-gluon couplings, but without expanding in the quark-gluon coupling. This is motivated by two observations.…
Analytical functions for the propagators of QCD, including a set of chiral quarks, are derived by a one-loop massive expansion in the Landau gauge, and are studied in Minkowski space, yielding a direct proof of positivity violation and…
The infrared behaviour of the gluon and ghost propagators in Landau gauge QCD is reviewed. The Kugo-Ojima confinement criterion and the Gribov-Zwanziger horizon condition result from quite general properties of the ghost Dyson-Schwinger…
The gluon propagator in the Landau gauge is calculated in quenched QCD on a large lattice (32^3x64) at beta=6.0. In order to assess finite volume and finite lattice spacing artefacts, we also calculate the propagator on a smaller volume for…
Nonperturbative properties of gluons are studied in SU(3) lattice QCD at the quenched level. The first subject is a functional-form analysis of the gluon propagator $D_{\mu\nu}^{ab}(x)$ in the Landau gauge. We find that the gluon propagator…
The quenched Landau gauge gluon propagator is investigated in lattice QCD with large assimetric lattices, accessing momenta as low as $q \sim 100$ MeV or smaller. Our investigation focus on the IR limit of the gluon dressing function,…
By considering the scaling behaviour of various Feynman graphs at leading order in large $\Nf$ at the non-trivial fixed point of the $d$-dimensional $\beta$-function of QCD we deduce the critical exponents corresponding to the quark, gluon…
We present a numerical study of the space-space and time-time components of the gluon propagator at equal time in the minimal Coulomb gauge, and of the gluon and ghost propagators in the minimal Landau gauge. This work allows a…
In this paper we construct the Wilson short distance operator product expansion for the gluon, quark and ghost propagators in QCD, including operators of dimension two and three, namely, A^2, m^2, m A^2, \ovl{\psi} \psi and m^3. We compute…
In gauge field theories with asymptotic freedom, the short distance properties of Green's functions can be obtained on the basis of weak coupling perturbation expansions. Within this framework, the large momentum behavior of the structure…
We report on the lattice computation of the quark propagator at finite temperature in the Landau gauge, using quenched gauge configurations. The propagator form factors are computed for various temperatures, above and below the gluon…
We compute the gluon and ghost propagators of Yang-Mills theory in linear covariant gauges from the coupled system of Dyson-Schwinger equations. For small values of the gauge fixing parameter $\xi\sim 0.1$, the deviations to the Landau…
In this article we use the Schwinger-Dyson equations to compute the nonperturbative modifications caused to the infrared finite gluon propagator (in the Landau gauge) by the inclusion of a small number of quark families. Our basic operating…
The infrared behavior of gluon and ghost propagators in Yang-Mills theories is of central importance for understanding quark and gluon confinement in QCD. While simulations of pure SU(3) gauge theory correspond to the physical case in the…