The gluon spin coupling to a Gaussian correlated background gauge field induces an effective tachyonic gluon mass. It is momentum dependent and vanishes in the UV only like 1/p2. In the IR, we obtain stabilization through a positive mconf(p 2) related to confinement. Recently a purely phenomenological tachyonic gluon mass was used to explain the linear rise in the qq̄ static potential at small d...

Renormalization of twist-three operators and integrable lattice models. Abstract We address the problem of solution of the QCD three-particle evolution equations which govern the Q 2-dependence of the chiral-even quark-gluon-quark and three-gluon correlators contributing to a number of asymmetries at leading order and the transversely polarized structure function g 2 (x Bj). The quark-gluon-qua...

We study the properties of gluons in QCD in the maximally abelian (MA) gauge. In the MA gauge, the off-diagonal gluon behaves as the massive vector boson with the mass Moff ' 1.2 GeV, and therefore the off-diagonal gluon cannot carry the long-range interaction for r M−1 off ' 0.2 fm. The essence of the infrared abelian dominance in the MA gauge is physically explained with the generation of the...

Parton distribution functions in the nucleons have been obtained primarily through lepton-induced deep-inelastic scattering (DIS) experiments. One of the most important unresolved issues in our current knowledge of parton distributions is the role of gluons for describing the nucleon spin. While gluon polarization, ∆G(x), could in principle be deduced from the Q-evolution of the polarized struc...

We utilise the fact that the CCFM equation in the single loop approximation can be diagonalised by the Fourier-Bessel transform. The analytic solution of the CCFM equation for the moments fω(b,Q) of the scale dependent gluon distribution is obtained, where b is the transverse coordinate conjugate to the transverse momentum of the gluon. The unintegrated gluon distributions obtained from this so...

In exclusive J/ψ production by polarized photons incident on polarized protons , a finite polarization asymmetry arises because of c¯ c Fermi-motion and binding-energy effects. The asymmetry depends on the polarized nonfor-ward gluon distribution of the proton and thus gives information on gluon polarization in the proton. The analyzing power, however, is rather small. Gluon polarization in the...

We explore the analytic structure of the gluon and quark propagators of Landau gauge QCD from numerical solutions of the coupled system of renormalized Dyson–Schwinger equations and from fits to lattice data. We find sizable negative norm contributions in the transverse gluon propagator indicating the absence of the transverse gluon from the physical spectrum. A simple analytic structure for th...

QCD perturbation theory using quark and gluon propagators that have an extra term at zero four-momentum is equivalent to standard PQCD in the presence of massless quark and gluon pairs in the perturbative vacuum. We verify at low orders in perturbation theory that 〈ψψ〉 6 = 0 and that quarks acquire a constituent mass. Thus chiral symmetry is spontaneously broken, and the conservation of the axi...