Related papers: Effective quark interactions from QCD
A general scheme is proposed here to describe the production of semi soft and soft quarks and gluons that form the bulk of the plasma in ultra relativistic heavy ion collisions. We show how to obtain rates as a function of time in a self…
A comprehensive determination of the quark mass dependence in the dispersion relations of thermal excitations of gluons and quarks in non-Abelian gauge theory (QCD) is presented for the one-loop approximation in Feynman gauge. Larger values…
We consider the Bjorken limit in the framework of the effective action approach and discuss its similarities to the Regge limit. The proposed effective action allows for a rather simple calculation of the known evolution kernels. We…
We introduce a nonperturbative interaction for light-cone fluctuations containing quarks and gluons. The $\bar qq$ interaction squeezes the transverse size of these fluctuations in the photon and one does not need to simulate this effect…
We discuss our present knowledge of $\alpha_s$, the fundamental running coupling or effective charge of Quantum Chromodynamics (QCD). A precise understanding of the running of $\alpha_s(Q^2) $ at high momentum transfer, $Q$, is necessary…
We discuss QCD condensate contributions to the gluon propagator both in the fixed-point gauge and in covariant gauges for the external QCD vacuum gluon fields with the conclusion that a covariant gauge is essential to obtain a gauge…
The transport interaction rates of elastic scattering processes of thermal partons in the quark-gluon plasma are calculated beyond the leading logarithm approximation using the effective perturbation theory for QCD at finite temperatures…
This paper applies the analytic forms of a recent non-perturbative, manifestly gauge- and Lorentz-invariant description (of the exchange of all possible virtual gluons between quarks ($Q$) and/or anti-quarks ($\bar{Q}$) in a quenched,…
In this review article, we develop the perturbative framework for the calculation of hard scattering processes. We undertake to provide both a reasonably rigorous development of the formalism of hard scattering of quarks and gluons as well…
An effective field theory describing the QCD diffraction scattering is constructed. The constituent quarks interacting with multiperi- pheral gluons and Goldstone bosons are described by impact- parameter two-dimensional sigma models for…
In this paper we propose an approach which demonstrates the dependence of quarkoni production on the multiplicity of the accompanying hadrons. Our approach is based on the three gluons fusion mechanism, without assuming the multiplicity…
I derive a general effective theory for hot and/or dense quark matter. After introducing general projection operators for hard and soft quark and gluon degrees of freedom, I explicitly compute the functional integral for the hard quark and…
We show that the form of the renormalization group invariant quark-gluon interaction predicted by a refined nonperturbative analysis of the QCD gauge sector is in quantitative agreement with the one required for describing a wide range of…
These lectures are an introduction to recent developments in the study of the high temperature phase of QCD by using weak coupling techniques. After a brief introduction to some techniques of quantum field theory at finite temperature, I…
We present here the first result on the three-loop gluon jet function in perturbative QCD. Using the three-loop coefficient functions [1,2] for deep-inelastic scattering via the exchange of a virtual photon that couples to quarks or a…
We implement our past investigations in the quark-antiquark interaction through a non-perturbative running coupling defined in terms of a gluon mass function, similar to that used in some Schwinger-Dyson approaches. This coupling leads to a…
We describe a number of aspects in our attempt to construct an approximately perfect lattice action for QCD. Free quarks are made optimally local on the whole renormalized trajectory and their couplings are then truncated by imposing…
We review the formalism of the effective average action in quantum field theory which corresponds to a coarse grained free energy in statistical mechanics. The associated exact renormalization group equation and possible nonperturbative…
The high-energy quark-quark scattering amplitude is calculated first in the case of scalar QCD, using Fradkin's approach to derive the scalar quark propagator in an external gluon field and computing it in the eikonal approximation. The…
Nonperturbative picture of strong interacting quark-gluon plasma is given based on the systematic Field Correlator Method. Equation of state, phase transition in density-temperature plane is derived and compared to lattice data as well as…