Related papers: Longitudinal loop integrals in the gauge invariant…
We study integrations over light-cone momenta in the gauge invariant effective action of high energy QCD. A regularization mechanism which allows for the evaluation of the longitudinal integrations is presented. After a rederivation of the…
In this contribution we briefly review some aspects of Lipatov's gauge invariant QCD high energy effective action. The high energy effective provides a field theory framework to systematically factorize QCD scattering amplitudes and related…
The effective action for reggeized gluons is based on the gluodynamic Yang-Mills Lagrangian with external current for longitudinal gluons added, see [1]. On the base of classical solutions, obtained in [2], the one-loop corrections to this…
We study integrations over light-cone momenta in the high energy effective action of QCD. After a review of the effective action, we arrive on a regularization mechanism from matching with QCD diagrams, which we apply to a re-derivation of…
The Born amplitudes for quasi-multi-Regge kinematics of produced gluons are constructed in accordance with the Feynman rules including apart from usual Yang-Mills vertices also an infinite number of induced vertices. The new vertices…
Application of the effective action approach to amplitudes with loop integration is studied for collisions on two and three centers with possible gluon emission. A rule is formulated for the integration around pole singularities in the…
At 2-loop order, Feynman integrals in the Coulomb gauge are divergent over the internal energy variables. Nevertheless, it is known how to calculate the effective action provided that the external gluon fields are all transverse. We show…
We investigate the derivation of reggeon transition vertices from Lipatov's gauge invariant effective action for high energy processes in QCD. In particular we address the question of longitudinal integrations in order to reduce the…
Application of the effective action formalism is studied for processes in which the reggeons may split. It is shown that the gluon production on two centers is described by the contribution of the Reggeon-to-two-Reggeons-plus-Particle…
We present the derivation of the two-loop gluon Regge trajectory using Lipatov's high energy effective action and a direct evaluation of Feynman diagrams. Using a gauge invariant regularization of high energy divergences by deforming the…
Starting from the effective action of high energy QCD we derive Ward identities for Green's functions of reggeized gluons. They follow from the gauge invariance of the effective action, and allow to derive new representations of amplitudes…
New terms are derived for the three-dimensional effective action of the static modes of pure gauge SU(N) at high temperature. In previous works, effective vertices have been obtained by evaluating diagrams involving 2, 3 or 4 external…
We study QCD in the regime of high parton density arising in hadronic collisions at large center-of-mass energy. The n-gluon amplitudes of the generalized leading logarithmic approximation are investigated. We find identities relating…
An efficient numerical algorithm to evaluate one-loop amplitudes using tensor integrals is presented. In particular, it is shown by explicit calculations that for ordered QCD amplitudes with a number of external legs up to 10, its…
The effective action with homogeneous valence (off-diagonal) gluons as background fields in the extended SU(2) model of QCD is obtained in one-loop approximation. We keep the manifest gauge and Lorentz invariance during whole calculation by…
We perform an integral reduction for the 3-loop effective gauge coupling and screening mass of QCD at high temperatures, defined as matching coefficients appearing in the dimensionally reduced effective field theory (EQCD). Expressing both…
We investigate Lipatov's QCD effective action for the QCD high energy limit and propose a pole prescription for higher order induced vertices. The latter can be used in the evaluation of loop corrections to high energy factorized matrix…
The computation of one-loop corrections to the $\gamma^\star Q_+ q$ and $gR_+g$ effective vertices in the framework of gauge-invariant effective theory for Multi-Regge processes in QCD is reviewed. Due to consistent implementation of the…
We compute the one-loop QCD amplitude for the process gg-->Q\bar{Q} in dimensional regularization through order \epsilon^2 in the dimensional regulator and for arbitrary quark mass values. This result is an ingredient of the NNLO…
Gauge invariant correlators in QCD are studied on the lattice.A Systematic determination of the correlation lengths for gluon field strength correlators and quark correlators is made.The measurement of the gluon and quark condensates is…