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Related papers: k-Factorization and Small-x Anomalous Dimensions

200 papers

We propose a matrix evolution equation in (x,kt)-space for flavour singlet, unintegrated quark and gluon densities, which generalizes DGLAP and BFKL equations in the relevant limits. The matrix evolution kernel is constructed so as to…

High Energy Physics - Phenomenology · Physics 2010-03-25 M. Ciafaloni , D. Colferai , G. P. Salam , A. M. Stasto

A survey is given of recent developments on the resummed small-$x$ evolution, in a framework based on the renormalization group equation, of non--singlet and singlet structure functions in both unpolarized and polarized deep--inelastic…

High Energy Physics - Phenomenology · Physics 2015-06-25 J. Blümlein , S. Riemersma , A. Vogt

We solve the BFKL equation in the leading logarithmic approximation numerically in the Yang-Mills theory with the Higgs mechanism for the vector boson mass generation. It can be considered as a model for the amplitude with the correct…

High Energy Physics - Phenomenology · Physics 2014-04-23 Eugene Levin , Lev Lipatov , Marat Siddikov

We obtain the quark and gluon rapidity anomalous dimension to fourth order in QCD. We calculate the N$^3$LO rapidity anomalous dimensions to higher order in the dimensional regulator and make use of the soft/rapidity anomalous dimension…

High Energy Physics - Phenomenology · Physics 2022-05-12 Claude Duhr , Bernhard Mistlberger , Gherardo Vita

The structure of the commutator algebra for conformal quantum mechanics is considered. Specifically, it is shown that the emergence of a dimensional scale by renormalization implies the existence of an anomaly or quantum-mechanical symmetry…

High Energy Physics - Theory · Physics 2007-05-23 Gino N. J. Ananos , Horacio E. Camblong , Carlos Gorrichategui , Ernesto Hernadez , Carlos R. Ordonez

I present a theoretical discussion of the uncertainties related to the QCD analysis of the proton structure function $F_2(x,Q^2)$ at small $x$. The role played by the `unphysical' gluon density is pointed out. It is shown how the study of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Stefano Catani

In this paper we proceed with the study of the Pomeron spectrum, by solving numerically the BFKL equation with massive gluons and running coupling. The spectrum of Regge singularities is discrete and the leading Pomeron has a considerable…

High Energy Physics - Phenomenology · Physics 2016-11-15 Eugene Levin , Lev Lipatov , Marat Siddikov

Non-perturbative corrections to hadronic observables represent a critical obstacle to increasing accuracy at colliders. Long taken to scale simply as $1/Q$, where $Q$ is the centre-of-mass scattering energy, recent work has opened the path…

High Energy Physics - Phenomenology · Physics 2025-07-28 Casey Farren-Colloty , Jack Helliwell , Rtvik Patel , Gavin P. Salam , Silvia Zanoli

Renormalizability of the (minimal) single-fermion QED extension is investigated at all orders of perturbation theory in the framework of algebraic renormalization, a regularization-independent method. Relative to the standard QED, new…

High Energy Physics - Theory · Physics 2015-06-04 O. M. Del Cima , J. M. Fonseca , D. H. T. Franco , A. H. Gomes , O. Piguet

We prove a set of identities for the anomalous dimensions of the quark and gluon conformal operators in the flavour singlet channel in QCD. These relations arise from the graded commutator algebra of the N=1 superconformal group. We…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. V. Belitsky , D. Muller , A. Schafer

We present a systematic formalism for the derivation of the kernel of the BFKL equation from that of the GLAP equation and conversely to any given order, with full inclusion of the running of the coupling. The running coupling is treated as…

High Energy Physics - Phenomenology · Physics 2010-03-25 Richard D. Ball , Stefano Forte

We investigate factorisation at small x using a variety of analytical and numerical techniques. Previous results on factorisation in collinear models are generalised to the case of the full BFKL equation, and illustrated in the example of a…

High Energy Physics - Phenomenology · Physics 2009-10-31 Marcello Ciafaloni , Dimitri Colferai , Gavin P. Salam

I present results for two-loop soft anomalous dimensions for heavy quark production which control soft-gluon resummation at next-to-next-to-leading-logarithm (NNLL) accuracy. I derive an explicit expression for the exact result and study it…

High Energy Physics - Phenomenology · Physics 2009-10-08 Nikolaos Kidonakis

The anomalous dimensions of the gluon and ghost fields as well as the ghost-ghost-gluon and quark-quark-gluon vertexes are analytically computed in pQCD. Taken together with already available anomalous dimensions of the coupling constant,…

High Energy Physics - Phenomenology · Physics 2010-04-05 K. G. Chetyrkin

We calculate DIS-scheme splitting and coefficient functions for electromagnetic deep inelastic scattering with small x resummations, as given by the NLL BFKL equation with running coupling and approximate NLL resummed impact factors. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. D. White , R. S. Thorne

We extend the resummation of dimensionally-regulated amplitudes to next-to-next-to-leading poles. This requires the calculation of two-loop anomalous dimension matrices for color mixing through soft gluon exchange. Remarkably, we find that…

High Energy Physics - Phenomenology · Physics 2009-04-06 S. Mert Aybat , Lance J. Dixon , George Sterman

We find the BFKL Pomeron intercept at N=4 supersymmetric gauge theory in the form of the inverse coupling expansion j0=2-2/lambda**(1/2)-1/lambda + 1/4 1/lambda**(3/2) + 2(1+3zeta3)/lambda**(2) + O(1/lambda**(5/2)) with the use of the…

High Energy Physics - Theory · Physics 2015-06-12 A. V. Kotikov , L. N. Lipatov

Renormalized Hamiltonians for gluons are constructed using a perturbative boost-invariant renormalization group procedure for effective particles in light-front QCD, including terms up to third order. The effective gluons and their…

High Energy Physics - Theory · Physics 2009-10-31 Stanislaw D. Glazek

In the framework of renormalon consideration, a role of the anomalous dependence of gluon propagator on the scale $\mu$ is shown for a large number of quark flavours as well as in the nonabelian theory, where the parameter of the "running"…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. V. Kiselev

In this paper we encode the perturbative BFKL leading logarithmic resummation, relevant for the Regge limit behavior of QCD scattering amplitudes, in the IR-regulated effective action which satisfies exact functional renormalization group…

High Energy Physics - Phenomenology · Physics 2019-01-30 J. Bartels , C. Contreras , G. P. Vacca