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Related papers: A Simple Model for the BFKL-DGLAP Transition

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We show that the gluon distribution function for very large nuclei may be computed for small transverse momentum as correlation functions of an ultraviolet finite two dimensional Euclidean field theory. This computation is valid to all…

High Energy Physics - Phenomenology · Physics 2009-10-22 Larry McLerran , Raju Venugopalan

We discuss the Wilson renormalization group approach to the effective action for low $x$ physics. It is shown that in the linearized, weak field regime the RG equation reduces to the BFKL equation for the evolution of the unintegrated gluon…

High Energy Physics - Phenomenology · Physics 2009-10-30 Jamal Jalilian-Marian , Alex Kovner , Andrei Leonidov , Heribert Weigert

We present the BFKL equation as a reggeon Bethe-Salpeter equation and discuss the use of reggeon diagrams to obtain 2-2 and 2-4 reggeon interactions at $O(g^4)$. We then outline the dispersion theory basis of multiparticle $j$-plane…

High Energy Physics - Phenomenology · Physics 2016-08-15 Claudio Corianò , Alan. R. White

New Results on the measurement of the proton structure function F_2(x,Q^2) are reported for momentum transfers squared Q^2 >= 1.5 GeV^2 and Bjorken x >= 3.5 10^{-5} using data collected by the HERA experiments H1 and ZEUS in 1994. F_2…

High Energy Physics - Experiment · Physics 2007-05-23 Gregorio Bernardi

The $F_{2}$, $F_{G}$, $R=F_{L}/F_{T}$ proton structure functions are derived in the QCD dipole picture of BFKL dynamics. We get a three parameter fit describing the 1994 H1 proton structure function $F_{2}$ data in the low $x$, moderate…

High Energy Physics - Phenomenology · Physics 2009-10-30 Ch. Royon

We examine the effect of using an angular ordered evolution equation for the unintegrated gluon distribution at small x.

High Energy Physics - Phenomenology · Physics 2009-10-30 G. Bottazzi

Order $\alpha_s$-corrections to the diffractive structure functions $F_L^D$ and $F_2^D$ at large $Q^2$ and small $x$ are evaluated in the semiclassical approach, where the initial proton is treated as a classical colour field. The…

High Energy Physics - Phenomenology · Physics 2009-02-20 W. Buchmuller , A. Hebecker , M. F. McDermott

Of late, the field of BFKL physics has been the subject of significant developments. The calculation of the NLL terms was recently completed, and they turned out to be very large. Techniques have been proposed to resum these corrections.…

High Energy Physics - Phenomenology · Physics 2014-11-17 Gavin P. Salam

We review small $x$ contributions to perturbative evolution equations for parton distributions, and their resummation. We emphasize in particular the resummation technique recently developed in order to deal with the apparent instability of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Guido Altarelli , Richard D. Ball , Stefano Forte

Explicit expressions for the singlet g_1 at small x and small Q^2 are obtained with the total resummation of the leading logarithmic contributions. It is shown that g_1 practically does not depend on Q^2 in this kinematic region. In…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. I. Ermolaev , M. Greco , S. I. Troyan

We present a set of formulae using the solution of the QCD Dokshitzer-Gribov-Lipatov-Altarelli-parisi (DGLAP) evolution equation to the extract of the exponent $\lambda_g$ gluon distribution and $\lambda_S$ structure function from the…

High Energy Physics - Phenomenology · Physics 2016-11-16 G. R. Boroun , B. Rezaei

Recently, an exact conformal mapping between soft gluons emitted from jets at large angle in e+e- annihilation and those in the BFKL evolution of a high energy hadron has been proposed. We elucidate some remarkable aspects of this…

High Energy Physics - Phenomenology · Physics 2010-02-25 Emil Avsar , Yoshitaka Hatta , Toshihiro Matsuo

We compute the distribution functions for gluons at very small x and not too large values of transverse momenta. We extend the McLerran-Venugopalan model by using renormalization group methods to integrate out effects due to those gluons…

High Energy Physics - Phenomenology · Physics 2009-10-28 Jamal Jalilian-Marian , Alex Kovner , Larry McLerran , Heribert Weigert

We present results for the structure function F_L for a gluon target having nonzero transverse momentum square at order \alpha_s. The results of double convolution (with respect to Bjorken variable x and the transverse momentum) of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. V. Kotikov , A. V. Lipatov , N. P. Zotov

We start from the two existing QCD evolution equations for structure functions, the BFKL and DGLAP equations, and discuss the theoretical hints for a unifying picture of the evolution in $x$ and $Q^2.$ The main difficulty is due to the…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Peschanski

The QCD dipole picture allows to build an unified theoretical description -based on BFKL dynamics- of the total and diffractive nucleon structure functions measured at HERA. We use a four parameter fit to describe the 1994 H1 proton…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Royon

We present a method for the analytic solution of small $x$ structure functions. The essential small $x$ logarithms are summed to all orders in the anomalous dimensions and coefficient functions. Although we work at leading logarithmic…

High Energy Physics - Phenomenology · Physics 2010-03-25 J. R. Forshaw R. G. Roberts R. S. Thorne

We present a detailed description of the Q^2 and x dependence of the structure functions F2 and FL as extracted from the Deep Inelastic Scattering data at HERA in the small Bjorken x region. Making use of a collinearly-improved BFKL…

High Energy Physics - Phenomenology · Physics 2013-04-10 Martin Hentschinski , Agustin Sabio Vera , Clara Salas

We calculate the gluon structure function of a color dipole in a new approach evaluating the matrix elements of SU(2) gluon field operators separated along a direction close to the light cone. As vacuum state in the pure glue sector, we use…

High Energy Physics - Phenomenology · Physics 2010-02-04 D. Grünewald , E. -M. Ilgenfritz , H. J. Pirner

The status of measurements and interpretation of the proton structure function F2 is summarized. The measurements are subjected to DGLAP fits, from which the gluon density is extracted and a comparison to measurements of F2c is performed.…

High Energy Physics - Experiment · Physics 2016-11-23 Christoph Amelung