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Related papers: Extrapolating Structure Functions to Very Small x

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We investigate the Q^2 evolution of parton distributions at small x values, obtained in the case of flat initial conditions. The contributions of twist-two and (renormalon-type) higher-twist operators of the Wilson operator product…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. V. Kotikov , G. Parente

In this paper, the evolutions of longitudinal proton structure function have been obtained at small-$x$ up to next-to-next-to-leading order using a hard Pomeron behavior. In our paper, evolutions of gluonic as well as heavy longitudinal…

High Energy Physics - Phenomenology · Physics 2014-12-05 G. R. Boroun , B. Rezaei , J. K. Sarma

We give a detailed account of the phenomenology of all-order resummations of logarithmically enhanced contributions at small momentum fraction of the observed hadron in semi-inclusive electron-positron annihilation and the time-like scale…

High Energy Physics - Phenomenology · Physics 2017-03-15 Daniele P. Anderle , Tom Kaufmann , Felix Ringer , Marco Stratmann

The Pauli exclusion principle is advocated for constructing the proton and neutron deep inelastic structure functions in terms of Fermi-Dirac distributions that we parametrize with very few parameters. It allows a fair description of the…

High Energy Physics - Phenomenology · Physics 2010-11-01 C. Bourrely , J. Soffer

We discuss the quantitative consequences of the resummation of the small-x contributions to the anomalous dimensions beyond next-to-leading order in alpha_s and up to next order in ln(1/x) (NLx) in a framework based on the renormalization…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Blümlein , V. Ravindran , W. L. van Neerven , A. Vogt

In this paper t and x-evolutions of gluon distribution function from Dokshitzer-Gribov-Lipatov-Altarelli-Parisi(DGLAP) evolution equation in leading order(LO) at low-x, assuming the Regge behaviour of quark and gluon at this limit, are…

High Energy Physics - Phenomenology · Physics 2014-11-18 U. Jamil , J. K. Sarma

We obtain an approximate analytical form of the gluon distribution using the GLAP equation with a factorization ansatz,and test its validity by comparing it with that of Gluck,Reya and Vogt at low $x$ regime. We also present calculations of…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ranjita Deka , D. K. Choudhury

We derive the evolution equations of parton distribution functions appropriate in different kinematic regions in a unified and simple way using the resummation technique. They include the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi equation…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hsiang-nan Li

This talks examines the effect of angular ordering on the small-x evolution of the unintegrated gluon distribution, and discusses the characteristic function for the CCFM equation.

High Energy Physics - Phenomenology · Physics 2009-10-30 G. P. Salam

The spin structure function $g_1^p$ of the proton is studied in a two component framework, where the perturbative evolution of parton distributions and nonperturbative vector meson dominance model are used. We predict the $g_1^p$ asymmetric…

High Energy Physics - Phenomenology · Physics 2015-03-10 Wei Zhu , Jianhong Ruan

This talks examines the effect of angular ordering on the small-x evolution of the unintegrated gluon distribution, and discusses the characteristic function for the CCFM equation.

High Energy Physics - Phenomenology · Physics 2016-11-03 M. Scorletti

I explicitly calculate the anomalous dimensions and splitting functions governing the Q^2 evolution of the parton densities and structure functions which result from the running coupling BFKL equation at LO, i.e. I perform a resummation in…

High Energy Physics - Phenomenology · Physics 2009-11-07 R. S. Thorne

Perturbative NLO and NNLO QCD evolutions of parton distributions are studied, in particular in the (very) small-$x$ region, where they are in very good agreement with all recent precision measurements of $F_2^p(x,Q^2)$. These predictions…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Glück , C. Pisano , E. Reya

I review recent results by Fadin,Lipatov and collaborators and by our group,leading to the almost complete calculation of the next-to-leading BFKL kernel,of its eigenvalues,and of the resummed gluon anomalous dimension. Qualitative…

High Energy Physics - Phenomenology · Physics 2007-05-23 Marcello Ciafaloni

Evolution of gluon distribution function from Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equation in next-to-leading order (NLO) at low-x is presented assuming the Regge behaviour of quarks and gluons at this limit. We…

High Energy Physics - Phenomenology · Physics 2010-03-25 U. Jamil , J. K. Sarma

After a brief introduction to low-x QCD and to resummation approaches, I illustrate the predictions for the gluon Green function and splitting function of a recent renormalization-group improved small-x resummation scheme. I argue, on this…

High Energy Physics - Phenomenology · Physics 2014-11-17 Marcello Ciafaloni

We analyze the perturbative and parametric stability of the QCD predictions for the Callan-Gross ratio $R(x,Q^2)=F_L/F_T$ in heavy-quark leptoproduction. We consider the radiative corrections to the dominant photon-gluon fusion mechanism.…

High Energy Physics - Phenomenology · Physics 2009-03-24 N. Ya. Ivanov , B. A. Kniehl

At small-x, the structure function F_L(x,Q2) is driven by the gluon content of the nucleon target and consequently it can unravel the underlying QCD dynamics in that region. In this work, one studies its behavior on photon virtuality Q2 at…

High Energy Physics - Phenomenology · Physics 2009-11-11 Magno V. T. Machado

The gluon distribution is obtained from the Golec-Biernat-W$\ddot{\mathrm{u}}$sthoff (GBW) and Bartels, Golec-Biernat and Kowalski (BGK) models at low $x$. We derive analytical results for the unintegrated color dipole gluon distribution…

High Energy Physics - Phenomenology · Physics 2025-09-24 G. R. Boroun

We discuss the inclusion of running coupling effects in perturbative small x evolution equations. We show that a running coupling BFKL-like x-evolution equation is fully compatible, up to higher twist corrections, with the standard…

High Energy Physics - Phenomenology · Physics 2008-11-26 Guido Altarelli , Richard D. Ball , Stefano Forte