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Related papers: Q2-evolution of parton densities at small-x values

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The combined HERA data for the inclusive deep inelastic scattering (DIS) cross sections for the momentum transfer $Q^2 > 1$ GeV$^2$ are fitted within the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) framework at next-to-leading order…

High Energy Physics - Phenomenology · Physics 2018-03-14 Leszek Motyka , Mariusz Sadzikowski , Wojciech Slominski , Katarzyna Wichmann

A modification of the saturation model of deep inelastic scattering at small x which includes the Altarelli-Parisi (DGLAP) evolution is presented. Significant improvement of the description of the structure function F_2 at large Q^2 is…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Bartels , K. Golec-Biernat , H. Kowalski

The Bessel-inspired behavior of parton densities at small Bjorken $x$ values, obtained in the case of the flat initial conditions for DGLAP evolution equations, is used along with "frozen" and analytic modifications of the strong coupling…

High Energy Physics - Phenomenology · Physics 2017-12-13 A. V. Kotikov , B. G. Shaikhatdenov , Pengming Zhang

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 computed the deep inelastic scattering (DIS) structure functions $F_2 (x,Q^2)$ and $F_L (x,Q^2)$ in the framework of Gribov-Levin-Ryskin-Mueller-Qiu, Zhu-Ruan-Shen (GLR-MQ-ZRS) equation. Both $x$ and $Q^2$ evolutions of the structure…

High Energy Physics - Phenomenology · Physics 2019-10-01 Madhurjya Lalung , Pragyan Phukan , Jayanta Kumar Sarma

We critically examine the QCD predictions for the $Q^2$ dependence of the electron-proton deep-inelastic structure function $F_2(x,Q^2)$ in the small $x$ region, which is being probed at HERA. The standard results based on next-to-leading…

High Energy Physics - Phenomenology · Physics 2010-03-25 A. J. Askew , K. Golec , J. Kwiecinski , A. D. Martin , P. J. Sutton

We critically analyse the data available on the reduced cross-section in deeply inelastic $e p$ scattering from the H1 collaboration at HERA. We use available data on the longitudinal structure function to deduce the nature of $\d F_2/\d\ln…

High Energy Physics - Phenomenology · Physics 2009-10-31 Rahul Basu , D. Indumathi

We investigate the evolution of parton densities at small values of the momentum fraction, x, by including resummed anomalous dimensions in the renormalization group equations. The resummation takes into account the leading-logarithmic…

High Energy Physics - Phenomenology · Physics 2016-09-01 R. K. Ellis , F. Hautmann , B. R. Webber

We investigate the effect of the structure function F_L in global parton analyses of deep inelastic and related hard scattering data. We perform NLO and NNLO analyses which include the reduced cross section HERA data at high y, as well as…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. D. Martin , W. J. Stirling , R. S. Thorne

We pursue the hypothesis that the events with a large rapidity gap, observed at HERA, reflect the scattering of electrons off lumps of wee partons inside the proton. A simple scaling behaviour is predicted for the diffractive structure…

High Energy Physics - Phenomenology · Physics 2009-10-28 Wilfried Buchmuller

We present measurements of the structure function \Ft\ in $e^+p$ scattering at HERA in the range $3.5\;\Gevsq < \qsd < 5000\;\Gevsq$. A new reconstruction method has allowed a significant improvement in the resolution of the kinematic…

High Energy Physics - Experiment · Physics 2012-08-27 ZEUS Collaboration

In the kinematic region of small $x$ and large $Q^2$ in deep inelastic scattering, presently being explored by HERA, we present an analysis of the evolution of the longitudinal structure function $F_L^{p}(x, Q^2)$ in the double scaling…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tapobrata Sarkar , Rahul Basu

We discuss how the proton structure function F2 is described in the HERA kinematic range by double asymptotic expressions for low x and large Q^2. From a NLO double asymptotic approximation of recent data from the H1 experiment at HERA we…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. DeRoeck , M. Klein , Th. Naumann

We present a global fit to the structure function F_2 measured in lepton-proton experiments at small values of Bjorken-x, x< 0.01, for all experimentally available values of Q^2, 0.045< Q^2 < 800 GeV^2, using the Balitsky -Kovchegov…

High Energy Physics - Phenomenology · Physics 2009-06-16 J. L. Albacete , N. Armesto , J. G. Milhano , C. A. Salgado

We present a set of formulae to extract the longitudinal deep inelastic structure function $F_L$ from the transverse structure function $F_2$ and its derivative $dF_2/dlnQ^2$ at small $x$. Our expressions are valid for any value of…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. V. Kotikov , G. Parente

We observe that the DGLAP evolution equations at NNLO analysis predicts a ratio of the structure functions in region of small Bjorken variable $x$. The ratio $F_{L}(x,Q^{2})/F_{2}(x,Q^{2})$ is obtained and compared with the prediction of…

High Energy Physics - Phenomenology · Physics 2019-08-09 G. R. Boroun , B. Rezaei

We recently derived explicit solutions of the leading-order Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) equations for the $Q^2$ evolution of the singlet structure function $F_s(x,Q^2)$ and the gluon distribution $G(x,Q^2)$ using very…

High Energy Physics - Phenomenology · Physics 2015-05-30 Martin M. Block , Loyal Durand , Phuoc Ha , Douglas W. McKay

We shown the general approach for Q2 evolution of parton densities and fragmentation functions at low x based on the diagonalization. The diagonalization leads to the two components in the Q2 evolution, each of which contains a…

High Energy Physics - Phenomenology · Physics 2015-02-26 Anatoly Kotikov

The QCD expectations concerning the deep inelastic lepton - hadron scattering at low $x$ and their phenomenological implications for HERA are summarised. Theoretical predictions for the structure function $F_2(x,Q^2)$ based on the leading…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Kwieciński

By introducing Q^2-dependence in resonance-reggeon "soft" dual models with nonlinear trajectories, they are extended to "hard" processes, sharing the property of parton-hadron duality. The resulting object is a two-component complex…

Nuclear Theory · Physics 2007-05-23 L. Jenkovszky , V. K. Magas , E. Predazzi