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Related papers: Critical tests of unintegrated gluon distributions

200 papers

Recent progresses of the proton structure measurements and determination of parton distribution functions by $ep$ collisions at HERA are introduced.

High Energy Physics - Experiment · Physics 2019-08-14 Kunihiro Nagano

A measurement of the inclusive cross section for the deep-inelastic scattering of positrons off protons at HERA is presented at momentum transfers $8.5 \leq Q^2 \leq 35 GeV^2$ and large inelasticity $y = 0.7$, i.e. for the Bjorken-x range…

High Energy Physics - Experiment · Physics 2010-03-25 C. Adloff

It is discussed how the dijet azimuthal correlations in DIS and real photoproduction at HERA probe the unintegrated gluon distribution in the proton. The correlation function shows a strong dependence on kinematical variables. We discuss a…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. Szczurek

Recent results from the HERA experiment H1 on the longitudinal stucture function $F_{L}$ of the proton are presented. They include proton structure function analyses with particular emphasis on those kinematic regions which are sensitive to…

High Energy Physics - Phenomenology · Physics 2008-11-26 N. Gogitidze

In the framework of k_T-factorization QCD approach and the colour singlet model we consider J/\psi inelastic photo- and leptoproduction processes at HERA. We investigate the dependences of the single differential and double differential…

High Energy Physics - Phenomenology · Physics 2009-01-07 A. V. Lipatov , N. P. Zotov

The current uncertainty on the gluon density extracted from the global parton analysis is large in the kinematical range of small values of the Bjorken - $x$ variable and low values of the hard scale $Q^2$. An alternative to reduces this…

High Energy Physics - Phenomenology · Physics 2016-04-05 V. P. Goncalves , L. A. S. Martins , W. K. Sauter

We investigate the nucleon and pion gluon distribution functions in the framework of holographic QCD, focusing on the small Bjorken x region. Based on an approximate relation, the gluon distributions are extracted from structure functions…

High Energy Physics - Phenomenology · Physics 2020-06-24 Akira Watanabe , Takahiro Sawada , Mei Huang

We use perturbative QCD, beyond the leading $\ln Q^2$ approximation, to show how measurements of diffractive $J/\psi$ production at HERA can provide a sensitive probe of the gluon density of the proton at small values of Bjorken $x$. We…

High Energy Physics - Phenomenology · Physics 2008-02-03 M. G. Ryskin , R. G. Roberts , A. D. Martin , E. M. Levin

Measurements of the diffractive structure function, $F_2^D$, of the proton at HERA are used to extract the partonic structure of the Pomeron. Regge Factorization is tested and is found to describe well the existing data within the selected…

High Energy Physics - Phenomenology · Physics 2011-07-19 Halina Abramowicz , Michael Groys , Aharon Levy

We calculate the next-to-leading order fully unintegrated hard scattering coefficient for unpolarized gluon-induced deep inelastic scattering using the logical framework of parton correlation functions developed in previous work. In our…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ted C. Rogers

The gluon content of the proton is embodied by the unintegrated gluon distribution (UGD), which has universal validity. In literature many models of UGD have been proposed so far. The polarized $\rho$-meson leptoproduction at HERA offers a…

High Energy Physics - Phenomenology · Physics 2018-08-10 Andrèe Dafne Bolognino , Francesco Giovanni Celiberto , Dmitry Yu. Ivanov , Alessandro Papa

The longitudinal structure function in deep inelastic scattering is one of the observables from which the gluon distribution can be unfolded. Consequently, this observable can be used to constrain the QCD dynamics at small $x$. In this work…

High Energy Physics - Phenomenology · Physics 2011-09-13 V. P. Goncalves , M. V. T. Machado

We present a set of formulas to extract the gluon density from the Berger-Block-Tan form of the deep inelastic structure function F2 at small x in the leading order of perturbation theory.

High Energy Physics - Phenomenology · Physics 2017-03-08 N. Yu. Chernikova , A. V. Kotikov

We use all the available new precise data for deep inelastic and related hard scattering processes to perform NLO global parton analyses. These new data allow an improved determination of partons and, in particular, the inclusion of the…

High Energy Physics - Phenomenology · Physics 2011-03-23 A. D. Martin , R. G. Roberts , W. J. Stirling , R. S. Thorne

The longitudinal proton structure function (FL) has been measured at the HERA collider in positron-proton deep inelastic scattering collisions with the H1 and ZEUS detectors. This measurement is achieved by using multiple center-of-mass…

High Energy Physics - Experiment · Physics 2010-10-07 Jason Schwartz

We report on the extension of the data fitting considering the QCD inspired model based on the summation of gluon ladders applied to the $ep$ scattering. In lines of a two Pomeron approach, the structure function $F_2$ has a hard piece…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Lengyel , M. V. T. Machado

Measurements of Deep-Inelastic Neutral and Charged current interactions are presented in lepton proton scattering at HERA. The measurements are obtained from taken during 1996 to 1999 and consists of $30 \rm{pb^{-1}}$ of $e^+p$ and $16…

High Energy Physics - Experiment · Physics 2014-11-17 Christopher M. Cormack

We determine the infrared behaviour of the BFKL forward amplitude for gluon-gluon scattering. Our approach, based on the discrete pomeron solution, leads to an excellent description of the new combined inclusive HERA data at low values of x…

High Energy Physics - Phenomenology · Physics 2010-12-14 H. Kowalski , L. N. Lipatov , D. A. Ross , G. Watt

We compare new HERA data for the longitudinal structure function $F_{\rm L}$ with the predictions of different variants of the dipole model. In particular we show that the ratio $F_{\rm L}/F_2$ is well described by the dipole models and is…

High Energy Physics - Phenomenology · Physics 2015-10-29 Marek Niedziela , Michal Praszalowicz

Recent developments of the small $x$ CCFM evolution are described, including improvements of the splitting function. The resulting unintegrated gluon densities are used for predictions of hadronic final state measurements like jet…

High Energy Physics - Phenomenology · Physics 2011-01-25 Hannes Jung