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Related papers: Theoretical description of the HERA data on $F_2$

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Recent data on the proton F_2 structure function in the resonance region suggest that local quark-hadron duality works remarkably well for each of the low-lying resonances, including the elastic, to rather low values of Q^2. We derive…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Melnitchouk

We present a determination of the parton distribution functions of the proton in which NLO and NNLO fixed-order calculations are supplemented by NLLx small-x resummation. Deep inelastic structure functions are computed consistently at…

High Energy Physics - Phenomenology · Physics 2018-05-09 Richard D. Ball , Valerio Bertone , Marco Bonvini , Simone Marzani , Juan Rojo , Luca Rottoli

Measurements of the diffractive structure function $F_2^{D(3)}(x_{\PO}, \beta, Q^2)$, describing the process $ep \to eXY$, are presented in the two kinematic regions $0.4 \leq Q^2 \leq 5$, ${\rm GeV}^2$, $0.001 \leq \beta \leq 0.65$, and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Christophe Royon

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

We introduce a new parametrization for the parton distribution functions (PDFs) designed to be flexible in the small-x region. We implement it in the xFitter open-source PDF fitting tool, and compare it to the default xFitter…

High Energy Physics - Phenomenology · Physics 2019-10-25 Marco Bonvini , Francesco Giuli

An explicit model for the proton structure function interpolating between low- (VMD and Regge behavior)and high-$Q^2$ (GLAP evolution) is suggested. The model is fitted to the experimental data in a wide range of the kinematical variables…

High Energy Physics - Phenomenology · Physics 2014-11-17 P. Desgrolard , L. Jenkovszky , F. Paccanoni

QED Compton scattering at HERA is discussed in terms of the information it may reveal on the proton structure at low momentum transfers Q2. Detailed Monte Carlo studies are performed which show that the analysis of inelastic QED Compton…

High Energy Physics - Phenomenology · Physics 2011-07-19 V. Lendermann , H. -C. Schultz-Coulon , D. Wegener

We argue that the use of the universal unintegrated gluon distribution and the $k_T$ (or high energy) factorization theorem provides the natural framework for describing observables at small x. We introduce a coupled pair of evolution…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Kwiecinski , A. D. Martin , A. M. Stasto

The first measurements of the diffractive structure function $F_2^{D(3)}$ at HERA are discussed. A factorisable interpretation in which a partonic structure is assigned to the pomeron is investigated through QCD analyses in which both the…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Golec-Biernat , J. P. Phillips

We present non-linear corrections (NLC) to the distribution functions at low values of $x$ and $Q^{2}$ using the parametrization $F_{2}(x,Q^{2})$ and $F_{L}(x,Q^{2})$. We use a direct method to extract non-linear corrections to the ratio of…

High Energy Physics - Phenomenology · Physics 2021-10-11 G. R. Boroun , B. Rezaei

A new structure function analysis of CCFR deep inelastic nu-N and nubar-N scattering data is presented for previously unexplored kinematic regions down to Bjorken x=0.0045 and Q^2=0.3 GeV^2. Comparisons to charged lepton scattering data…

High Energy Physics - Experiment · Physics 2007-05-23 NuTeV Collaboration , B. T. Fleming

We suggest a modified form of a unitarized BFKL equation imposing the so-called kinematic constraint on the gluon evolution in multi-Regge kinematics. The underlying nonlinear effects on the gluon evolution are investigated by solving the…

High Energy Physics - Phenomenology · Physics 2019-06-14 P. Phukan , M. Lalung , J. K. Sarma

A model for the longitudinal structure function $F_L$ at low $x$ and low $Q^2$ is presented, which includes the kinematical constraint $F_L \sim Q^4$ as $Q^2 \rightarrow 0$. It is based on the photon-gluon fusion mechanism suitably…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Badelek , J. Kwiecinski , A. Stasto

We examine HERA data with a view of determining whether unique signs of saturation can be identified. Concentrating on two channels the logarithmic slope of $F_{2}$, and the production of $J/\Psi$, which are sensitive to the behaviour of…

High Energy Physics - Phenomenology · Physics 2017-08-23 Errol Gotsman

Several topics from the wide field of QCD studies in Deep-inelastic $ep$ Scattering at HERA are addressed. They include QCD analyses of the inclusive cross section with the determination of $\alpha_s$ and the proton gluon density from the…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Olsson

The parton momentum densities in the proton are obtained from a NLO QCD analysis of structure functions measured by HERA and fixed target experiments. The uncertainties in these parton densities, the structure functions and related cross…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Botje

The results of LO {\it Fixed point} QCD (FP-QCD) analysis of the CCFR data for the nucleon structure function $~xF_3(x,Q^2)~$ are presented. The predictions of FP-QCD, in which the Callan-Symanzik $~\beta~$ function admits a {\it second…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. V. Sidorov , D. B. Stamenov

Experimental form factors of the hydrogen and helium isotopes, extracted from an up-to-date global analysis of cross sections and polarization observables measured in elastic electron scattering from these systems, are compared to…

The latest structure function results, as presented at the ICHEP98 conference, are reviewed. A brief introduction to the formalism and the status of global analyses of parton distributions is given. The review focuses on three experimental…

High Energy Physics - Experiment · Physics 2007-05-23 A. T. Doyle

We study the contribution of the truncated BFKL series to the electroproduction process showing that a reliable description is obtained taking into account two orders in perturbation theory. Using the recent F2 logarithmic slope data as a…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. B. Gay Ducati , M. V. T. Machado