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Related papers: Low $Q^2$ proton structure function, using gluon a…

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A measurement of the proton structure function $F_{\!2}(x,Q^2)$ is reported for momentum transfer squared $Q^2$ between 4.5 $GeV^2$ and 1600 $GeV^2$ and for Bjorken $x$ between $1.8\cdot10^{-4}$ and 0.13 using data collected by the HERA…

High Energy Physics - Experiment · Physics 2012-08-27 H1 Collaboration

Calculations are presented of the longitudinal structure function $F_L(x, Q^2)$. We use next-to-leading order expressions in QCD $({\cal{O}}(\alpha_s^2))$ plus parton densities determined previously from global fits to data on deep…

High Energy Physics - Phenomenology · Physics 2014-11-17 Edmond L. Berger , Ruibin Meng

In the semiclassical approach, inclusive and diffractive quark and gluon distributions are expressed in terms of correlation functions of Wilson loops. Each Wilson loop integrates the colour field strength in the area between the…

High Energy Physics - Phenomenology · Physics 2010-03-25 W. Buchmuller , T. Gehrmann , A. Hebecker

The parton structure of the nucleon and pion is investigated in an exploratory model that allows one to assess whether the dressing of quarks can, by itself, produce realistic gluon contributions to light-cone momentum fractions,…

Nuclear Theory · Physics 2025-05-02 Peter C. Tandy

A measurement of the derivative (d ln F_2 / d lnx)_(Q^2)= -lambda(x,Q^2) of the proton structure function F_2 is presented in the low x domain of deeply inelastic positron-proton scattering. For 5*10^(-5)<=x<=0.01 and Q^2>=1.5 GeV^2,…

High Energy Physics - Experiment · Physics 2010-03-25 H1 Collaboration , C. Adloff

We employ the maximum entropy method to extract the valence quark distributions of the neutron at a low scale, \( Q_0^2 \). At this initial scale, the neutron is defined to contain only three valence quarks, with no contributions from sea…

High Energy Physics - Phenomenology · Physics 2025-12-17 Chengdong Han , Rong Wang , Xurong Chen

The quantitative knowledge of heavy nuclei's partonic structure is currently limited to rather large values of momentum fraction $x$ -- robust experimental constraints below $x \sim 10^{-2}$ at low resolution scale $Q^2$ are particularly…

Nuclear Experiment · Physics 2017-12-13 E. C. Aschenauer , S. Fazio , M. A. C. Lamont , H. Paukkunen , Pia Zurita

We discuss the dressing of constituent quarks with a pseudoscalar meson cloud within the effective chiral quark model. SU(3) flavor symmetry breaking effects are included explicitly. Our results are compared with those of the traditional…

Nuclear Theory · Physics 2008-11-26 Antoni Szczurek , Alfons J. Buchmann , Amand Faessler

We present a complete set of formulas for longitudinal momentum distribution functions (splitting functions) of mesons in the nucleon. It can be applied in the framework of convolution formalism to the deep-inelastic structure functions…

High Energy Physics - Phenomenology · Physics 2014-11-17 H. Holtmann , A. Szczurek , J. Speth

Using a simple picture of the constituent quark as a composite system of point-like partons, we construct the parton distributions by a convolution between constituent quark momentum distributions and constituent quark structure functions.…

High Energy Physics - Phenomenology · Physics 2011-07-19 Sergio Scopetta , Vicente Vento , Marco Traini

The behavior of the gluon distribution of the proton in the low-$x$, low-$Q^2$ domain of deep inelastic electron-proton scattering (DIS) is being investigated. By considering two-gluon exchange as the dominant interaction in the low-$x$,…

High Energy Physics - Phenomenology · Physics 2026-02-24 G. R. Boroun , M. Kuroda , Dieter Schildknecht

Using constituent quark model constraints we calculate the gluon and sea-quark content of pions solely in terms of their valence density (fixed by \pi N Drell-Yan data) and the known sea and gluon distributions of the nucleon, using the…

High Energy Physics - Phenomenology · Physics 2010-04-06 M. Gluck , E. Reya , I. Schienbein

We calculate with chiral symmetry the parton contents of the proton based on a two-component wave function. The calculation results give significant sea-quark contents and, especially, the intrinsic gluon polarization produced at a more…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chung-Yi Wu

Nuclear deep inelastic structure functions F_2^A(x,Q^2) as well as parton distribution functions in a nuclei are investigated in the framework of rescaling model. Our analysis is based on analytical expressions for quark and gluon densities…

High Energy Physics - Phenomenology · Physics 2024-04-11 A. V. Kotikov , A. V. Lipatov , P. M. Zhang

Unique measurement of the proton structure function F2 in a wide two-dimensional region of x and Q**2 has been reported. The accessible kinematics covers entire resonance region up to W=2.5 GeV in the Q**2 interval from 0.1 to 4.5 GeV**2.…

High Energy Physics - Experiment · Physics 2017-08-23 M. Osipenko , G. Ricco , M. Taiuti , M. Anghinolfi , M. Battaglieri , R. De Vita , M. Ripani , the CLAS Collaboration

Study of parton distribution functions (PDFs) has led to a finer cognisance of the structure of partons in hadrons and the proton structure functions in deep inelastic scattering (DIS). PDFs are instrumental in predicting results for most…

High Energy Physics - Phenomenology · Physics 2025-10-02 Akbari Jahan , Diptimonta Neog

In this paper we study the gluon distribution functions in nucleons and pions at a low resolution $Q^2$ scale. This is an important issue since parton densities at low $Q^2$ have always been taken as an external input which is adjusted…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. R. Christiansen , J. Magnin

In this work, we investigate the constituent parton distribution functions (PDFs) of the kaon and heavy pseudoscalar mesons within the light-cone quark model. Starting from the initial scale quark and antiquark PDFs, obtained by evaluating…

High Energy Physics - Phenomenology · Physics 2026-05-19 Satyajit Puhan

The use of the differential gluon structure function of the proton ${\cal F}(x,Q^{2})$ introduced by Fadin, Kuraev and Lipatov in 1975 is called upon in many applications of small-x QCD. We report here the first determination of ${\cal…

High Energy Physics - Phenomenology · Physics 2014-11-17 I. P. Ivanov , N. N. Nikolaev