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Related papers: Parton Distributions for Low Q^2

200 papers

A simple parametrisation of H1 and ZEUS data at HERA is given for the ranges in x and Q^2 of 10^{-4} - 5.10^{-2} and 5 - 250 GeV^2, respectively. This empirical expression is based on a strikingly similar dependence of the average charged…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. De Roeck , E. A. De Wolf

We use detailed balance for a hadron composed of quark and gluon Fock states to obtain parton distributions in the proton and pion on the basis of a simple statistical model.

High Energy Physics - Phenomenology · Physics 2008-11-26 Mary Alberg , Ernest M. Henley

We summarise existing experimental and theoretical knowledge on the structure function $F_2$ in the region of low $Q^2$ and low $x$. The constraints on the behaviour of structure functions in the limit $Q^2=0$ are listed. Phenomenological…

High Energy Physics - Phenomenology · Physics 2009-09-25 Barbara Badelek , Jan Kwiecinski

Multiple parton interactions in a single proton-proton collision are expected to play an important role for many observables at LHC. To a large part their phenomenological description relies on rather simple and physically intuitive…

High Energy Physics - Phenomenology · Physics 2010-11-19 Markus Diehl

Parton distribution and correlation functions describe the relation between a hadron and the quarks and gluons (or collectively, the partons) within it, and carry rich information on hadron's partonic structure that cannot be calculated by…

High Energy Physics - Phenomenology · Physics 2020-01-08 Jian-Wei Qiu

In this talk we present the results of the investigation on the so called double parton distribution functions (dPDFs), accessible quantities in high energy proton-proton and proton nucleus collisions, in double parton scattering processes…

High Energy Physics - Phenomenology · Physics 2021-02-03 Matteo Rinaldi

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

We determine the nuclear modifications of parton distribution functions of bound protons at scales $Q^2\ge 1.69$ GeV$^2$ and momentum fractions $10^{-5}\le x\le 1$ in a global analysis which utilizes nuclear hard process data, sum rules and…

High Energy Physics - Phenomenology · Physics 2014-11-18 Kari J. Eskola , Vesa J. Kolhinen , Hannu Paukkunen , Carlos A. Salgado

Structure functions, as measured in lepton-nucleon scattering, have proven to be very useful in studying the quark dynamics within the nucleon. However, it is experimentally difficult to separately determine the longitudinal and transverse…

We discuss uncertainties in the extraction of parton distributions from global analyses of DIS and related data. We present conservative sets of partons, at both NLO and NNLO, which are stable to x,Q^2,W^2 cuts on the data. We give the…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. D. Martin , R. G. Roberts , W. J. Stirling , R. S. Thorne

This review deals with the structure of hadrons, strongly interacting many-body systems consisting of quarks and gluons. These systems have a size of about 1 fm, which shows up in scattering experiments at low momentum transfers $Q$ in the…

High Energy Physics - Phenomenology · Physics 2009-09-29 Dieter Drechsel , Thomas Walcher

In this paper we study a 1+1 dimensional relativistic parton model for the structure of baryons. The quarks and anti-quarks interact through a linear potential. We obtain an analytic formula for the isospin averaged valence quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. John , G. S. Krishnaswami , S. G. Rajeev

A new generation of parton distribution functions with increased precision and quantitative estimates of uncertainties is presented. This work significantly extends previous CTEQ and other global analyses on two fronts: (i) a full treatment…

High Energy Physics - Phenomenology · Physics 2011-07-18 J. Pumplin , D. R. Stump , J. Huston , H. L. Lai , P. Nadolsky , W. K. Tung

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

We use an s-channel picture of hard hadronic collisions to investigate the parton distribution function for quarks at small momentum fraction x, which corresponds to very high energy scattering. We study the renormalized quark distribution…

High Energy Physics - Phenomenology · Physics 2008-11-26 F. Hautmann , D. E. Soper

We consider the pion structure in the region of low and moderately high momentum transfers: at low $Q^2$, the pion is treated as a composite system of constituent quarks; at moderately high momentum transfers, $Q^2=10\div25\;GeV^2$, the…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Anisovich , D. Melikhov , V. Nikonov

We present parton distribution functions which include a quantitative estimate of its uncertainties. The parton distribution functions are optimized with respect to deep inelastic proton data, expressing the uncertainties as a density…

High Energy Physics - Phenomenology · Physics 2007-05-23 Walter T. Giele , Stephane A. Keller , David A. Kosower

We explore the physics of the parton-hadron duality in the nucleon structure functions appearing in lepton-nucleon scattering. We stress that the duality allows one to extract the higher-twist matrix elements from data in the resonance…

High Energy Physics - Phenomenology · Physics 2009-10-28 Xiangdong Ji , Peter Unrau

We extract the ratio of the down (d) and up (u) parton distribution functions (PDF's) from the ratio of NMC deuteron and proton structure function F_2(d)/F_2(p), using corrections for nuclear binding effects in the deuteron, which are…

High Energy Physics - Phenomenology · Physics 2007-05-23 U. K. Yang , A. Bodek

We present a calculation of the reduced cross section in momentum-space approach utilizing the Block-Durand-Ha (BDH) parameterization of the proton structure function $F_{2}(x,Q^2)$ and the leading-order (LO) longitudinal structure function…

High Energy Physics - Phenomenology · Physics 2025-02-12 G. R. Boroun , Phuoc Ha