English
Related papers

Related papers: Parton Distributions for Low Q^2

200 papers

We investigate the parton distribution functions (PDFs) of the pion and kaon from the eigenstates of a light-front effective Hamiltonian in the constituent quark-antiquark representation suitable for low-momentum scale applications. By…

High Energy Physics - Phenomenology · Physics 2020-09-07 Jiangshan Lan , Chandan Mondal , Shaoyang Jia , Xingbo Zhao , James P. Vary

We calculate the lowest even isovector moment of the $F_2$ structure function in $2+1$-flavour lattice QCD with varying quark masses corresponding to $m_\pi \approx [410, 360, 300] \; {\rm MeV}$, at a fixed volume of $V = 48^3 \times 96$…

High Energy Physics - Lattice · Physics 2025-05-08 K. U. Can , R. Horsley , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

We present results on two-parton densities in coordinate space, which capture a fuller dynamical picture of the proton's internal structure, including information on the relative position between quarks and gluons in the transverse plane.…

High Energy Physics - Phenomenology · Physics 2024-05-10 Zaki Panjsheeri , Joshua Bautista , Simonetta Liuti

We describe the architecture and functionalities of a C++ software framework, coined PARTONS, dedicated to the phenomenology of Generalized Parton Distributions. These distributions describe the three-dimensional structure of hadrons in…

High Energy Physics - Phenomenology · Physics 2018-04-04 B. Berthou , D. Binosi , N. Chouika , L. Colaneri , M. Guidal , C. Mezrag , H. Moutarde , J. Rodríguez-Quintero , F. Sabatié , P. Sznajder , J. Wagner

The proton diffractive structure function $F_2^{D(3)}$ measured in the H1 and ZEUS experiments at HERA is analyzed in terms of both Regge phenomenology and perturbative QCD evolution. A new method determines the values of the Regge…

High Energy Physics - Phenomenology · Physics 2010-03-25 C. Royon , L. Schoeffel , J. Bartels , H. Jung , R. Peschanski

A method is described for calculating the Generalized Parton Distributions (GPDs) of spin 1/2 hadrons made of composite constituents, in an Impulse Approximation framework. GPDs are obtained from the convolution between the light cone…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sergio Scopetta

A combination of the reduced $e^{\pm}p$ cross section, previously measured by H1 and ZEUS, has been performed and leads to well constrained QCD fits of the parton densities in the proton. These results, as well as the high-$Q^2$ neutral…

High Energy Physics - Experiment · Physics 2019-08-14 Michal Wlasenko

This work presents the first calculation in lattice QCD of three moments of spin-averaged and spin-polarized generalized parton distributions in the proton. It is shown that the slope of the associated generalized form factors decreases…

High Energy Physics - Lattice · Physics 2012-08-27 LHPC , SESAM Collaborations , : , Ph. Hagler , J. W. Negele , D. B. Renner , W. Schroers , Th. Lippert , K. Schilling

I present a brief summary of the most important updates in the MRST determinations of the NLO and NNLO parton distributions. I concentrate on uncertainties due to input assumptions and possible theoretical corrections, particularly isospin…

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

Parton distributions in the virtual photon target are investigated in perturbative QCD up to the next-to-next-to-leading order (NNLO). In the case $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$) is the mass squared of the probe (target)…

High Energy Physics - Phenomenology · Physics 2009-08-05 Takahiro Ueda , Ken Sasaki , Tsuneo Uematsu

A physical model is presented for the non-perturbative parton distributions in the nucleon. This is based on quantum fluctuations of the nucleon into baryon-meson pairs convoluted with Gaussian momentum distributions of partons in hadrons.…

High Energy Physics - Phenomenology · Physics 2019-08-14 Andreas Ekstedt , Hazhar Ghaderi , Gunnar Ingelman , Stefan Leupold

We present a set of formulae to extract the gluon distribution function from the deep inelastic structure function F$_2$ and its derivative dF$_2$/dlnQ$^2$ at small x in the leading and next-to-leading order of perturbation theory. The…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. V. Kotikov , G. Parente

Power-suppressed corrections to parton evolution may affect the theoretical accuracy of current determinations of parton distributions. We study the role of multigluon-exchange terms in the extraction of the gluon distribution for the Large…

High Energy Physics - Phenomenology · Physics 2008-11-26 F. Hautmann

The internal structure of the lowest-lying pseudo-scalar mesons with heavy-light quark content is thoroughly studied using an algebraic model that has been successfully applied to similar physical observables of pseudoscalar and vector…

High Energy Physics - Phenomenology · Physics 2024-10-18 B. Almeida-Zamora , J. J. Cobos-Martínez , A. Bashir , K. Raya , J. Rodríguez-Quintero , J. Segovia

We present preliminary results on simple modifications and corrections to GRV94 leading order parton distribution functions such that they can be used to model electron,muon and neutrino deep-inelastic scattering cross sections at low…

High Energy Physics - Experiment · Physics 2009-11-07 A. Bodek , U. K. Yang

Recent measurements for F_2(x,Q^2) have been analyzed in terms of the `dynamical' and `standard' parton model approach at NLO and NNLO of perturbative QCD. Having fixed the relevant NLO and NNLO parton distributions, the implications and…

High Energy Physics - Phenomenology · Physics 2015-05-13 Cristian Pisano

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

The generalized parton distributions and the generalized distribution amplitudes give access to a deeper understanding of the quark and gluon content of hadrons. In this short review, we select some new developments of their interesting…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. Pire

This study focuses on the presence of (multi)fractal structures in confined hadronic matter through the momentum distributions of mesons produced in proton-proton collisions between 23 GeV and 63 GeV. The analysis demonstrates that the…

High Energy Physics - Theory · Physics 2023-09-01 Rafael P. Baptista , Lucas Q. Rocha , D. P. Menezes , Luis A. Trevisan , Constantino Tsallis , Airton Deppman

Analyses of structure functions (SFs) from neutrino and muon deep inelastic scattering data have shown discrepancies in F2 for x < 0.1. A new SF analysis of the CCFR collaboration data examining regions in x down to x=.0015 and 0.4 < Q^2 <…

‹ Prev 1 8 9 10 Next ›