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Related papers: Parton Distribution Functions in the Schwinger Mod…

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We study the leading-twist quasi parton distribution function (quasi-PDF) and quasi generalize parton distribution (quasi-GPD) of the pion meson by using a spectator model. We consider the case the quasi functions are defined via inserting…

High Energy Physics - Phenomenology · Physics 2020-07-01 Zhi-Lei Ma , Jia-Qing Zhu , Zhun Lu

Following previous works on that topic, we consider Euclidean hadronic matrix elements in position space of two spatially separated local currents on the lattice, in order to extract the $x$ dependence of parton distribution functions…

High Energy Physics - Lattice · Physics 2024-10-11 Christian Zimmermann , Andreas Schäfer

Twist-3 collinear parton distribution functions (PDFs) are matrix elements of quark-gluon-quark or three-gluons light-cone operators. They depend on three momentum fraction variables, which are restricted to a hexagon region, and the…

High Energy Physics - Phenomenology · Physics 2024-07-10 Simone Rodini , Lorenzo Rossi , Alexey Vladimirov

Generalized Parton Distribution functions (GPDs) are off-diagonal light-cone matrix elements that encode the internal structure of hadrons in terms of quark and gluon degrees of freedom. In this work, we present the first nonperturbative…

High Energy Physics - Lattice · Physics 2025-11-25 Sebastian Grieninger , Jake Montgomery , Felix Ringer , Ismail Zahed

The parton distribution functions (PDFs) provide process-independent information about the quarks and gluons inside hadrons. Although the gluon PDF can be obtained from a global fit to experimental data, it is not constrained well in the…

High Energy Physics - Lattice · Physics 2021-06-09 Zhouyou Fan , Rui Zhang , Huey-Wen Lin

Using realistic quark propagators and meson Bethe-Salpeter amplitudes based on the Dyson-Schwinger equations, we calculate the pion and kaon's valence parton distribution functions (PDF) through the modified impulse approximation. The PDFs…

Nuclear Theory · Physics 2018-10-03 Chao Shi , Cedric Mezrag , Hong-shi Zong

In this paper, using the stochastic modeling of the non-equilibrium statistical mechanics in the momentum space, the evolution equations of the parton distribution functions (PDF) usually used in the hadrons phenomenology are generated.…

High Energy Physics - Phenomenology · Physics 2021-08-04 N. Olanj , E. Moradi , M. Modarres

We present an alternative algorithm to global fitting procedures to construct Parton Distribution Functions (PDFs) parametrizations. The proposed algorithm uses Self-Organizing Maps (SOMs) which at variance with the standard Neural…

High Energy Physics - Phenomenology · Physics 2017-08-23 H. Honkanen , S. Liuti , Y. C. Loitiere , D. Brogan , P. Reynolds

We derive a factorization theorem for Drell-Yan process at low q_T using effective field theory methods. In this theorem all the obtained quantities are gauge invariant and the special role of the soft function--and its subtraction…

High Energy Physics - Phenomenology · Physics 2015-06-03 Miguel G. Echevarria , Ahmad Idilbi , Ignazio Scimemi

The detailed comprehension of momentum fraction and energy dependence of proton structure functions is among the major difficulties in high-energy physics. Perturbative quantum chromodynamics (QCD) plays as an extensive foundation for…

High Energy Physics - Phenomenology · Physics 2025-09-25 Akbari Jahan , Diptimonta Neog

We present a new regression model for the determination of parton distribution functions (PDF) using techniques inspired from deep learning projects. In the context of the NNPDF methodology, we implement a new efficient computing framework…

High Energy Physics - Phenomenology · Physics 2019-09-04 Stefano Carrazza , Juan Cruz-Martinez

The parton distributions functions (PDFs) derived from the NNLO QCD analysis of existing light-targets deep-inelastic-scattering data are presented. The NLO and NNLO PDFs are compared in order to analyze perturbative stability of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Alekhin

In a spin-1 hadron, tensor-polarized parton distribution functions (PDFs) exist. The twist-2 function is $f_{1LL}$ and a twist-3 one is $f_{LT}$. Because an experiment is under preparation at the Thomas Jefferson National Accelerator…

High Energy Physics - Phenomenology · Physics 2026-05-04 S. Kumano , Kenshi Kuroki

Parton branching methods underlie the Monte Carlo (MC) generators, being therefore of key importance for obtaining high energy physics predictions. We construct a new parton branching algorithm which for the first time incorporates the…

High Energy Physics - Phenomenology · Physics 2023-01-02 Aleksandra Lelek

An important limitation in current fits of parton distribution functions (PDFs) is that PDF uncertainties do not include any source of theoretical uncertainty. Here we present a general method for incorporating theoretical uncertainties…

High Energy Physics - Phenomenology · Physics 2018-10-05 R. L. Pearson , C. Voisey

In global PDF analyses, parton distribution functions (PDFs) are parametrised at a fixed input scale $Q_0$ and evolved to higher scales using the DGLAP equations. Since QCD evolution is fully determined within perturbation theory, the…

High Energy Physics - Phenomenology · Physics 2025-11-13 Ivan A. Godino , Eva D. Z. Groenendijk , Tanjona R. Rabemananjara

We present the software framework underlying the NNPDF4.0 global determination of parton distribution functions (PDFs). The code is released under an open source licence and is accompanied by extensive documentation and examples. The code…

We present the first open-source analysis of parton distribution functions (PDFs) of charged pions using xFitter, an open-source QCD fit framework to facilitate PDF extraction and analyses. Our calculations are implemented at…

It is anticipated that hard double parton scatterings will occur frequently in the collisions of the LHC, producing interesting signals and significant backgrounds to certain single scattering processes. For double scattering processes in…

High Energy Physics - Phenomenology · Physics 2015-03-13 Jonathan R. Gaunt , W. James Stirling

We show that any determination of the strong coupling $\alpha_s$ from a process which depends on parton distributions, such as hadronic processes or deep-inelastic scattering, generally does not lead to a correct result unless the parton…

High Energy Physics - Phenomenology · Physics 2020-03-18 Stefano Forte , Zahari Kassabov