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Related papers: Proton structure functions at low $x$: the Fractal…

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A determination of Parton Distribution Functions (PDFs) from a global fit to a dataset including measurements from the LHC has been performed. The determinations have been carried out according to the NNPDF methodology, leading to a fit…

High Energy Physics - Phenomenology · Physics 2014-11-04 Nathan Hartland

We present a lattice QCD calculation of the unpolarized isovector quark parton distribution function (PDF) of the proton utilizing a perturbative matching at next-to-next-to-leading-order (NNLO). The calculations are carried out using a…

High Energy Physics - Lattice · Physics 2023-05-10 Xiang Gao , Andrew D. Hanlon , Jack Holligan , Nikhil Karthik , Swagato Mukherjee , Peter Petreczky , Sergey Syritsyn , Yong Zhao

We study the relation between the quark distribution function q(x) and the fragmentation function D_q(z) based on a general form D_q(x) = C(z)z^{alpha}q(z) for valence and sea quarks. By adopting two known parametrizations of quark…

High Energy Physics - Phenomenology · Physics 2009-11-07 Bo-Qiang Ma , Ivan Schmidt , Jacques Soffer , Jian-Jun Yang

To facilitate lattice QCD calculations of nucleon structute, a set of quasi-parton distributions were recently introduced. These quasi-PDFs were shown to reduce to standard PDFs when the nucleon is boosted to high energies, $P_z\rightarrow…

High Energy Physics - Phenomenology · Physics 2016-05-24 Leonard Gamberg , Zhong-Bo Kang , Ivan Vitev , Hongxi Xing

The last two decades have seen a growing trend towards the experimental efforts at the electron-proton collider HERA in which have collected high precision data on the spectrum of leading neutron (LN) and leading-proton (LP) carrying a…

High Energy Physics - Phenomenology · Physics 2018-07-04 Samira Shoeibi , F. Taghavi-Shahri , Kurosh Javidan

We recall our recent description of quark parton densities of the proton at $Q^2=4 GeV^2$ in terms of Fermi-Dirac distributions parametrized with very few free parameters. We have also proposed some simple assumptions to relate unpolarized…

High Energy Physics - Phenomenology · Physics 2016-09-01 Claude Bourrely , Jacques Soffer

We present an updated set of {\tt SKMHS} diffractive parton distribution functions (PDFs). In addition to the diffractive deep-inelastic scattering (diffractive DIS) data sets, the recent diffractive dijet cross sections measurements by the…

High Energy Physics - Phenomenology · Physics 2023-06-14 Maral Salajegheh , Hamzeh Khanpour , Ulf-G. Meißner , Hadi Hashamipour , Maryam Soleymaninia

Determination of proton parton distribution functions is present under the dynamical parton model assumption by applying DGLAP equations with GLR-MQ-ZRS corrections. We provide two data sets, referred as IMParton16, which are from two…

High Energy Physics - Phenomenology · Physics 2017-04-03 Rong Wang , Xurong Chen

The parton distribution functions (PDFs) of the proton are one of the essential ingredients to describe physics processes at hadron colliders. The Z boson production data at the LHC have a potential to constrain PDFs, especially the gluon…

High Energy Physics - Phenomenology · Physics 2016-08-31 Rajdeep M Chatterjee , Monoranjan Guchait , Ringaile Placakyte

This review paper presents the gluon, sea, and valence quark distributions of the pseudoscalar (PS) mesons. The calculations of the parton structure of PS mesons are performed using the Bethe-Salpeter equation-Nambu--Jona-Lasinio (BSE-NJL)…

High Energy Physics - Phenomenology · Physics 2023-03-06 Parada T. P. Hutauruk , Seung-il Nam

A first measurement is reported of the longitudinal proton structure function F_L(x,Q^2) at the ep collider HERA. It is based on inclusive deep inelastic e^+p scattering cross section measurements with a positron beam energy of 27.5 GeV and…

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

We report on a measurement of the proton structure function $F_2$ in the range $3.5\times10^{-5}\leq x \leq 4\times10^{-3}$ and 1.5 ${\rm GeV^2} \leq Q^2 \leq15$ ${\rm GeV^2}$ at the $ep$ collider HERA operating at a centre-of-mass energy…

High Energy Physics - Experiment · Physics 2012-08-27 The ZEUS Collaboration

We present NNPDFpol2.0, a new set of collinear helicity parton distribution functions (PDFs) of the proton based on legacy measurements of structure functions in inclusive neutral-current longitudinally polarised deep-inelastic scattering…

We extend the MRS(A) set of parton distributions, which provides an up-to-date description of the structure of the proton probed by hard interactions, into the region of $Q^2$ below $5\ {\rm GeV}^2$. After physically-motivated…

High Energy Physics - Phenomenology · Physics 2009-10-28 AD Martin , WJ Stirling , RG Roberts

The kinematic region covered by the LHC experiments probes low values of Bjorken-$x$. At the scale relevant for $W$ and $Z$ production the central rapidity region covers $10^{-3} < x < 10^{-1}$. This means that it is the HERA data which…

High Energy Physics - Phenomenology · Physics 2015-03-17 Amanda Cooper-Sarkar

We present MAPPDFpol1.0, a new determination of the helicity-dependent parton distribution functions (PDFs) of the proton from a set of longitudinally polarised inclusive and semi-inclusive deep-inelastic scattering data. The determination…

High Energy Physics - Phenomenology · Physics 2025-04-23 MAP , Collaboration , : , Valerio Bertone , Amedeo Chiefa , Emanuele R. Nocera

We analyse recent data on the production of forward neutrons in deep inelastic scattering at HERA in the framework of a perturbative QCD description for semi-inclusive processes, which includes fracture functions. Using a model estimate for…

High Energy Physics - Phenomenology · Physics 2009-10-30 Daniel de Florian , Rodolfo Sassot

We present pion and kaon parton distribution functions from a global QCD analysis of the experimental data within the framework of dynamical parton model. We use the DGLAP equations with parton-parton recombination corrections and the…

High Energy Physics - Phenomenology · Physics 2021-06-03 Chengdong Han , Gang Xie , Rong Wang , Xurong Chen

At a low resolution scale with $Q^2={\mu}^2$ corresponding to the nucleon bound state; deep inelastic unpolarized structure functions $F_1(x,{\mu}^2)$ and $F_2(x,{\mu}^2)$ are derived with correct support using the symmetric part of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 N. Barik , R. N. Mishra

Large momentum effective field theory provides a new direction for lattice QCD calculations of hadronic structure functions, such as parton distribution functions (PDFs), meson distribution amplitudes, and so on, directly with…

High Energy Physics - Phenomenology · Physics 2018-08-03 Xiaonu Xiong , Thomas Luu , Ulf-G. Meißner