English
Related papers

Related papers: Structure Functions

200 papers

We present a first QCD analysis of next-to-next-leading-order (NNLO) contributions of the spin-dependent parton distribution functions (PPDFs) in the nucleon and their uncertainties using the Jacobi polynomial approach. Having the NNLO…

High Energy Physics - Phenomenology · Physics 2016-06-24 F. Taghavi Shahri , Hamzeh Khanpour , S. Atashbar Tehrani , Z. Alizadeh Yazdi

A new measurement of the proton structure function $F_2(x,Q^2)$ is reported for momentum transfers squared $Q^2$ between 1.5 GeV$^2$ and 5000 GeV$^2$ and for Bjorken $x$ between $3\cdot 10^{-5}$ and 0.32 using data collected by the HERA…

High Energy Physics - Experiment · Physics 2010-03-25 S. Aid , H1 Collaboration

It is shown that the CKMT model for the nucleon structure function F2, taken as the initial condition for the NLO evolution equations in perturbative QCD, provides a good description of the HERA data when presented in the form of the…

High Energy Physics - Phenomenology · Physics 2009-01-07 A. B. Kaidalov , C. Merino , D. Pertermann

We study the next-to-next-to-leading order (NNLO) evolution of flavour singlet parton densities and structure functions in massless perturbative QCD. Present information on the corresponding three-loop splitting functions is used to derive…

High Energy Physics - Phenomenology · Physics 2009-10-31 W. L. van Neerven , A. Vogt

We review recent progress in the understanding of the spin structure of the nucleon. For the free nucleon the issues addressed include the status of the Bjorken and Ellis-Jaffe sum-rules and the role of the axial anomaly. We outline recent…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. W. Thomas

We have studied the nucleon structure functions $F_{iN}^{EM} (x,Q^2);~i=1,2$, by including contributions due to the higher order perturbative QCD effect up to NNLO and the non-perturbative effects due to the kinematical and dynamical higher…

High Energy Physics - Phenomenology · Physics 2019-06-05 F. Zaidi , H. Haider , M. Sajjad Athar , S. K. Singh , I. Ruiz Simo

We re-examine the large-x neutron/proton structure function ratio extracted from the latest deuteron data, taking into account the most recent developments in the treatment of Fermi motion, binding and nucleon off-shell effects in the…

Nuclear Theory · Physics 2008-11-26 W. Melnitchouk , A. W. Thomas

The spin structure of nucleon at twist 2 and 3 levels is analyzed. The contribution of quark and gluon spins to nucleon spin are Lorentz invariant, while it is not sure for orbital angular momentum. The conserved fractional moments of…

High Energy Physics - Phenomenology · Physics 2007-05-23 O. Teryaev , B. Pire , J. Soffer

We recall the physical features of the parton distributions in the quantum statistical approach of the nucleon. Some predictions from a next-to-leading order QCD analysis are compared to recent experimental results. We also consider their…

High Energy Physics - Phenomenology · Physics 2011-07-26 Jacques Soffer

We perform the next-to-next-leading-order (NNLO) QCD global fit of PDFs using inclusive charged-lepton and neutrino DIS data down to Q = 1 GeV. We also consider the data on neutrino-nucleon dimuon production, that allows us to disentangle…

High Energy Physics - Phenomenology · Physics 2008-10-28 S. Alekhin , S. Kulagin , R. Petti

The structure of neutrons, protons, and other strongly interacting particles is now being calculated in full, unquenched lattice QCD with quark masses entering the chiral regime. This talk describes selected examples, including the nucleon…

We summarize recent results on the evolution of unpolarized parton densities and deep-inelastic structure functions in massless perturbative QCD. Due to last year's extension of the integer-moment calculations of the three-loop splitting…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. L. van Neerven , A. Vogt

We start from an MIT-bag model calculation which provides information about the constituent quark distributions in the nucleon. The constituent quarks, however, are themselves considered as complex objects whose partonic substructure is…

High Energy Physics - Phenomenology · Physics 2009-09-25 J. Keppler , H. M. Hofmann

The results of a recent next-to-leading order QCD analysis of the world data on polarized deep inelastic scattering are reported. New parameterizations are derived for the quark and gluon distributions, accounting for the massive Wilson…

High Energy Physics - Phenomenology · Physics 2015-05-20 Johannes Blümlein , Helmut Böttcher

We calculate the partonic structure of a constituent quark in the Next-to-Leading Order framework. The structure of any hadron can be obtained thereafter using a convolution method. Such a procedure is used to generate the structure…

High Energy Physics - Phenomenology · Physics 2009-11-10 F. Arash , A. N. Khorramian

A new ''$\mathtt{SK24}$'' non-singlet QCD analysis of the structure functions at the NNLO approximation is performed, utilizing the global fit of the data from various charged lepton scattering experiments. We extract the valence parton…

High Energy Physics - Phenomenology · Physics 2024-06-07 Javad Shahrzad , Ali Khorramian

The present understanding of the spin structure of the nucleon is briefly reviewed. The main focus is on parton helicity distributions, orbital angular momentum of partons as defined through generalized parton distributions, as well as…

High Energy Physics - Phenomenology · Physics 2017-08-23 A. Metz

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…

In the context of noncommutative space-time, we investigate the nucleon structure functions which plays an important role to identify the internal structure of nucleons. We use the corrected vertices and employ new vertices that appear in…

High Energy Physics - Phenomenology · Physics 2017-05-23 Ali Rafiei , Zahra Rezaei , Abolfazl Mirjalili

The transverse nucleon spin can be transferred to the quarks and gluons in several ways. In the factorizing, hard scattering processes to be considered, these are parameterized at leading twist by the transversity distribution function and…

High Energy Physics - Phenomenology · Physics 2009-11-07 Daniel Boer