English
Related papers

Related papers: NLO prescription for unintegrated parton distribut…

200 papers

We present an introductory discussion of deep-inelastic lepton-proton scattering as a means to probe the substructure of the proton. A resume of QCD is given, emphasizing the running of the coupling constant and the DGLAP evolution…

High Energy Physics - Phenomenology · Physics 2010-03-25 Alan D. Martin

We report on recent determinations of NNLO parton distributions and of $\alpha_s(M_Z)$ based on the world deep-inelastic data, supplemented by collider data. Some applications are discussed for semi-inclusive processes at the LHC.

High Energy Physics - Phenomenology · Physics 2013-03-19 S. Alekhin , J. Blümlein , S. Moch

To overcome the complexity of generalized two hard scale ($k_t$,$\mu$) evolution equation, well known as the $Ciafaloni$, $Catani$, $Fiorani$ and $Marchsini$ ($CCFM$) evolution equations, and calculate the unintegrated parton distribution…

Nuclear Theory · Physics 2011-01-13 H Hosseinkhani , M Modarres

We present the construction of unintegrated double parton distribution functions which include dependence on transverse momenta of partons. We extend the formulation which was used to obtain the single unintegrated parton distributions from…

High Energy Physics - Phenomenology · Physics 2017-03-08 K. Golec-Biernat , A. M. Stasto

Collinear and transverse momentum dependent (TMD) parton densities are obtained from fits to precision measurements of deep inelastic scattering (DIS) cross sections at HERA. The parton densities are evolved by DGLAP evolution with…

High Energy Physics - Phenomenology · Physics 2019-04-17 A. Bermudez Martinez , P. Connor , F. Hautmann , H. Jung , A. Lelek , V. Radescu , R. Zlebcik

A new NLO DGLAP QCD fit to recent inclusive diffractive DIS data from the H1 collaboration is presented. Diffractive parton distributions are extracted, including their experimental and theoretical uncertainties. The parton distributions…

High Energy Physics - Experiment · Physics 2014-11-17 Frank-Peter Schilling

We have used QCD and polarized deep-inelastic scattering data to construct x-dependent polarized parton distributions. These flavor dependent distributions evolve under the NLO DGLAP equations, satisfy positivity constraints and agree well…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gordon P. Ramsey

We describe how unintegrated parton distributions can be calculated from conventional integrated distributions. We extend and improve the 'last-step' evolution approach, and explain why doubly-unintegrated parton distributions are…

High Energy Physics - Phenomenology · Physics 2014-11-17 G. Watt , A. D. Martin , M. G. Ryskin

In this paper, we discuss the algorithms used in the LO evolution program for nondiagonal parton distributions in the DGLAP region and discuss the stability of the code. Furthermore, we demonstrate that we can reproduce the case of the LO…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Freund , Vadim Guzey

We calculate the cross section for the inclusive production of single hadrons with finite transverse momenta in deep-inelastic scattering at next-to-leading order (NLO), i.e. through O(alpha_s^2), in the parton model of QCD endowed with…

High Energy Physics - Phenomenology · Physics 2010-11-05 B. A. Kniehl , G. Kramer , M. Maniatis

We present numerical solutions of the $Q^2$ evolution equations at next-to-leading order (NLO) for unpolarized and polarized parton distributions, in both the flavor non-singlet and singlet channels. The numerical method is based on a…

High Energy Physics - Phenomenology · Physics 2009-10-28 T. Weigl , W. Melnitchouk

In a series of papers, we have investigated the compatibility of the $Kimber$-$Martin$-$Ryskin$ ($KMR$) and $Martin$-$Ryskin$-$Watt$ ($MRW$) $unintegrated$ parton distribution functions ($UPDF$) as well as the description of the…

High Energy Physics - Phenomenology · Physics 2016-11-02 M. Modarres , M. R. Masouminia , R. Aminzadeh-Nik , H. Hosseinkhani , N. Olanj

We present a technique for implementing in a fast way, and without any approximations, higher-order calculations of partonic cross sections into global analyses of parton distribution functions. The approach, which is set up in…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Stratmann , W. Vogelsang

We present the first calculation of a fully-unintegrated parton distribution (beam function) at next-to-next-to-leading order (NNLO). We obtain the fully-differential beam function for quark-initiated processes by matching it onto standard…

High Energy Physics - Phenomenology · Physics 2015-01-05 Jonathan R. Gaunt , Maximilian Stahlhofen

Sufficiently inclusive processes, like the deep inelastic scattering (DIS), are described in terms of scale-dependent parton distributions, which correspond to the density of partons with a given longitudinal momentum fraction, integrated…

High Energy Physics - Phenomenology · Physics 2019-12-25 Francesco Giovanni Celiberto

The Parton-Branching Method (PB) facilitates the determination of Transverse Momentum Dependent (TMD) parton densities across a wide \kt\ range, spanning small to large transverse momentum scales. In the small $k_T$ region, both intrinsic…

High Energy Physics - Phenomenology · Physics 2024-02-27 S. Taheri Monfared

We present a determination of the parton distributions of the nucleon from a global set of hard scattering data using the NNPDF methodology: NNPDF2.0. Experimental data include deep-inelastic scattering with the combined HERA-I dataset,…

High Energy Physics - Phenomenology · Physics 2014-11-20 Richard D. Ball , Luigi Del Debbio , Stefano Forte , Alberto Guffanti , Jose I. Latorre , Juan Rojo , Maria Ubiali

A new type of parametrization for parton distribution functions in a proton, based on their $Q^2$-evolution at large and small $x$ values, is constructed. In our analysis, the valence and nonsinglet parts obey the Gross-Llewellyn-Smith and…

High Energy Physics - Phenomenology · Physics 2022-11-01 N. A. Abdulov , A. V. Kotikov , A. V. Lipatov

We present a first calculation of the generalized parton distributions of the photon(both polarized and unpolarized) using overlaps of light-front wave functions at leading order in \alpha and zeroth order in \alpha_s; for non-zero…

High Energy Physics - Phenomenology · Physics 2015-05-28 A. Mukherjee , S. Nair

We use the recent estimates of NNLO splitting functions, made by van Neerven and Vogt, to perform exploratory fits to deep inelastic and related hard scattering data. We investigate the hierarchy of parton distributions obtained at LO, NLO…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. D. Martin , R. G. Roberts , W. J. Stirling , R. S. Thorne