English
Related papers

Related papers: The HOPPET NNLO parton evolution package

200 papers

We report the parton distribution functions (PDFs) determined from the NNLO QCD analysis of the world inclusive DIS data with account of the precise NNLO QCD corrections to the evolution equations kernel. The value of strong coupling…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Alekhin

In this article we present a review of the structure of the proton and the current status of our knowledge of the parton distribution functions (PDFs). The lepton-nucleon scattering experiments which provide the main constraints in PDF…

High Energy Physics - Experiment · Physics 2013-03-20 Emmanuelle Perez , Eram Rizvi

We derive evolution equations for the truncated Mellin moments of the parton distributions. We find that the equations have the same form as those for the partons themselves. The modified splitting function for n-th moment $P'(n,x)$ is…

High Energy Physics - Phenomenology · Physics 2010-03-25 D. Kotlorz , A. Kotlorz

We summarize recent progress toward the next generation of CTEQ-TEA parton distribution functions, CT25, based on a global NNLO analysis that incorporates a significant sample of newly included LHC data. We present a baseline fit within the…

High Energy Physics - Phenomenology · Physics 2025-12-30 A. Ablat , A. Courtoy , S. Dulat , Y. Fu , M. Guzzi , T. J. Hobbs , J. Huston , K. Mohan , P. Nadolsky , M. Ponce-Chavez , D. Stump , K. Xie , C. -P. Yuan

We compare predictions for high energy neutrino and anti-neutrino deep inelastic scattering cross-sections within the conventional DGLAP formalism of next-to-leading order QCD, using the latest parton distribution functions such as CT10,…

High Energy Physics - Phenomenology · Physics 2015-05-30 Amanda Cooper-Sarkar , Philipp Mertsch , Subir Sarkar

A new code for the scale evolution of modified-minimal-subtraction-scheme parton densities is described. Through next-to-leading order the program uses exact splitting functions. In next-to-next-to-leading order approximate splitting…

High Energy Physics - Phenomenology · Physics 2011-01-25 A. Chuvakin , J. Smith

The nuclear parton distribution functions (nPDFs) of gluons are known to be difficult to determine with fits of deep inelastic scattering (DIS) and Drell-Yan (DY) data alone. Therefore, the nCTEQ15 analysis of nuclear PDFs added inclusive…

High Energy Physics - Phenomenology · Physics 2021-08-02 P. Duwentäster , L. A. Husová , T. Ježo , M. Klasen , K. Kovařík , A. Kusina , K. F. Muzakka , F. I. Olness , I. Schienbein , J. Y. Yu

Using parton density functions (PDFs) with threshold-resummation improvement, we consistently calculate higgsino/gaugino and slepton pair production at next-to-leading order and next-to-leading logarithmic accuracy at the LHC. The smaller…

High Energy Physics - Phenomenology · Physics 2019-09-16 J. Fiaschi , M. Klasen

We present a new prescription to account for heavy quark mass effects in the determination of parton distribution functions (PDFs) based on the FONLL scheme. Our prescription makes explicit use of the freedom to choose the number of active…

High Energy Physics - Phenomenology · Physics 2024-10-04 Andrea Barontini , Alessandro Candido , Felix Hekhorn , Giacomo Magni , Roy Stegeman

We present an updated determination of nuclear parton distributions (nPDFs) from a global NLO QCD analysis of hard processes in fixed-target lepton-nucleus and proton-nucleus together with collider proton-nucleus experiments. In addition to…

High Energy Physics - Phenomenology · Physics 2022-05-27 Rabah Abdul Khalek , Rhorry Gauld , Tommaso Giani , Emanuele R. Nocera , Tanjona R. Rabemananjara , Juan Rojo

The unified description of fragmentation function evolution from large to small x which was developed for the vacuum in previous publications is now generalized to the medium, and is studied for the case in which the complete contribution…

High Energy Physics - Phenomenology · Physics 2010-01-05 S. Albino , B. A. Kniehl , R. Perez-Ramos

We calculate the electron structure functions, aka parton distribution functions (PDFs), to NNLO in QED. The calculation is based on the definition of the PDFs in terms of operator matrix elements in soft collinear effective theory (SCET)…

High Energy Physics - Phenomenology · Physics 2025-12-01 Maximilian Stahlhofen

The Fortran LHAPDF library has been a long-term workhorse in particle physics, providing standardised access to parton density functions for experimental and phenomenological purposes alike, following on from the venerable PDFLIB package.…

High Energy Physics - Phenomenology · Physics 2015-06-23 Andy Buckley , James Ferrando , Stephen Lloyd , Karl Nordstrom , Ben Page , Martin Ruefenacht , Marek Schoenherr , Graeme Watt

We explain particular, unique, approximate solutions of the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations and also solutions of DGLAP evolution equations by using regge behaviour of structure functions and method of…

High Energy Physics - Phenomenology · Physics 2010-05-07 R. Rajkhowa

We propose the formulation of a dihadron fragmentation function in terms of parton matrix elements. Under the collinear factorization approximation and facilitated by the cut-vertex technique, the two hadron inclusive cross section at…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. Majumder

We analize the use of algorithms based in x-space for the solution of renormalization group equations of DGLAP-type and test their consistency by studying bounds among partons distributions - in our specific case Soffer's inequality and the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Alessandro Cafarella , Claudio Coriano' , Marco Guzzi

I present a determination of longitudinally-polarized parton distribution functions of the proton from inclusive deep-inelastic scattering data: NNPDFpol1.0+. This determination, based on the NNPDF methodology, upgrades a previous analysis,…

High Energy Physics - Phenomenology · Physics 2016-02-17 Emanuele R. Nocera

We review the current state of the art in the determination of the parton substructure of the nucleon, as expressed in terms of parton distribution functions (PDFs), and probed in high-energy lepton-hadron and hadron-hadron collisions, and…

High Energy Physics - Phenomenology · Physics 2013-10-23 Stefano Forte , Graeme Watt

Fitting PDFs requires the integration of a broad range of datasets, both from data and theory side, into a unique framework. While for data the integration mainly consists in the standardization of the data format, for the theory…

High Energy Physics - Phenomenology · Physics 2022-11-22 Andrea Barontini , Alessandro Candido , Juan Cruz-Martinez , Felix Hekhorn , Giacomo Magni , Christopher Schwan

The photon parton distribution function (PDF) of the proton is crucial for precise comparisons of LHC cross sections with theoretical predictions. However, it was previously affected by very large uncertainties of around ${\cal O}(100\%)$…

High Energy Physics - Phenomenology · Physics 2024-08-26 Aneesh Manohar , Paolo Nason , Gavin Salam , Giulia Zanderighi