Eur. Phys. J. C (2016) 76: 471
https://doi.org/10.1140/epjc/s10052-016-4285-4

Regular Article - Experimental Physics

A critical appraisal and evaluation of modern PDFs

¹ Hampton University, Hampton, VA, 23668, USA
² Jefferson Lab, Newport News, VA, 23606, USA
³ II. Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
⁴ Institute for High Energy Physics, 142281, Protvino, Moscow region, Russia
⁵ Deutsches Elektronensynchrotron DESY, Platanenallee 6, 15738, Zeuthen, Germany
⁶ Deutsches Elektronensynchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany
⁷ Florida State University, Tallahassee, FL, 32306, USA
⁸ Institut für Physik, Technische Universität Dortmund, 44221, Dortmund, Germany
⁹ Department of Mathematical Sciences, University of Liverpool, Liverpool, L69 3BX, UK

^* e-mail: sven-olaf.moch@desy.de

Received: 5 April 2016
Accepted: 26 July 2016
Published online: 23 August 2016

Abstract

We review the present status of the determination of parton distribution functions (PDFs) in the light of the precision requirements for the LHC in Run 2 and other future hadron colliders. We provide brief reviews of all currently available PDF sets and use them to compute cross sections for a number of benchmark processes, including Higgs boson production in gluon–gluon fusion at the LHC. We show that the differences in the predictions obtained with the various PDFs are due to particular theory assumptions made in the fits of those PDFs. We discuss PDF uncertainties in the kinematic region covered by the LHC and on averaging procedures for PDFs, such as advocated by the PDF4LHC15 sets, and provide recommendations for the usage of PDF sets for theory predictions at the LHC.