Specialized minimal PDFs for optimized LHC calculations

The European Physical Journal C

Juan Rojo¹  Stefano Forte²  Zahari Kassabov³  Stefano Carrazza⁴ 

[1] Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, OX1 3NP, Oxford, UK;TIF Lab, Dipartimento di Fisica, Università di Milano, Via Celoria 16, 20133, Milan, Italy;Sezione di Milano, INFN, Via Celoria 16, 20133, Milan, Italy;TIF Lab, Dipartimento di Fisica, Università di Milano, Via Celoria 16, 20133, Milan, Italy;Sezione di Milano, INFN, Via Celoria 16, 20133, Milan, Italy;Dipartimento di Fisica, Università di Torino, Via Pietro Giuria 1, 10125, Turin, Italy;Sezione di Torino, INFN, Via Pietro Giuria 1, 10125, Turin, Italy;TIF Lab, Dipartimento di Fisica, Università di Milano, Via Celoria 16, 20133, Milan, Italy;Sezione di Milano, INFN, Via Celoria 16, 20133, Milan, Italy;Theory Department, CERN, 1211, Geneva, Switzerland;

关键词: Higgs Production;    Gluon Fusion;    Input Cross Section;    Total Inclusive Cross Section;    Principal Matrix;   

DOI  :  10.1140/epjc/s10052-016-4042-8

来源: Springer

【 摘 要 】

We present a methodology for the construction of parton distribution functions (PDFs) designed to provide an accurate representation of PDF uncertainties for specific processes or classes of processes with a minimal number of PDF error sets: specialized minimal PDF sets, or SM-PDFs. We construct these SM-PDFs in such a way that sets corresponding to different input processes can be combined without losing information, specifically as regards their correlations, and that they are robust upon smooth variations of the kinematic cuts. The proposed strategy never discards information, so that the SM-PDF sets can be enlarged by the addition of new processes, until the prior PDF set is eventually recovered for a large enough set of processes. We illustrate the method by producing SM-PDFs tailored to Higgs, top-quark pair, and electroweak gauge boson physics, and we determine that, when the PDF4LHC15 combined set is used as the prior, around 11, 4, and 11 Hessian eigenvectors, respectively, are enough to fully describe the corresponding processes.

【 授权许可】

CC BY