2011/03/31 by Simone Lionetti, Richard D. Ball, Valerio Bertone +9 · 1 citation
Physics and Astronomy · #Algorithm #Computer science #Deep inelastic scattering #HERA #High-Energy Particle Collisions Research #Inelastic scattering #Jet (fluid) #Optics #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Scattering #Thermodynamics #hep-ph
paper · pdf · doi:10.1016/j.physletb.2011.05.071
13 pages, 9 figures; final version to be published in Phys. Lett. B. Tolerance analysis for individual experiments (figs.6, 7 and tab.3) and fits with increased numbers of replicas (tab 1, 2) added. Many further small corrections
arxiv created 2011/05/31 · openalex publication_date 2011/06/19 · arxiv updated 2015/05/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We determine the strong coupling alphas from a next-to-leading order analysis of processes used for the NNPDF2.1 parton determination, which includes data from neutral and charged current deep-inelastic scattering, Drell-Yan and inclusive jet production. We find alphas(MZ)=0.1191+-0.0006 (exp), where the uncertainty includes all statistical and systematic experimental uncertainties, but not purely theoretical uncertainties. We study the dependence of the results on the dataset, by providing further determinations based respectively on deep-inelastic data only, and on HERA data only. The deep-inelastic fit gives the consistent result alphas(MZ)=0.1177+-0.0009(exp), but the result of the HERA-only fit is only marginally consistent. We provide evidence that individual data subsets can have runaway directions due to poorly determined PDFs, thus suggesting that a global dataset is necessary for a reliable determination.