PDF dependence of Higgs cross sections at the Tevatron and LHC: response to recent criticism

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Article

Abstract

We respond to some criticism questioning the validity of the current Standard Model Higgs exclusion limits at the Tevatron, due to the significant dependence of the dominant production cross section from gluon-gluon fusion on the choice of parton distribution functions (PDFs) and the strong coupling (αS). We demonstrate the ability of the Tevatron jet data to discriminate between different high-x gluon distributions, performing a detailed quantitative comparison to show that fits not explicitly including these data fail to give a good description. In this context we emphasise the importance of the consistent treatment of luminosity uncertainties. We comment on the values of αS obtained from fitting deep-inelastic scattering data, particularly the fixed-target NMC data, and we show that jet data are needed for stability. We conclude that the Higgs cross-section uncertainties due to PDFs and αS currently used by the Tevatron and LHC experiments are not significantly underestimated, contrary to some recent claims.

Keywords

Higgs Physics Jets Deep Inelastic Scattering Hadronic Colliders 

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© The Author(s) 2011

Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  1. 1.Department of Physics and AstronomyUniversity College LondonLondonU.K.
  2. 2.Theory Group, Physics DepartmentCERNGeneva 23Switzerland

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