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Journal of High Energy Physics

, 2012:43 | Cite as

The matrix element method at next-to-leading order

  • John M. Campbell
  • Walter T. Giele
  • Ciaran Williams
Open Access
Article

Abstract

This paper presents an extension of the matrix element method to next-to-leading order in perturbation theory, for electro-weak final states. To accomplish this we have developed a method to calculate next-to-leading order weights on an event-by-event basis. This allows for the definition of next-to-leading order likelihoods in exactly the same fashion as at leading order, thus extending the matrix element method to next-to-leading order. A welcome by-product of the method is the straightforward and efficient generation of unweighted next-to-leading order events. As examples of the application of our next-to-leading order matrix element method we consider the measurement of the mass of the Z boson and also the search for the Higgs boson in the four lepton channel.

Keywords

NLO Computations Hadronic Colliders 

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Copyright information

© SISSA 2012

Authors and Affiliations

  • John M. Campbell
    • 1
  • Walter T. Giele
    • 1
  • Ciaran Williams
    • 1
  1. 1.FermilabBataviaU.S.A.

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