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arXiv · 1204.4424

The Matrix Element Method at Next-to-Leading Order

John M. Campbell·Walter T. Giele·Ciaran Williams
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Abstract

This paper presents an extension of the matrix element method to next-to-leading order in perturbation theory. 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.

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John M. Campbell, Walter T. Giele, Ciaran Williams. 2012-04-19. The Matrix Element Method at Next-to-Leading Order. https://doi.org/10.1007/jhep11(2012)043

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