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arXiv · hep-ph/0109231

QCD Matrix Elements + Parton Showers

S. Catani·F. Krauss·R. Kuhn·B. R. Webber
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Abstract

We propose a method for combining QCD matrix elements and parton showers in Monte Carlo simulations of hadronic final states in $e^+e^-$ annihilation. The matrix element and parton shower domains are separated at some value $y_{ini}$ of the jet resolution, defined according to the $k_T$-clustering algorithm. The matrix elements are modified by Sudakov form factors and the parton showers are subjected to a veto procedure to cancel dependence on $y_{ini}$ to next-to-leading logarithmic accuracy. The method provides a leading-order description of hard multi-jet configurations together with jet fragmentation, while avoiding the most serious problems of double counting. We present first results of an approximate implementation using the event generator APACIC++.

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S. Catani, F. Krauss, R. Kuhn, B. R. Webber. 2001-09-25. QCD Matrix Elements + Parton Showers. https://doi.org/10.1088/1126-6708%2F2001%2F11%2F063

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