Improved Parton Showers at Large Transverse Momenta∗
نویسندگان
چکیده
Several methods to improve the parton-shower description of hard processes by an injection of matrix-element-based information have been presented over the years. In this article we study (re)weighting schemes for the first/hardest emission. One objective is to provide a consistent matching of the POWHEG next-to-leading order generator to the Pythia shower algorithms. Another is to correct the default behaviour of these showers at large transverse momenta, based on a comparison with real-emission matrix elements. ∗Work supported by the Marie Curie Early Stage Training program “HEP-EST” (contract number MEST-CT-2005-019626) and in part by the Marie Curie RTN “MCnet” (contract number MRTN-CT-2006-035606) [email protected] [email protected]
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