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Unitarising matrix element + parton shower merging. (English) Zbl 1342.81693

Summary: We revisit the CKKW-L method for merging tree-level matrix elements with parton showers, and amend it with an add/subtract scheme to minimise dependencies on the merging scale. The scheme is constructed to, as far as possible, recover the unitary nature of the underlying parton shower, so that the inclusive cross section is retained for each jet multiplicity separately.

MSC:

81V05 Strong interaction, including quantum chromodynamics
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