We present an NLO simulation of WWbb production with massive b-quarks at the
LHC. Off-shell and non-resonant contributions associated with top-pair and
single-top channels and with leptonic W-boson decays are consistently taken
into account using the complex-mass scheme. Thanks to the finite b-quark mass,
WWbb predictions can be extended to the whole b-quark phase space, thereby
including Wt-channel single-top contributions that originate from collinear
g->bb splittings in the four-flavour scheme. This provides a consistent NLO
description of tt and Wt production and decay, including quantum interference
effects. The simulation is also applicable to exclusive 0- and 1-jet bins,
which is of great importance for Higgs-boson studies in the H->WW channel and
for any other analysis with large top backgrounds and jet vetoes or jet bins.Comment: 8pp. Minor revision, results unchange