\midheading{$WH$ production, process 609}
This process represents the production of $W$ and $H$ bosons in
association with a jet, with the subsequent decay $H \to \tau^+ \tau^-$.
Both charges of the $W$ boson are summed over and, as a result, the
decay products of the $W$ boson, particles 3 and 4,
represent lepton and antilepton respectively (i.e. they do not correspond
to a neutrino and charged lepton).
It is primarily of interest as a component
part of the NNLO contributions to $WH$ production.
For further information see ref.~\cite{Campbell:2016jau}.
This process is calculable at leading LO and next-to-leading order NLO.