\midheading{$ZH$ production, processes 101--110}
\label{subsec:zh}

These processes represent the production of a $Z$ boson (or virtual photon)
in association with a Standard Model Higgs boson that
decays into a bottom quark pair ({\tt nproc=101-103}),
or decays into a pair of photons ({\tt nproc=104-105})
or a pair of $W$ bosons ({\tt nproc=106-108}),
or a pair of $Z$ bosons ({\tt nproc=109}),
or a pair of $\tau$'s ({\tt nproc=110}).

The $Z$ subsequently decays into
either an $e^+ e^-$ pair ({\tt nproc=101, 106, 109}), neutrinos ({\tt nproc=102, 107})
or a bottom quark pair ({\tt nproc=103, 108}).
The calculation may be performed at NLO, although radiation from the
bottom quarks in the decay of the Higgs (or the $Z$, for processes
{\tt 103, 108}) is not included.
Radiation from the bottom quarks in the decay of the Higgs is included in ({\tt nproc=1010}).

When {\tt removebr} is true in processes {\tt 101, 106, 109}, neither the $Z$ boson
nor the Higgs decays.

For more information on this
process see refs.~\cite{Campbell:2016jau,Boughezal:2016wmq,Campbell:2022gdq}.
NLO calculations can be performed by subtraction, zero-jettiness
slicing and $q_T$-slicing.  NNLO calculations can be performed by
zero-jettiness slicing and $q_T$-slicing.