The halo light cone catalogues of \Abacus{AbacusSummit}
  We describe a method for generating halo catalogues on the light cone using
the \Abacus{AbacusSummit} suite of $N$-body simulations. The main application
of these catalogues is the construction of realistic mock galaxy catalogues and
weak lensing maps on the sky. Our algorithm associates the haloes from a set of
coarsely-spaced snapshots with their positions at the time of light-cone
crossing by matching halo particles to on-the-fly light cone particles. It then
records the halo and particle information into an easily accessible product,
which we call the \Abacus{AbacusSummit} halo light cone catalogues. Our
recommended use of this product is in the halo mass regime of $M_{\rm halo} >
2.1 \times 10^{11} \ M_\odot/h$ for the \texttt{base} resolution simulations,
i.e. haloes containing at least 100 particles, where the interpolated halo
properties are most reliable. To test the validity of the obtained catalogues,
we perform various visual inspections and consistency checks. In particular, we
construct galaxy mock catalogues of emission-line galaxies (ELGs) at $z \sim 1$
by adopting a modified version of the \Abacus{AbacusHOD} script, which builds
on the standard halo occupation distribution (HOD) method by including various
extensions. We find that the multipoles of the auto-correlation function are
consistent with the predictions from the full-box snapshot, implicitly
validating our algorithm. In addition, we compute and output CMB convergence
maps and find that the auto- and cross-power spectrum agrees with the
theoretical prediction at the subpercent level.
  Halo light cone catalogues for 25 \texttt{base} and 2 \texttt{huge}
simulations at the fiducial cosmology is available at
DOI:\href{https://www.doi.org/10.13139/OLCF/1825069}{10.13139/OLCF/1825069}
