Fornax 3D project: automated detection of planetary nebulae in the
  centres of early-type galaxies and first results
  Extragalactic planetary nebulae (PNe) are detectable through relatively
strong nebulous [OIII] emission and act as direct probes into the local stellar
population. Because they have an apparently universal invariant magnitude
cut-off, PNe are also considered to be a remarkable standard candle for
distance estimation. Through detecting PNe within the galaxies, we aim to
connect the relative abundances of PNe to the properties of their host galaxy
stellar population. By removing the stellar background components from FCC 167
and FCC 219, we aim to produce PN luminosity functions (PNLF) of these
galaxies, and thereby also estimate the distance modulus to these two systems.
Finally, we test the reliability and robustness of our novel detection and
analysis method. It detects unresolved point sources by their [OIII] 5007{\AA}
emission within regions that have previously been unexplored. We model the
[OIII] emissions in the spatial and spectral dimensions together, as afforded
to us by the Multi Unit Spectroscopic Explorer (MUSE), and we draw on data
gathered as part of the Fornax3D survey. For each source, we inspect the
properties of the nebular emission lines to remove other sources that might
hinder the safe construction of the PNLF, such as supernova remnants and HII
regions. As a further step, we characterise any potential limitations and draw
conclusions about the reliability of our modelling approach through a set of
simulations. By applying this novel detection and modelling approach to
integral field unit observations, we report for the distance estimates and
luminosity-specific PNe frequency values for the two galaxies. Furthermore, we
include an overview of source contamination, galaxy differences, and possible
effects on the PNe populations in the dense stellar environments.
