An analysis of the composite stellar population in M32
  We obtained long-slit spectra of high signal-to-noise ratio of the galaxy M32
with the GMOS spectrograph at the GEMINI North telescope. We analysed the
integrated spectra by means of full spectral fitting in order to extract the
mixture of stellar populations that best represents its composite nature. Three
different galactic radii were analysed, from the nuclear region out to 2 arcmin
from the centre. This allows us to compare, for the first time, the results of
integrated light spectroscopy with those of resolved colour-magnitude diagrams
from the literature. As our main result, we propose that an ancient and an
intermediate-age population coexist in M32, and that the balance between these
two populations change between the nucleus and outside 1 effective radius in
the sense that the contribution from the intermediate population is larger at
the nuclear region. We retrieve a smaller signal of a young population at all
radii whose origin is unclear and may be a contamination from horizontal-branch
stars, such as the ones identified by Brown et al. in the nuclear region. We
compare our metallicity distribution function for a region 1 to 2 arcmin from
the centre to the one obtained with photometric data by Grillmair et al. Both
distributions are broad, but our spectroscopically derived distribution has a
significant component with $[Z/Z_{\sun}] \leq -1$, which is not found by
Grillmair et al.
