The Near-Infrared Spectrum of the Nuclear Star Cluster: Looking Below
  the Tip of the Iceberg and Comparisons with Extragalactic Nuclei
  Long-slit near-infrared (NIR) spectra of the Galactic nuclear star cluster
(NSC) are discussed. The spectra sample the major axis of the NSC out to its
half light radius. The equivalent widths of NaI2.21um and CaI2.26um outside of
the center of the NSC, where light from nuclear bulge stars contributes a large
fraction to the total flux, are consistent with solar chemical mixtures. In
contrast, the equivalent widths of NaI2.21um and CaI2.26um near the center of
the NSC are larger than expected from models with solar chemical mixtures, even
after light from the brightest evolved stars is removed. That NaI2.21um and
CaI2.26um are deeper than predicted for solar chemical mixtures over a range of
evolutionary states is consistent with previous studies that find that the
majority of stars near the center of the NSC formed from material that had
non-solar chemical mixtures. A spectrum of nebular emission and the youngest
stars near the GC is also extracted. The equivalent widths of emission features
in the extracted NIR spectrum are similar to those in the nuclear spectrum of
NGC 253, and it is argued that this agreement is best achieved if the current
episode of star formation near the center of the NSC has been in progress for
at least a few Myr.
