Metal-poor stars towards the Galactic bulge - a population potpourri
  We present a comprehensive chemical abundance analysis of five red giants and
two horizontal branch (HB) stars towards the southern Galactic bulge, at
(l,b)$\sim$(0$^{\rm o}$,-11$^{\rm o}$). Based on high-resolution spectroscopy
obtained with the Magellan/MIKE spectrograph, we derived up to 23 chemical
element abundances and identify a mixed bag of stars, representing various
populations in the central regions of the Galaxy. Although cosmological
simulations predict that the inner Galaxy was host to the first stars in the
Universe, we see no chemical evidence of the ensuing massive supernova
explosions: all of our targets exhibit halo-like, solar [Sc/Fe] ratios, which
is in contrast to the low values predicted from Population III nucleosynthesis.
One of the targets is a CEMP-s star at [Fe/H]=-2.52 dex, and another one is a
moderately metal-poor ([Fe/H]=-1.53 dex) CH star with strong enrichment in
s-process elements (e.g., [Ba/Fe]=1.35). These individuals provide the first
contenders of these classes of stars towards the bulge. Four of the
carbon-normal stars exhibit abundance patterns reminiscent of halo star across
a metallicity range spanning -2.0 to -2.6 dex, i.e., enhanced $\alpha$-elements
and solar Fe-peak and n-capture elements, and the remaining one is a regular
metal-rich bulge giant. The position, distance, and radial velocity of one of
the metal-poor HB stars coincides with the old trailing arm of the disrupted
Sagittarius dwarf galaxy. While their uncertain proper motions prohibit a clear
kinematic separation, the stars' abundances and distances suggest that these
metal-poor candidates, albeit located towards the bulge, are not of the bulge,
but rather inner halo stars on orbits that make them pass through the central
regions. Thus, we caution similar claims of detections of metal-poor stars as
true habitants of the bulge. (Abridged)
