All quiet in the outer halo: chemical abundances in the globular cluster
  Pal 3
  Context: Globular clusters (GCs) in the outer halo are important probes of
the composition and origin of the Galactic stellar halo.
  Aims: We derive chemical element abundance ratios in red giants belonging to
the remote (R~90 kpc) GC Pal 3 and compare our measurements to those for red
giant stars in both inner and outer halo GCs.
  Methods: From high-resolution spectroscopy of four red giants, obtained with
the Magellan/MIKE spectrograph at moderately high S/N, we derive chemical
abundances for 25 alpha-, iron peak-, and neutron-capture elements. These
abundance ratios are confirmed by co-adding low S/N HIRES spectra of 19 stars
along the red giant branch.
  Results: Pal 3 shows alpha-enhanced abundance patterns, and also its Fe-peak
and neutron-capture element ratios, are fully compatible with those found in
halo field stars and representative inner halo GCs of the same metallicity
(such as M 13). The heavy elements in Pal 3 appear to be governed by r-process
nucleosyn-thesis. Our limited sample does not show any significant star-to-star
abundance variations in this cluster, although a weak Na-O anti-correlation
cannot be ruled out by the present data.
  Conclusions: Pal 3 thus appears as an archetypical GC with abundance ratios
dissimilar to dwarf spheroidal stars, ruling out a direct connection to such
external systems. This conclusion is underscored by the lack of significant
abundance spreads in this GC, in contrast to the broad abundance distributions
seen in the dwarf galaxies. Pal 3 appears to have evolved chemically coeval
with the majority of GCs belonging to Galactic inner and outer halo,
experiencing a similar enrichment history.
