Line list from Pal 13 sample stars

We find a metal-poor mean metallicity of -1.91+/-0.05 (statistical) +/-0.22 (systematic), confirming that Pal 13 is a typical metal-poor representative of the outer halo. While there are some differences between individual {alpha}-elements, such as halo-like Mg and Si versus the mildly lower Ca and Ti abundances, the mean [{alpha}/Fe] of 0.34+/-0.06 is consistent with the marginally lower {alpha} component of the halo field and GC stars at similar metallicity.

We discuss our results in the context of other objects in the outer halo and consider which of these objects were likely accreted. We also discuss the properties of their progenitors. While chemically, Pal 13 is similar to Gaia-Enceladus and some of its GCs, this is not supported by its kinematic properties within the Milky Way system.

Moreover, its chemodynamical similarity with NGC 5466, a purported progeny of the Sequoia accretion event, might indicate a common origin in this progenitor. However, the ambiguities in the full abundance space of this comparison emphasize the difficulties in unequivocally labeling a single GC as an accreted object, let alone assigning it to a single progenitor.