Chemodynamics of newly identified giants with globular cluster like abundance patterns in the bulge, disk, and halo of the Milky Way
2019
The latest edition of the APOGEE-2/DR14 survey catalogue and the first \texttt{Payne} data release of APOGEE abundance determinations by Ting et al. are examined. We identify 31 previously unremarked metal-poor
giant starswith anomalously high levels of nitrogen in the
chemical spacedefined by [Fe/H] and [N/Fe]. The APOGEE chemical abundance patterns of such objects revealed that these are chemically distinct from the
Milky Way(MW) in most
chemical elements. We have found all these objects have a [N/Fe]$>+0.5$, and are thus identified here as nitrogen-rich stars. An orbital analysis of these objects revealed that a handful of them shares the orbital properties of the bar/bulge, and possibly linked to tidal debris of surviving
globular clusterstrapped into the bar component. 3 of the 31 stars are actually halo interlopers into the bulge area, which suggests that halo contamination is not insignificant when studying N-rich stars found in the inner Galaxy, whereas the rest of the N-rich stars share orbital properties with the halo population. Most of the newly identified population exhibit chemistry similar to the so-called \textit{second-generation}
globular clusterstars (enriched in aluminum, [Al/Fe]$>+0.5$), whereas a handful of them exhibit lower abundances of aluminum, [Al/Fe]$<+0.5$, which are thought to be chemically associated with the \textit{first-generation} of stars, as seen in
globular clusters, or compatible with origin from a tidally disrupted
dwarf galaxy.
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