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arXiv · 2112.02117

APOGEE Detection of N-rich stars in the tidal tails of Palomar 5

Sian G. Phillips·Ricardo P. Schiavon·J. Ted Mackereth·Carlos Allende Prieto·Borja Anguiano·Rachael L. Beaton·Roger E. Cohen·D. A. Garcia-Hernandez·Douglas Geisler·Danny Horta·Henrik Jonsson·Shobhit Kisku·Richard R. Lane·Steven R. Majewski·Andrew Mason·Dante Minniti·Mathias Schultheis·Dominic Taylor
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Abstract

Recent results from chemical tagging studies using APOGEE data suggest a strong link between the chemical abundance patterns of stars found within globular clusters, and chemically peculiar populations in the Galactic halo field. In this paper we analyse the chemical compositions of stars within the cluster body and tidal streams of Palomar 5, a globular cluster that is being tidally disrupted by interaction with the Galactic gravitational potential. We report the identification of nitrogen-rich (N-rich) stars both within and beyond the tidal radius of Palomar 5, with the latter being clearly aligned with the cluster tidal streams; this acts as confirmation that N-rich stars are lost to the Galactic halo from globular clusters, and provides support to the hypothesis that field N-rich stars identified by various groups have a globular cluster origin.

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Sian G. Phillips, Ricardo P. Schiavon, J. Ted Mackereth, Carlos Allende Prieto, Borja Anguiano, Rachael L. Beaton, Roger E. Cohen, D. A. Garcia-Hernandez, Douglas Geisler, Danny Horta, Henrik Jonsson, Shobhit Kisku, Richard R. Lane, Steven R. Majewski, Andrew Mason, Dante Minniti, Mathias Schultheis, Dominic Taylor. 2021-12-03. APOGEE Detection of N-rich stars in the tidal tails of Palomar 5. https://doi.org/10.1093/mnras%2Fstab3532

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