An enquiry on the origins of N-rich stars in the inner Galaxy basedon APOGEE chemical compositions

Abstract

Recent evidence based on APOGEE data for stars within a few kpc of the Galactic centre suggests that dissolved globular clusters (GCs) contribute significantly to the stellar mass budget of the inner halo. In this paper we enquire into the origins of tracers of GC dissolution, N-rich stars, that are located in the inner 4 kpc of the Milky Way. From an analysis of the chemical compositions of these stars we establish that about 30% of the N-rich stars previously identified in the inner Galaxy may have an accreted origin. This result is confirmed by an analysis of the kinematic properties of our sample. The specific frequency of N-rich stars is quite large in the accreted population, exceeding that of its in situ counterparts by near an order of magnitude, in disagreement with predictions from numerical simulations. We hope that our numbers provide a useful test to models of GC formation and destruction.

12 pages including 7 Figures and 1 Appendix. Accepted for publication by MNRAS

References in corpus (37)

• The Gaia mission
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• galpy: A Python Library for Galactic Dynamics
• The mass distribution and gravitational potential of the Milky Way
• Evidence for Two Early Accretion Events That Built the Milky Way Stellar Halo
• APOGEE Data and Spectral Analysis from SDSS Data Release 16: Seven Years of Observations Including First Results from APOGEE-South
• Streams, substructures and the early history of the Milky Way
• The ACS Nearby Galaxy Survey Treasury IX. Constraining asymptotic giant branch evolution with old metal-poor galaxies
• The Apache Point Observatory Galactic Evolution Experiment (APOGEE) Spectrographs
• Target Selection for the SDSS-IV APOGEE-2 Survey
• Kraken reveals itself -- the merger history of the Milky Way reconstructed with the E-MOSAICS simulations
• Evidence from APOGEE for the presence of a major building block of the halo buried in the inner Galaxy
• The age-metallicity structure of the Milky Way disk
• Constraining the thick disc formation scenario of the Milky Way
• Exploring Anticorrelations and Light Element Variations in Northern Globular Clusters Observed by the APOGEE Survey
• Disentangling the Galactic Halo with APOGEE: I. Chemical and Kinematical Investigation of Distinct Metal-Poor Populations
• New H-band Stellar Spectral Libraries for the SDSS-III/APOGEE survey
• The Chemical Compositions of Accreted and {\it in situ} Galactic Globular Clusters According to SDSS/APOGEE
• A homogeneous analysis of globular clusters from the APOGEE survey with the BACCHUS code. I. The Northern clusters
• Touching The Void: A Striking Drop in Stellar Halo Density Beyond 50 kpc
• The Gaia-ESO Survey: A globular cluster escapee in the Galactic halo
• The Relationship Between Globular Cluster Mass, Metallicity, and Light Element Abundance Variations
• Chemodynamics of newly identified giants with globular cluster like abundance patterns in the bulge, disk, and halo of the Milky Way
• The contribution of N-rich stars to the Galactic stellar halo using APOGEE red giants
• Exploring the stellar age distribution of the Milky Way Bulge using APOGEE
• The Populations of Carina. II. Chemical Enrichment
• Purveyors of fine halos: Re-assessing globular cluster contributions to the Milky Way halo build-up with SDSS-IV
• Phosphorus-rich stars with unusual abundances are challenging theoretical predictions
• Predicting accreted satellite galaxy masses and accretion redshifts based on globular cluster orbits in the E-MOSAICS simulations
• The [α/Fe]-[Fe/H] relation in the E-MOSAICS simulations: its connection to the birth place of globular clusters and the fraction of globular cluster field stars in the bulge
• Purveyors of fine halos. II. Chemodynamical association of halo stars with Milky Way globular clusters
• The mass fraction of halo stars contributed by the disruption of globular clusters in the E-MOSAICS simulations
• Formation of N-rich field stars in the high-density building blocks of the Galactic bulge
• On the Chemical and Kinematic Consistency Between N-rich Metal-poor Field Stars and Enriched Populations in Globular Clusters
• Gaia DR2 orbital properties for field stars with globular cluster-like CN band strengths
• Heavy element abundances in P-rich stars: A new site for the s-process?
• The building blocks of the Milky Way halo using APOGEE and Gaia -- or -- Is the Galaxy a typical galaxy?

Cited by in corpus (11)

• Nitrogen enrichment and clustered star formation at the dawn of the Galaxy
• The evolution of CNO elements in galaxies
• Galactic ArchaeoLogIcaL ExcavatiOns (GALILEO) I. An updated census of APOGEE N-rich giants across the Milky Way
• The observable properties of galaxy accretion events in Milky Way-like galaxies in the FIRE-2 cosmological simulations
• Hidden in the Haystack: Low-luminosity globular clusters towards the Milky Way bulge
• Nitrogen evolution in the halo, thick disc, thin disc and bulge of the Galaxy
• APOGEE Detection of N-rich stars in the tidal tails of Palomar 5
• Chemical tagging with APOGEE, MUSE, and HST: constraints on the formation of $\omega$ Centauri
• The dawn is quiet here: Rise in [$\alpha$/Fe] is a signature of massive gas accretion that fueled proto-Milky Way
• Unravelling the role of merger histories in the population of In situ stars: linking IllustrisTNG cosmological simulation to H3 survey
• Blanco DECam Bulge Survey (BDBS) IV: Metallicity Distributions and Bulge Structure from 2.6 Million Red Clump Stars