Galactic ArchaeoLogIcaL ExcavatiOns (GALILEO) I. An updated census of APOGEE N-rich giants across the Milky Way

Abstract

(ABRIDGED) We use the 17th data release of the second phase of the Apache Point Observatory Galactic Evolution Experiment (APOGEE-2) to provide a homogenous census of N-rich red giant stars across the Milky Way (MW). We report a total of 149 newly identified N-rich field giants toward the bulge, metal-poor disk, and halo of our Galaxy. They exhibit significant enrichment in their nitrogen abundance ratios ([N/Fe] $\gtrsim +0.5$), along with simultaneous depletions in their [C/Fe] abundance ratios ([C/Fe] $<+0.15$), and they cover a wide range of metallicities ($-1.8<$ [Fe/H] $<-0.7$). The final sample of candidate N-rich red giant stars with globular-cluster-like (GC-like) abundance patterns from the APOGEE survey includes a grand total of $\sim$ 412 unique objects. These strongly N-enhanced stars are speculated to have been stripped from GCs based on their chemical similarities with these systems. Even though we have not found any strong evidence for binary companions or signatures of pulsating variability yet, we cannot rule out the possibility that some of these objects were members of binary systems in the past and/or are currently part of a variable system. In particular, the fact that we identify such stars among the field stars in our Galaxy provides strong evidence that the nucleosynthetic process(es) producing the anomalous [N/Fe] abundance ratios occurs over a wide range of metallicities. This may provide evidence either for or against the uniqueness of the progenitor stars to GCs and/or the existence of chemical anomalies associated with likely tidally shredded clusters in massive dwarf galaxies such as "Kraken/Koala," \textit{Gaia}-Enceladus-Sausage, among others, before or during their accretion by the MW. A dynamical analysis reveals that the newly identified N-rich stars exhibit a wide range of dynamical characteristics throughout the MW, ...

arXiv commentAccepted to Astronomy & Astrophysics. 12 pages, 5 figures, and 3 tables

References in corpus (111)

• The 2.5 m Telescope of the Sloan Digital Sky Survey
• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
• The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
• Co-formation of the Galactic disc and the stellar halo
• ASPCAP: The Apogee Stellar Parameter and Chemical Abundances Pipeline
• Kinematics of Metal-Poor Stars in the Galaxy. III. Formation of the Stellar Halo and Thick Disk as Revealed from a Large Sample of Non-Kinematically Selected Stars
• Gaia Data Release 2: Kinematics of globular clusters and dwarf galaxies around the Milky Way
• Debris streams in the solar neighbourhood as relicts from the formation of the Milky Way
• Determining stellar atmospheric parameters and chemical abundances of FGK stars with iSpec
• Evidence for Two Early Accretion Events That Built the Milky Way Stellar Halo
• Gaia EDR3 view on Galactic globular clusters
• The Data Reduction Pipeline for the Apache Point Observatory Galactic Evolution Experiment
• Abundances, Stellar Parameters, and Spectra From the SDSS-III/APOGEE Survey
• Target Selection for the Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• Streams, substructures and the early history of the Milky Way
• Accurate distances to Galactic globular clusters through a combination of Gaia EDR3, HST and literature data
• Rapid Reionization by the Oligarchs: The Case for Massive, UV-Bright, Star-Forming Galaxies with High Escape Fractions
• Target Selection for the SDSS-IV APOGEE-2 Survey
• APOGEE Data Releases 13 and 14: Data and Analysis
• Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18
• Kraken reveals itself -- the merger history of the Milky Way reconstructed with the E-MOSAICS simulations
• Multiple retrograde substructures in the Galactic halo: A shattered view of Galactic history
• Rings and Radial Waves in the Disk of the Milky Way
• StarHorse: A Bayesian tool for determining stellar masses, ages, distances, and extinctions for field stars
• Evidence from APOGEE for the presence of a major building block of the halo buried in the inner Galaxy
• Gaia Early Data Release 3: Summary of the contents and survey properties
• Life in the fast lane: a direct view of the dynamics, formation, and evolution of the Milky Way's bar
• Chemodynamical history of the Galactic Bulge
• Chemical tagging with APOGEE: Discovery of a large population of N-rich stars in the inner Galaxy
• From the bulge to the outer disc: StarHorse stellar parameters, distances, and extinctions for stars in APOGEE DR16 and other spectroscopic surveys
• The SDSS-III APOGEE Spectral Line List for H-band Spectroscopy
• Charting the Galactic acceleration field I. A search for stellar streams with Gaia DR2 and EDR3 with follow-up from ESPaDOnS and UVES
• The Global Dynamical Atlas of the Milky Way mergers: Constraints from Gaia EDR3 based orbits of globular clusters, stellar streams and satellite galaxies
• Reverse engineering the Milky Way
• Homogeneous Analysis of Globular Clusters from the APOGEE Survey with the BACCHUS Code. II. The Southern Clusters and Overview
• APOGEE Data Releases 13 and 14: Stellar Parameter and Abundance Comparisons With Independent Analyses
• The APOGEE Data Release 16 Spectral Line List
• The pattern speed of the Milky Way bar from transverse velocities
• Ages and kinematics of chemically selected, accreted Milky Way halo stars
• New H-band Stellar Spectral Libraries for the SDSS-III/APOGEE survey
• The Milky Way bar and bulge revealed by APOGEE DR16 and Gaia EDR3
• The $R$-Process Alliance: Fourth Data Release from the Search for $r$-Process-Enhanced Stars in the Galactic Halo
• Final Targeting Strategy for the SDSS-IV APOGEE-2S Survey
• Final Targeting Strategy for the SDSS-IV APOGEE-2N Survey
• A Sequoia in the Garden: FSR 1758 - Dwarf Galaxy or Giant Globular Cluster?
• A Search for Nitrogen-Enhanced Metal-Poor Stars
• A homogeneous analysis of globular clusters from the APOGEE survey with the BACCHUS code. I. The Northern clusters
• APOGEE Chemical Abundances of the Sagittarius Dwarf Galaxy
• Dissecting stellar chemical abundance space with t-SNE
• Chemical tagging in the SDSS-III/APOGEE survey: new identifications of halo stars with globular cluster origins
• The metallicity spread and the age-metallicity relation of Omega Centauri
• Atypical Mg-poor Milky Way field stars with globular cluster second-generation like chemical patterns
• Exploring Halo Substructure with Giant Stars: Substructure in the Local Halo as Seen in the Grid Giant Star Survey Including Extended Tidal Debris from Omega Centauri
• The ASAS-SN Catalog of Variable Stars IX: The Spectroscopic Properties of Galactic Variable Stars
• The eye of Gaia on globular clusters structure: tidal tails
• Discovery of a Metal-Poor Field Giant with a Globular Cluster Second-Generation Abundance Pattern
• A stellar stream remnant of a globular cluster below the metallicity floor
• The tidal remnant of an unusually metal-poor globular cluster
• The R-Process Alliance: Chemo-Dynamically Tagged Groups of Halo $r$-Process-Enhanced Stars Reveal a Shared Chemical-Evolution History
• Characterizing the High-Velocity Stars of RAVE: The Discovery of a Metal-Rich Halo Star Born in the Galactic Disk
• The Gaia-ESO Survey: A globular cluster escapee in the Galactic halo
• The Sun was not born in M 67
• Chemodynamics of newly identified giants with globular cluster like abundance patterns in the bulge, disk, and halo of the Milky Way
• Spectroscopic Signatures of Extra-Tidal Stars Around the Globular Clusters NGC 6656 (M22), NGC 3201 and NGC 1851 from RAVE
• Phosphorus-rich stars with unusual abundances are challenging theoretical predictions
• Aluminum Enhanced Metal-Poor Stars buried in the Inner Galaxy
• Identifying Sagittarius Stream Stars By Their APOGEE Chemical Abundance Signatures
• The Gaia-ESO Survey: low-alpha element stars in the Galactic Bulge
• Dynamically Tagged Groups of Metal-Poor Stars from the Best \& Brightest Survey
• CAPOS: The bulge Cluster APOgee Survey I. Overview and initial ASPCAP results
• Discovery of a new stellar sub-population residing in the (inner) stellar halo of the Milky Way
• Homogeneous Analysis of Globular Clusters from the APOGEE Survey with the BACCHUS Code $-$ III. $\omega$ Cen
• H-band discovery of additional Second-Generation stars in the Galactic Bulge Globular Cluster NGC 6522 as observed by APOGEE and Gaia
• Search for Extra-Tidal RR Lyrae Stars in Milky Way Globular Clusters From Gaia DR2
• Purveyors of fine halos. II. Chemodynamical association of halo stars with Milky Way globular clusters
• Dynamical Orbital classification of selected N-rich stars with \textit{Gaia} DR2 astrometry
• A Spectroscopic Survey for Omega Centauri Members at and beyond the Cluster Tidal Radius
• VVV CL001: Likely the Most Metal-Poor Surviving Globular Cluster in the Inner Galaxy
• Chemical analysis of CH stars - II: atmospheric parameters and elemental abundances
• The enigmatic globular cluster UKS~1 obscured by the bulge: \textit{H}-band discovery of nitrogen-enhanced stars
• Searching for tidal tails around $\omega$ Centauri using RR Lyrae Stars
• CN Anomalies in the Halo System and the Origin of Globular Clusters in the Milky Way
• Chemical and kinematic analysis of CN-strong Metal-poor Field Stars in LAMOST DR3
• APOGEE discovery of a chemically atypical star disrupted from NGC 6723 and captured by the Milky Way bulge
• Discovery of a nitrogen-enhanced mildly metal-poor binary system: Possible evidence for pollution from an extinct AGB Star
• APOGEE spectroscopic evidence for chemical anomalies in dwarf galaxies: The case of M~54 and Sagittarius
• Jurassic: A Chemically Anomalous Structure in the Galactic Halo
• Discovery of a large population of Nitrogen-Enhanced stars in the Magellanic Clouds
• RAVE stars tidally stripped/ejected from $\omega$ Centauri globular cluster
• CAPOS: the bulge Cluster APOgee Survey II. The Intriguing "Sequoia" Globular Cluster FSR 1758
• Formation of N-rich field stars in the high-density building blocks of the Galactic bulge
• Discovery of Tidal RR LYRAE stars in the Bulge Globular Cluster M 62
• On the Chemical and Kinematic Consistency Between N-rich Metal-poor Field Stars and Enriched Populations in Globular Clusters
• The Tale of the Milky Way Globular Cluster NGC 6362 -- I. The Orbit and its possible extended star debris features as revealed by Gaia DR2
• CAPOS: The bulge Cluster APOgee Survey III. Spectroscopic Tomography of Tonantzintla 2
• STREGA: STRucture and Evolution of the GAlaxy. I. Survey Overview and First Results
• APOGEE-2S Discovery of Light- and Heavy-Element Abundance Correlations in the Bulge Globular Cluster NGC 6380
• An enquiry on the origins of N-rich stars in the inner Galaxy basedon APOGEE chemical compositions
• APOGEE-2S view of the globular cluster Patchick 125 (Gran 3). New metallicity and elemental abundances from high-resolution spectroscopy
• Heavy element abundances in P-rich stars: A new site for the s-process?
• The search for extratidal star candidates around Galactic globular clusters NGC 2808, NGC 6266, and NGC 6397 with {\textit{Gaia}} DR2 astrometry
• A Nitrogen-Enhanced Metal-Poor star discovered in the globular cluster ESO280-SC06
• Close encounters involving RAVE stars beyond the 47 Tucanae tidal radius
• APOGEE-2 Discovery of a Large Population of Relatively High-Metallicity Globular Cluster Debris
• APOGEE Detection of N-rich stars in the tidal tails of Palomar 5
• On the discovery of K-enhanced and possibly Mg-depleted stars throughout the Milky Way
• The s-process enriched star HD 55496: origin from a globular cluster or from the tidal disruption of a dwarf galaxy?
• Chemical Tagging N-rich Field Stars with High-resolution Spectroscopy
• Determination of Sodium Abundance Ratio from Low-Resolution Stellar Spectra and Its Applications

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• StarHorse results for spectroscopic surveys + Gaia DR3: Chrono-chemical populations in the solar vicinity, the genuine thick disk, and young-alpha rich stars
• Nitrogen enrichment and clustered star formation at the dawn of the Galaxy
• Nature vs. Nurture: Distinguishing Effects from Stellar Processing and Chemical Evolution on Carbon and Nitrogen in Red Giant Stars
• Abundance analysis of APOGEE spectra for 58 metal-poor stars from the bulge spheroid
• Multiple stellar population mass loss in massive Galactic globular clusters
• Galactic ArchaeoLogIcaL ExcavatiOns (GALILEO) II. t-SNE Portrait of Local Fossil Relics and Structures
• Chrono-chemodynamical analysis of the globular cluster NGC 6355: Looking for the fundamental bricks of the Bulge
• High-resolution near-infrared spectroscopy of globular cluster and field stars toward the Galactic bulge
• Near-infrared chemical abundances of stars in the Sculptor dwarf galaxy
• Chronology of our Galaxy from Gaia colour-magnitude diagram fitting (ChronoGal) II. Unveiling the formation and evolution of the kinematically selected Thick and Thin Discs
• CAPOS: The bulge Cluster APOgee Survey V. Elemental abundances of the bulge globular cluster HP 1
• Detailed analysis of a sample of field metal-poor N-rich dwarfs
• Exploring the ex-situ components within Gaia DR3
• Not all nitrogen-rich field stars originate from globular clusters
• APOGEE chemical abundances of stars in the MW satellites Fornax, Sextans, Draco and Carina