Iron and neutron-capture element abundance variations in the globular cluster M2 (NGC 7089)

Abstract

We present CN and CH indices and CaII triplet metallicities for 34 giant stars and chemical abundances for 33 elements in 14 giants in the globular cluster M2. Assuming the program stars are cluster members, our analysis reveals (i) an extreme variation in CN and CH line strengths, (ii) a metallicity dispersion with a dominant peak at [Fe/H] = -1.7 and smaller peaks at -1.5 and -1.0, (iii) star-to-star abundance variations and correlations for the light elements O, Na, Al and Si and (iv) a large (and possibly bimodal) distribution in the abundances of all elements produced mainly via the s-process in solar system material. Following Roederer et al. (2011), we define two groups of stars, "r+s" and "r-only", and subtract the average abundances of the latter from the former group to obtain a "s-process residual". This s-process residual is remarkably similar to that found in M22 and in M4 despite the range in metallicity covered by these three systems. With recent studies identifying a double subgiant branch in M2 and a dispersion in Sr and Ba abundances, our spectroscopic analysis confirms that this globular cluster has experienced a complex formation history with similarities to M22, NGC 1851 and omega Centauri.

arXiv commentAccepted for publication in MNRAS

References in corpus (82)

• The chemical composition of the Sun
• The Dartmouth Stellar Evolution Database
• Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
• Fast rotating massive stars and the origin of the abundance patterns in galactic globular clusters
• Intrinsic iron spread and a new metallicity scale for Globular Clusters
• Formation and Dynamical Evolution of Multiple Stellar Generations in Globular Clusters
• Star counts in the Galaxy. Simulating from very deep to very shallow photometric surveys with the TRILEGAL code
• The effective temperature scale of FGK stars. II. Teff : color : [Fe/H] calibrations
• Omega Centauri: The Population Puzzle Goes Deeper
• Abundances and Kinematics of Field Halo and Disk Stars I: Observational Data and Abundance Analysis
• Evolution, nucleosynthesis and yields of low mass AGB stars
• Nucleosynthesis and mixing on the Asymptotic Giant Branch. III. Predicted and observed s-process abundances
• Massive binaries as the source of abundance anomalies in globular clusters
• Evolution, nucleosynthesis and yields of low mass AGB stars at different metallicities (II): the FRUITY database
• The Galactic Thick Disk Stellar Abundances
• Formation of omega Centauri from an ancient nucleated dwarf galaxy in the young Galactic disc
• Chemical Abundances for 855 Giants in the Globular Cluster Omega Centauri (NGC 5139)
• Abundances for metal-poor stars with accurate parallaxes I. Basic data
• The Chemical Composition and Age of the Metal-Poor Halo Star BD +17^\circ 3248
• S4N: A Spectroscopic Survey of Stars in the Solar Neighborhood
• The Abundances of Neutron Capture Species in the Very Metal-Poor Globular Cluster M15: An Uniform Analysis of RGB and RHB Stars
• The ACS Survey of Galactic Globular Clusters. III. The Double Subgiant Branch of NGC 1851
• Star-to-Star Abundance Variations among Bright Giants in the Mildly Metal-Poor Globular Cluster M4
• DAOSPEC: an automatic code for measuring equivalent widths in high-resolution stellar spectra
• The s-Process in Low Metallicity Stars. II. Interpretation of High-Resolution Spectroscopic Observations with AGB models
• Near-UV Observations of HD221170: New Insights into the Nature of r-Process-Rich Stars
• Detailed abundances of a large sample of giant stars in M 54 and in the Sagittarius nucleus
• Hot Horizontal-Branch Stars: The Ubiquitous Nature of the "Jump" in Stromgren u, Low Gravities, and the Role of Radiative Levitation of Metals
• Abundances in Stars from the Red Giant Branch Tip to Near the Main Sequence Turn Off in M71: III. Abundance Ratios
• New Rare Earth Element Abundance Distributions for the Sun and Five r-Process-Rich Very Metal-Poor Stars
• The two metallicity groups of the globular cluster M22: a chemical perspective
• New Analyses of Star-to-Star Abundance Variations Among Bright Giants in the Mildly Metal-Poor Globular Cluster M5
• The Ubiquity of the Rapid Neutron-Capture Process
• Multiple stellar populations in the globular cluster NGC 1851
• An abundance analysis of bright giants in the globular cluster NGC 1851
• Detection of Elements at All Three r-process Peaks in the Metal-Poor Star HD 160617
• On the Formation of Multiple Stellar Populations in Globular Clusters
• A double stellar generation in the Globular Cluster NGC6656 (M 22). Two stellar groups with different iron and s-process element abundance
• Abundances in giant stars of the globular cluster NGC 6752
• Dynamical Evolution and Spatial Mixing of Multiple Population Globular Clusters
• Hubble Space Telescope reveals multiple Sub-Giant Branch in eight Globular Clusters
• Abundances of Cu and Zn in metal-poor stars: clues for Galaxy evolution
• Improved Laboratory Transition Probabilities for Ce II, Application to the Cerium Abundances of the Sun and Five r-process Rich, Metal-Poor Stars, and Rare Earth Lab Data
• New Hubble Space Telescope Observations of Heavy Elements in Four Metal-Poor Stars
• s-Process in Low Metallicity Stars. I. Theoretical Predictions
• M22: A [Fe/H] Abundance Range Revealed
• Secondary star formation within massive star clusters: Origin of multiple stellar populations in globular clusters
• HST Observations of Heavy Elements in Metal-Poor Galactic Halo Stars
• Modelling self-pollution of globular clusters from AGB stars
• Stellar mass and age determinations - I. Grids of stellar models from Z=0.006 to 0.04 and M=0.5 to 3.5 Msun
• Abundances for a large sample of red giants in NGC 1851: hints for a merger of two clusters?
• High resolution spectroscopy of metal rich giants in omega Cen: first indication of SNe Ia enrichment
• NLTE analysis of Sr lines in spectra of late-type stars with new R-matrix atomic data
• Heavy Element Nucleosynthesis in the Brightest Galactic Asymptotic Giant Branch stars
• The Helium content of Globular Clusters: light element abundance correlations and HB morphology. I. NGC6752
• Improved Laboratory Transition Probabilities for Er II and Applications to the Erbium Abundances of the Sun and Five r-Process Rich, Metal-Poor Stars
• Heavy element abundances in giant stars of the globular clusters M4 and M5
• The Evolution of Copper in the Globular Cluster Omega Centauri
• NGC 362: another globular cluster with a split red giant branch
• The extreme chemistry of multiple stellar populations in the metal-poor globular cluster NGC 4833
• New Abundance Determinations of Cadmium, Lutetium, and Osmium in the r-process Enriched Star BD+173248
• On the origin of the stellar halo and multiple stellar populations in the globular cluster NGC 1851
• Ba & Eu Abundances in M15 giant stars
• Nucleosynthesis of s-elements in zero-metal AGB stars
• Non-LTE effects on the lead and thorium abundance determinations for cool stars
• A Comparison of Copper Abundances in Globular Cluster and Halo Field Giant Stars
• Rubidium and lead abundances in giant stars of the globular clusters M4 and M5
• Characterizing the Heavy Elements in Globular Cluster M22 and an Empirical s-process Abundance Distribution Derived from the Two Stellar Groups
• Contrasting copper evolution in Omega Centauri and the Milky Way
• Detection of the Second r-process Peak Element Tellurium in Metal-Poor Stars
• Neutron-capture elements in the metal-poor globular cluster M15
• Homogeneous Metallicities and Radial Velocities for Galactic Globular Clusters
• A Survey of CN and CH Variations in Galactic Globular Clusters from SDSS Spectroscopy
• Towards a working model for the abundance variations within Globular Clusters stars
• Rubidium and lead abundances in giant stars of the globular clusters M 13 and NGC 6752
• NGC 5824: a luminous outer halo globular cluster with an intrinsic abundance spread
• The double RGB in M 2: C, N, Sr and Ba abundances
• Chemical enrichment mechanisms in Omega Centauri: clues from neutron-capture elements
• Modeling the chemical evolution of Omega Centauri using three-dimensional hydrodynamical simulations
• Terzan 5: an alternative interpretation for the split horizontal branch
• From the CMD of Omega Centauri and (super-)AGB stellar models to a Galactic plane passage gas purging chemical evolution scenario
• Carbon and nitrogen abundances of stellar populations in the globular cluster M 2

Cited by in corpus (110)

• Multiple Stellar Populations in Globular Clusters
• A catalogue of masses, structural parameters and velocity dispersion profiles of 112 Milky Way globular clusters
• Near-Field Cosmology with Metal-Poor Stars
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. I. Overview of the Project and Detection of Multiple Stellar Populations
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. IX. The Atlas of Multiple Stellar Populations
• What is a globular cluster? An observational perspective
• A unique model for the variety of multiple populations formation(s) in globular clusters: a temporal sequence
• Evolution and nucleosynthesis of asymptotic giant branch stellar models of low metallicity
• Iron and s-elements abundance variations in NGC5286: comparison with anomalous globular clusters and Milky Way satellites
• Homogeneous Analysis of Globular Clusters from the APOGEE Survey with the BACCHUS Code. II. The Southern Clusters and Overview
• Exploring Anticorrelations and Light Element Variations in Northern Globular Clusters Observed by the APOGEE Survey
• The Gaia-ESO Survey. Mg-Al anti-correlation in iDR4 globular clusters
• Disrupted Globular Clusters Can Explain the Galactic Center Gamma Ray Excess
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. II. The seven stellar populations of NGC7089 (M2)
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XIX. A Chemical Tagging of the Multiple Stellar Populations Over the Chromosome Maps
• Ceci n'est pas a globular cluster: the metallicity distribution of the stellar system Terzan 5
• Multiple populations in globular clusters and their parent galaxies
• A homogeneous analysis of globular clusters from the APOGEE survey with the BACCHUS code. I. The Northern clusters
• Chemical tagging in the SDSS-III/APOGEE survey: new identifications of halo stars with globular cluster origins
• Multiple stellar populations in Magellanic Cloud clusters. III. The first evidence of an extended main sequence turn-off in a young cluster: NGC1856
• Nitrogen abundances and multiple stellar populations in the globular clusters of the Fornax dSph
• A Spectroscopic Analysis of the Galactic Globular Cluster NGC 6273 (M19)
• CNO abundances in the globular clusters NGC 1851 and NGC 6752
• Rotating Stellar Models Can Account for the Extended Main Sequence Turnoffs in Intermediate Age Clusters
• The Accreted Nuclear Clusters of the Milky Way
• First evidence of fully spatially mixed first and second generations in globular clusters: the case of NGC 6362
• A chemical trompe-l'œil: no iron spread in the globular cluster M22
• NLTE Chemical abundances in Galactic open and globular clusters
• The halo+cluster system of the Galactic globular cluster NGC1851
• The Outer Envelopes of Globular Clusters. I. NGC 7089 (M2)
• NGC 6535: the lowest mass Milky Way globular cluster with a Na-O anti-correlation? Cluster mass and age in the multiple population context
• GRACES observations of young [alpha/Fe]-rich stars
• Palomar 5 and its Tidal Tails: A Search for New Members in the Tidal Stream
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. IV. Helium content and relative age of multiple stellar populations within NGC 6352
• Manganese Indicates a Transition from Sub- to Near-Chandrasekhar Type Ia Supernovae in Dwarf Galaxies
• Lithium abundances in globular cluster giants: NGC 1904, NGC 2808, and NGC 362
• The origin of the spurious iron spread in the globular cluster NGC 3201
• Detailed Chemical Abundances in NGC 5824: Another Metal-Poor Globular Cluster with Internal Heavy Element Abundance Variations
• The mosaic multiple stellar populations in $\omega$ Centauri : the Horizontal Branch and the Main Sequence
• Constraints on the Distance Moduli, Helium and Metal Abundances, and Ages of Globular Clusters from their RR Lyrae and Non-Variable Horizontal-Branch Stars. I. M3, M15, and M92
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters - XII. The RGB Bumps of multiple stellar populations
• A Chemical Composition Survey of the Iron-Complex Globular Cluster NGC 6273 (M 19)
• Detection of a population of carbon-enhanced metal-poor stars in the Sculptor dwarf spheroidal galaxy
• Multiple stellar populations and their evolution in globular clusters: A nucleosynthesis perspective
• Heavy elements Ba, La, Ce, Nd, and Eu in 56 Galactic bulge red giants
• Metallicity variations in the Type II globular cluster NGC6934
• Constraints on the distance moduli, helium and metal abundances, and ages of globular clusters from their RR Lyrae and non-variable horizontal-branch stars. II. Multiple stellar populations in 47Tuc, M3, and M13
• Multiple stellar populations in the globular cluster M3 (NGC 5272): a Strömgren perspective
• Low-resolution Spectroscopy for the Globular Clusters with Signs of Supernova Enrichment: M22, NGC 1851 and NGC 288
• Diagnostics of Stellar Modelling from Spectroscopy and Photometry of Globular Clusters
• Detailed Abundances of 15 Stars in the Metal-Poor Globular Cluster NGC 4833
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters - XIV. Multiple stellar populations within M 15 and their radial distribution
• Purveyors of fine halos. II. Chemodynamical association of halo stars with Milky Way globular clusters
• A view of the H-band light-element chemical patterns in Globular Clusters under the AGB self-enrichment scenario
• The complex stellar system M 22: confirming abundance variations with high precision differential measurements
• Chemical Complexity in the Eu-enhanced Monometallic Globular Cluster NGC 5986
• Gaia and Hubble unveil the kinematics of stellar populations in the Type II globular clusters ω Centauri and M 22
• No evidence for multiple stellar populations in the low-mass Galactic globular cluster E 3
• A stellar census in globular clusters with MUSE -- Extending the CaT-metallicity relation below the horizontal branch and applying it to multiple populations
• Spectroscopy and photometry of the least-massive Type-II globular clusters: NGC1261 AND NGC6934
• The iron dispersion of the globular cluster M 2, revised
• The Most Metal-poor Stars in Omega Centauri (NGC 5139)
• Hubble Space Telescope analysis of stellar populations within the globular cluster G1 (Mayall II) in M31
• The chemical composition of NGC5824, a globular cluster without iron spread but with an extreme Mg-Al anticorrelation
• Catalog of Chromium, Cobalt, and Nickel Abundances in Globular Clusters and Dwarf Galaxies
• Confirmation of a metallicity spread amongst first population stars in globular clusters
• Light and Heavy Element Abundance Variations in the Outer Halo Globular Cluster NGC 6229
• The Gaia-ESO Survey: Detailed Abundances in the Metal-poor Globular Cluster NGC 4372
• Globular cluster formation with multiple stellar populations from hierarchical star cluster complexes
• The s-Process Enrichment of the Globular Clusters M4 and M22
• Are the globular clusters with significant internal [Fe/H] spreads all former dwarf galaxy nuclei?
• Excess of Ca (and Sc) produced in globular cluster multiple populations: a first census in 77 Galactic globular clusters
• Is the Young Star RZ Piscium Consuming Its Own (Planetary) Offspring?
• Confirming the intrinsic abundance spread in the globular cluster NGC 6273 (M 19) with calcium triplet spectroscopy
• Decoding the compositions of four bright $r$-process-enhanced stars
• Light Element Discontinuities Suggest an Early Termination of Star Formation in the Globular Cluster NGC 6402 (M14)
• The Chemical Composition of Red Giant Branch Stars in the Galactic Globular Clusters NGC 6342 and NGC 6366
• The CN-CH positive correlation in the globular cluster NGC 5286
• NGC 1261: an $r$-process enhanced globular cluster from the Gaia-Enceladus event
• A chromosome map to unveil stellar populations with different magnesium abundances. The case of Omega Centauri
• Peeking beneath the precision floor I: metallicity spreads and multiple elemental dispersions in the globular clusters NGC 288 and NGC 362
• A chemical signature from fast-rotating low-metallicity massive stars: ROA 276 in omega Centauri
• New cluster members and halo stars of the Galactic globular cluster NGC 1851
• Star formation within globular clusters:discrete multiple bursts and top-light mass functions
• Stellar populations in star clusters
• Nuclei of dwarf spheroidal galaxies KKs3 and ESO269-66 and their counterparts in our Galaxy
• How many explosions does one need? -- Quantifying supernovae in globular clusters from iron abundance spreads
• An outer shade of Pal: Abundance analysis of the outer halo globular cluster Palomar 13
• The Massive M31 Cluster G1: Detailed Chemical Abundances from Integrated Light Spectroscopy
• Spatial and kinematic segregation in star cluster merger remnants
• A comparative study of two 47 Tuc giant stars with different s-process enrichment
• Variability in NGC 3201 giant stars and its impact on their spectroscopic [Fe/H] determination
• Signature of a massive rotating metal-poor star imprinted in the Phoenix stellar stream
• Red Giant Branch Bump Star Counts in Data and Stellar Models
• Trojan globular clusters: radial migration via trapping in bar resonances
• Metallicity of the globular cluster NGC 6388 from high resolution spectra of more than 160 giant stars
• Evidence for Enrichment by Supernovae in the Globular Cluster NGC 6273
• Investigating a predicted metallicity [Fe/H] variation in the Type II Globular Cluster NGC 362
• APOGEE-2S Mg-Al anti-correlation of the Metal-Poor Globular Cluster NGC 2298
• MINCE III. Detailed chemical analysis of the UVES sample
• On the photometric metallicity of Oosterhoff-type I and II RRab stars
• Globular Cluster formation in a collapsing supershell
• Neutron-capture elements in NGC 6752 multiple populations
• The complex stellar system M 22: constraining the chemical enrichment from AGB stars using magnesium isotope ratios
• Hidden Figures of Globular Clusters: Integrated Stellar Populations Impacted by Hot Subdwarfs
• Thirteen facts that you need to know on multiple populations in globular clusters
• Globular Cluster Intrinsic Iron Abundance Spreads: I. Catalog
• Neutron-capture elements in a sample of field metal-poor N-rich dwarfs
• Multiple populations in the Sagittarius nuclear cluster M54 and in other anomalous globular clusters
• A Main Sequence CH-star in the globular cluster M55 (NGC 6809)