Gaia-ESO Survey: Detailed elemental abundances in red giants of the peculiar globular cluster NGC 1851

Abstract

Context. NGC 1851 is one of several globular clusters for which multiple stellar populations of the subgiant branch have been clearly identified and a difference in metallicity detected. A crucial piece of information on the formation history of this cluster can be provided by the sum of A(C+N+O) abundances. However, these values have lacked a general consensus thus far. The separation of the subgiant branch can be based on age and/or A(C+N+O) abundance differences. Aims. Our main aim was to determine carbon, nitrogen, and oxygen abundances for evolved giants in the globular cluster NGC1851 in order to check whether or not the double populations of stars are coeval. Methods. High-resolution spectra, observed with the FLAMES-UVES spectrograph on the ESO VLT telescope, were analysed using a differential model atmosphere method. Results. We provide abundances of up to 29 chemical elements for a sample of 45 giants in NGC 1851. The investigated stars can be separated into two populations with a difference of 0.07 dex in the mean metallicity, 0.3 dex in the mean C/N, and 0.35 dex in the mean s-process dominated element-to-iron abundance ratios [s/Fe]. No significant difference was determined in the mean values of A(C+N+O) as well as in abundance to iron ratios of carbon, alpha- and iron-peak-elements, and of europium. Conclusions. As the averaged A(C+N+O) values between the two populations do not differ, additional evidence is given that NGC 1851 is composed of two clusters, the metal-rich cluster being by about 0.6 Gyr older than the metal-poor one. A global overview of NGC 1851 properties and the detailed abundances of chemical elements favour its formation in a dwarf spheroidal galaxy that was accreted by the Milky Way.

arXiv comment13 pages, 17 figures, accepted to Astronomy and Astrophysics

References in corpus (87)

• Gaia Data Release 2. Summary of the contents and survey properties
• The Gaia mission
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
• Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
• Multiple Stellar Populations in Globular Clusters
• A catalogue of masses, structural parameters and velocity dispersion profiles of 112 Milky Way globular clusters
• Origin of the system of globular clusters in the Milky Way
• Massive binaries as the source of abundance anomalies in globular clusters
• Non-LTE calculations for neutral Na in late-type stars using improved atomic data
• Thermohaline mixing: A physical mechanism governing the photospheric composition of low-mass giants
• Gaia FGK Benchmark Stars - Metallicity
• Gaia FGK Benchmark Stars: Effective temperatures and surface gravities
• The ACS Survey of Galactic Globular Clusters. III. The Double Subgiant Branch of NGC 1851
• Thermohaline instability and rotation-induced mixing. III - Grid of stellar models and asymptotic asteroseismic quantities from the pre-main sequence up to the AGB for low- and intermediate-mass stars at various metallicities
• Thermohaline instability and rotation-induced mixing. I - Low- and intermediate-mass solar metallicity stars up to the end of the AGB
• What is a globular cluster? An observational perspective
• Chemical Evolution of the Magellanic Clouds: analytical models
• Deep Mixing of He-3: Reconciling Big Bang and Stellar Nucleosynthesis
• Gaia-ESO Survey: The analysis of high-resolution UVES spectra of FGK-type stars
• Concurrent formation of supermassive stars and globular clusters: implications for early self-enrichment
• The two metallicity groups of the globular cluster M22: a chemical perspective
• Stellar Evolution with Rotation and Magnetic Fields IV: The Solar Rotation Profile
• Atomic data for the Gaia-ESO Survey
• The double Subgiant Branch of NGC 1851: the role of the CNO abundance
• The rotationally stabilized VPOS and predicted proper motions of the Milky Way satellite galaxies
• Multiple stellar populations in the globular cluster NGC 1851
• An abundance analysis of bright giants in the globular cluster NGC 1851
• Rotational mixing in low-mass stars : I Effect of the mu-gradients in main sequence and subgiant Pop I stars
• Reverse engineering the Milky Way
• Abundances in giant stars of the globular cluster NGC 6752
• Experimental f-value and isotopic structure for the Ni I line blended with [OI] at 6300A
• Can Extra Mixing in RGB and AGB Stars Be Attributed to Magnetic Mechanisms?
• The Gaia-ESO Survey. Mg-Al anti-correlation in iDR4 globular clusters
• The SUMO project I. A survey of multiple populations in globular clusters
• The Fall of a Giant. Chemical evolution of Enceladus, alias the Gaia Sausage
• Homogeneous photometry VII. Globular clusters in the Gaia era
• A General Abundance Problem for All Self-Enrichment Scenarios for the Origin of Multiple Populations in Globular Clusters
• A large C+N+O abundance spread in giant stars of the globular cluster NGC 1851
• Abundances for a large sample of red giants in NGC 1851: hints for a merger of two clusters?
• Fe I Oscillator Strengths for the Gaia-ESO Survey
• Inferring the Age of the Universe with Globular Clusters
• Constraining Globular Cluster Formation Through Studies of Young Massive Clusters: I. A lack of ongoing star formation within young clusters
• A 500 Parsec Halo Surrounding the Galactic Globular NGC 1851
• Detailed abundances of Red Giants in the Globular Cluster NGC~1851: C+N+O and the Origin of Multiple Populations
• Magnetic Mixing in Red Giant and Asymptotic Giant Branch Stars
• Solar oxygen abundance
• The Gaia-ESO Survey: processing of the FLAMES-UVES spectra
• Gaia EDR3 proper motions of Milky Way dwarfs I: 3D Motions and Orbits
• 3D NLTE spectral line formation of lithium in late-type stars
• Thermohaline mixing in evolved low-mass stars
• Elevated r-process enrichment in Gaia Sausage and Sequoia
• Magneto-Thermohaline Mixing in Red Giants
• CNO abundances in the globular clusters NGC 1851 and NGC 6752
• Low-resolution spectroscopy of main sequence stars belonging to 12 Galactic globular clusters. I. CH and CN band strength variations
• The Outer Envelopes of Globular Clusters. II. NGC 1851, NGC 5824 and NGC 1261
• $R$-process enhancements of Gaia-Enceladus in GALAH DR3
• On the origin of the stellar halo and multiple stellar populations in the globular cluster NGC 1851
• Abundance Anomalies and Rotational Evolution of Low Mass Red Giants: A Maximal Mixing Approach
• The Gaia-ESO survey: impact of extra-mixing on C- and N-abundances of giant stars
• A chemical trompe-l'œil: no iron spread in the globular cluster M22
• The halo+cluster system of the Galactic globular cluster NGC1851
• NLTE Chemical abundances in Galactic open and globular clusters
• The Gaia-ESO Survey: calibration strategy
• The Gaia-ESO Survey: CNO abundances in the open clusters Trumpler 20, NGC 4815, and NGC 6705
• A deep insight into the Mg-Al nucleosynthesis in massive AGBs and SAGB stars
• The Na-O anticorrelation in horizontal branch stars. II. NGC1851
• Oxygen abundance distribution in Galactic disc
• Mergers of Globular Clusters
• Oxygen lines in solar granulation. I. Testing 3D models against new observations with high spatial and spectral resolution
• Spectroscopic Signatures of Extra-Tidal Stars Around the Globular Clusters NGC 6656 (M22), NGC 3201 and NGC 1851 from RAVE
• C and N abundances of MS and SGB stars in NGC 1851
• Light Elements in the Universe
• CNO and F abundances in the globular cluster M22 (NGC 6656)
• Spectroscopic analysis of the two subgiant branches of the globular cluster NGC1851
• The double RGB in M 2: C, N, Sr and Ba abundances
• Homogeneous Analysis of Globular Clusters from the APOGEE Survey with the BACCHUS Code $-$ III. $\omega$ Cen
• Low-resolution Spectroscopy for the Globular Clusters with Signs of Supernova Enrichment: M22, NGC 1851 and NGC 288
• Nucleosynthesis of light element isotopes in evolved stars experiencing extended mixing
• From Canonical to Enhanced Extra Mixing in Low-Mass Red Giants: Tidally Locked Binaries
• On the metallicity distribution of the peculiar globular cluster M22
• A broad perspective on multiple abundance populations in the globular cluster NGC 1851
• Cyanogen in NGC 1851 RGB and AGB Stars: Quadrimodal Distributions
• NGC 1261: an $r$-process enhanced globular cluster from the Gaia-Enceladus event
• New cluster members and halo stars of the Galactic globular cluster NGC 1851
• Five Stellar Populations in M22 (NGC 6656)

Cited by in corpus (6)

• Reconstructing the Disrupted Dwarf Galaxy $Gaia$-Sausage/Enceladus Using its Stars and Globular Clusters
• The complex stellar system M 22: confirming abundance variations with high precision differential measurements
• Multiple Stellar Populations outside the tidal radius of NGC1851 through Gaia DR3 XP Spectra
• Investigating a predicted metallicity [Fe/H] variation in the Type II Globular Cluster NGC 362
• Neutron-Capture Element Signatures in Globular Clusters: Insights from the Gaia-ESO Survey
• Atomic Radiative Data for Oxygen and Nitrogen for Solar Photospheric Studies