Multiple Stellar Populations in Globular Clusters with JWST: a NIRCam view of 47 Tucanae

Abstract

We use images collected with the near-infrared camera (NIRCam) on board the James Webb Space Telescope and with the Hubble Space Telescope (HST) to investigate multiple populations at the bottom of the main sequence (MS) of 47 Tucanae. The F115W vs. F115W-F322W2 CMD from NIRCam shows that, below the knee, the MS stars span a wide color range, where the majority of M-dwarfs exhibit blue colors, and a tail of stars are distributed toward the red. A similar pattern is observed from the F160W vs. F110W-F160W CMD from HST, and multiple populations of M-dwarfs are also visible in the optical F606W vs. F606W-F814W CMD. The NIRCam CMD shows a narrow sequence of faint MS stars with masses smaller than 0.1 solar masses. We introduce a chromosome map of M-dwarfs that reveals an extended first population and three main groups of second-population stars. By combining isochrones and synthetic spectra with appropriate chemical composition, we simulate colors and magnitudes of different stellar populations in the NIRCam filters (at metallicities [Fe/H]=-1.5 and [Fe/H]=-0.75) and identify the photometric bands that provide the most efficient diagrams to investigate the multiple populations in globular clusters. Models are compared with the observed CMDs of 47 Tucanae to constrain M-dwarfs' chemical composition. Our analysis suggests that the oxygen range needed to reproduce the colors of first- and second-population M-dwarfs is similar to that inferred from spectroscopy of red giants, constraining the proposal that the chemical variations are due to mass transfer phenomena in proto-clusters.

21 pages, 17 figures, accepted for publication in MNRAS

References in corpus (25)

• The Dartmouth Stellar Evolution Database
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Fast rotating massive stars and the origin of the abundance patterns in galactic globular clusters
• 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
• Spectroscopic and Photometric evidence of two stellar populations in the Galactic Globular Cluster NGC6121 (M4)
• What is a globular cluster? An observational perspective
• Ground-Based CCD Astrometry with Wide Field Imagers. I. [Observations just a few years apart allow decontamination of field objects from members in two Globular clusters.]
• Nitrogen abundances in giant stars of the globular cluster NGC 6752
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XIX. A Chemical Tagging of the Multiple Stellar Populations Over the Chromosome Maps
• Multiple populations in globular clusters and their parent galaxies
• CNO abundances in the globular clusters NGC 1851 and NGC 6752
• Stellar Models of Multiple Populations in Globular Clusters. I. The Main Sequence of NGC 6752
• The HST Large Programme on NGC6752. II. Multiple populations at the bottom of the main sequence probed in NIR
• Multiple stellar populations of globular clusters from homogeneous Ca-Cn photometry. II. M5 (NGC 5904) and a new filter system
• Chemical abundances along the 1G sequence of the chromosome maps: The Globular Cluster NGC 3201
• Multiple stellar populations along the red Horizontal Branch and Red Clump of Globular Clusters
• Survey of multiple populations in globular clusters among very low-mass stars
• Is helium the key parameter in the extended color spread of the first generation stars in M3?
• Chromosome maps of Globular Clusters from wide-field ground-based photometry
• Multiple stellar populations in Asymptotic Giant Branch stars of Galactic Globular Clusters
• Searching for multiple populations in star clusters using the China Space Station Telescope
• Multiple Stellar Populations of Globular Clusters From Homogeneous Ca-CN-CH-NH Photometry. VII. Metal-Poor Populations in 47 Tucanae (NGC 104)
• Models for Metal-Poor Stars with Different Initial Abundances of C, N, O, Mg, and Si. III. Grids of Isochrones for $-2.5\le$ [Fe/H] $\le -0.5$ and Helium Abundances $Y=0.25$ and $0.29$ at Each Metallicity
• The Formation of Globular Clusters as a Case of Overcooling

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• The Small Magellanic Cloud through the lens of the James Webb Space Telescope : binaries and mass function within the galaxy outskirts
• Exploring Multiple Stellar Populations in Globular Clusters with Euclid: A Theoretical Overview and Insights from NGC 6397
• The stellar to sub-stellar masses transition in 47 Tuc
• He-enriched STAREVOL models for globular cluster multiple populations. Self-consistent isochrones from ZAMS to the TP-AGB phase
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