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arXiv · 2610.18996

The mass functions of multiple stellar populations in 47 Tucanae

M. Scalco·J. Bruce·E. Vesperini·L. R. Bedin
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Abstract

We used a combination of James Webb Space Telescope (JWST) and Hubble Space Telescope (HST) observations to investigate the mass functions (MFs) of the different stellar populations in the globular cluster (GC) 47 Tucanae (NGC 104) over a wide stellar-mass interval. We identified the multiple populations along the lower main sequence using only JWST photometry and, in particular, colour combinations sensitive to variations in oxygen abundance. We derived the MFs of the first- and second-population (1P and 2P) stars separately and found that in the low-mass regime, the present-day MF of the 1P population is significantly steeper than that of the 2P population, which appears nearly flat. We also present the results of a dynamical model showing that this behaviour requires a different initial mass function (IMF) for the 2P and the 1P populations in the 0.1-0.4 solar masses mass range, thus providing a new fundamental constraint for the study of the star formation of multiple populations in GCs.

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M. Scalco, J. Bruce, E. Vesperini, L. R. Bedin. 2026-10-13. The mass functions of multiple stellar populations in 47 Tucanae. https://doi.org/10.1051/0004-6361%2F202661178

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