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This content will become publicly available on June 1, 2026

Title: A JWST project on 47 Tucanae: Kinematics, energy equipartition, and anisotropy of multiple populations
Recent work withJWSThas demonstrated its capability to identify and chemically characterize multiple populations in globular clusters down to the H-burning limit. In this study, we explore the kinematics of multiple populations in the globular cluster 47 Tucanae by combining data fromJWST, HST, Gaia, and ground-based telescopes. We analyzed velocity dispersion and anisotropy profiles from the cluster center out to ∼10Rh. Our findings indicate that while first population (1G) stars’ motions are isotropic, second population (2G) stars’ motions are significantly radially anisotropic. These results align with the predictions of simulations of the dynamical evolution of clusters where 2G stars are initially more centrally concentrated than 1G stars. Furthermore, we subdivided the 2G population into two subpopulations: 2GAand 2GB, with the latter being more chemically extreme. We compared their dynamical profiles and found no significant differences. For the first time, we measured the degree of energy equipartition among the multiple populations of 47 Tucanae. Overall, within the analyzed radial range (∼2–4Rh), both populations exhibit a low degree of energy equipartition. The most significant differences between 1G and 2G stars are observed in the tangential velocity component, where 2G stars are characterized by a stronger degree of energy equipartition than 1G stars. In the radial component, the behavior of 1G and 2G stars is more variable, with differences largely dependent on radius. Moreover, our analysis reveals that the ratio of rotational velocity to velocity dispersion is larger for the 2G population. Finally, we found that 1G stars exhibit a higher skewness in their tangential proper motions than 2G stars, providing additional evidence of kinematic differences between the two stellar generations.  more » « less
Award ID(s):
2009193
PAR ID:
10626406
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Astronomy and Astrophysics
Date Published:
Journal Name:
Astronomy & Astrophysics
Volume:
698
ISSN:
0004-6361
Page Range / eLocation ID:
A209
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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