2021/02/24 by M. Tailo, A. P. Milone, E. P. Lagioia +16 · 24 citations
Medicine · Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Blue straggler #Globular cluster #Horizontal branch #Medicine #Metallicity #Photometry (optics) #Physics #Population #Red-giant branch #Star cluster #Star formation #Stars #Stellar evolution #Stellar mass #Stellar population #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stab568
published in Monthly Notices of the Royal Astronomical Society 503(1), 694-703 (Oxford University Press) · 10 pages, 7 figures, 3 tables, accepted for publication on MNRAS
arxiv created 2021/02/24 · openalex publication_date 2021/02/26 · arxiv updated 2021/03/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
ABSTRACT The amount of mass lost by stars during the red-giant branch (RGB) phase is one of the main parameters to understand and correctly model the late stages of stellar evolution. Nevertheless, a fully comprehensive knowledge of the RGB mass-loss is still missing. Galactic Globular Clusters (GCs) are ideal targets to derive empirical formulations of mass-loss, but the presence of multiple populations with different chemical compositions has been a major challenge to constrain stellar masses and RGB mass-losses. Recent work has disentangled the distinct stellar populations along the RGB and the horizontal branch (HB) of 46 GCs, thus providing the possibility to estimate the RGB mass-loss of each stellar population. The mass-losses inferred for the stellar populations with pristine chemical composition (called first-generation or 1G stars) tightly correlate with cluster metallicity. This finding allows us to derive an empirical RGB mass-loss law for 1G stars. In this paper, we investigate seven GCs with no evidence of multiple populations and derive the RGB mass-loss by means of high-precision Hubble-Space Telescope photometry and accurate synthetic photometry. We find a cluster-to-cluster variation in the mass-loss ranging from ∼0.1 to ∼0.3 M⊙. The RGB mass-loss of simple-population GCs correlates with the metallicity of the host cluster. The discovery that simple-population GCs and 1G stars of multiple population GCs follow similar mass-loss versus metallicity relations suggests that the resulting mass-loss law is a standard outcome of stellar evolution.