Mass Clues in Carbon and Nitrogen: How Red Giants Reveal Their Hidden Histories
Roberts et al. (2026) use asteroseismic masses and [C/N] birth-mass indicators to measure how much mass red giants lose and to identify stars that have likely undergone mass transfer. They find that RGB mass loss decreases with both mass and metallicity, contradicting classical Reimers’ predictions, and propose an adjusted η calibration. They also identify 207 unusual stars whose current masses cannot be explained without past binary interaction.
The Mass-Loss Mystery of Red Supergiants: Investigating Metallicity's Role
The study investigates whether the mass-loss rates of red supergiants (RSGs) depend on metallicity by analyzing thousands of RSGs across multiple galaxies. Results show no strong correlation between metallicity and mass loss, though a "kink" in the mass-loss relation shifts with metallicity. The findings suggest that other factors, like internal turbulence, may drive mass loss rather than metallicity. Future observations, especially with JWST, could clarify remaining uncertainties.