2012/05/17 by Richard B. Stothers · 1 citation
Physics and Astronomy · #Stellar, planetary, and galactic studies #Astronomy and Astrophysical Research #Gamma-ray bursts and supernovae #Physics #Supergiant #Astrophysics #Luminosity #Stars #Convection #Giant star #Astronomy #Envelope (radar) #Hertzsprung–Russell diagram #Red giant #Stellar evolution #Meteorology #Galaxy
paper · doi:10.1088/0004-637x/751/2/151
openalex publication_date 2012/05/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
There is observational evidence that intermittent long secondary periods of ∼1000 days are present in the well-observed yellow hypergiants ρ Cas and HR 8752. The long secondary period is interpreted here as the turnover time of giant convection cells in the convective envelope, as has been already suggested in the case of red giants and supergiants of high luminosity. The observed secondary periods and surface radial velocities of ρ Cas and HR 8752 agree with the theoretical predictions, within the expected errors. These results support a theoretical interpretation that now covers the entire initial mass range from 1 to 50 M ☉ for luminous cool stars.