TESSting Subgiant Physics
Abstract
There are still significant uncertainties in our understand of convection and rotation in evolved low-mass stars. To address this, we have spectroscopically, photometrically, and asteroseismically characterized a set of subgiant and lower red giant stars in the TESS southern continuous viewing zone, and combined them with previous samples from Kepler. I will show that when quantitatively compared, these stars can identify inaccuracies in the temperature and gravity evolution of currently used grids of models. They also show a coherent evolution of the internal rotation rate from the main sequence to the red giant branch and a significant contrast between the core and envelope rotation rates that is incompatible with several proposed theories of angular momentum transport in stellar interiors. Finally, I will end with a discussion of how we can continue to improve our understanding and what these changes mean for future studies of stellar evolution.
- Publication:
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The 20.5th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun (CS20.5)
- Pub Date:
- March 2021
- DOI:
- 10.5281/zenodo.4567718
- Bibcode:
- 2021csss.confE.274T
- Keywords:
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- Post main sequence cool stars