Analysis of the chromosphere and corona of low-activity early-M dwarfs
Abstract
While most of the exoplanets have been found orbiting around solar-type stars, low-mass stars have recently been recognized as ideal exo-life laboratory. Currently, stellar activity is one of the limiting factors for the characterization of Earth-twins and for assessing their habitability: understanding the activity of M dwarfs is thus crucial. In this contribution I present the spectroscopic analysis of the quiet early-M dwarfs monitored within the HADES (HArps-n red Dwarf Exoplanet Survey) radial velocity survey. The spectra allow us to analyze simultaneously the Ca ii H&K doublet and the Hydrogen Balmer series, while the intensive follow up gives us a large number of spectra ( 100) for each target. We complement this dataset with ground-based follow-up photometry and archival X-ray data. I present our results on the activity-rotation-stellar parameters and flux-flux relationships, and discuss the correlation of emission fluxes at low activity levels and the evolution timescales of active regions.
- Publication:
-
Solar and Stellar Magnetic Fields: Origins and Manifestations
- Pub Date:
- 2020
- DOI:
- 10.1017/S1743921319009931
- Bibcode:
- 2020IAUS..354..355S
- Keywords:
-
- stars: activity;
- stars: atmospheres;
- stars: chromospheres;
- stars: coronae;
- stars: late-type;
- stars: low-mass;
- brown dwarfs;
- stars: rotation;
- stars: spots