Mass ejections from the rapidly rotating M dwarf star GL 890.
Abstract
Mg II line fluxes from the rapidly rotating single M dwarf Gliese 890 show a 'dip' lasting less than 120 min. H-alpha spectra obtained simultaneously show systematic profile changes during the Mg II 'dip': the line bisector of the H-alpha emission feature shows at first a red then a blue displacement. The behavior of both the H-alpha line bisector and the Mg II emission 'dip' is consistent with a model in which a cloud of mainly neutral hydrogen passes in front of the disk of the star. Similar behavior has been observed in the rapidly rotating single K dwarf AB Doradus. The projected area of the Gl 890 cloud is 0.25-0.40 times that of the stellar disk.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- May 1990
- Bibcode:
- 1990MNRAS.244..291D
- Keywords:
-
- Dwarf Stars;
- M Stars;
- Stellar Mass Ejection;
- Stellar Rotation;
- Companion Stars;
- H Alpha Line;
- Magnesium;
- Stellar Envelopes;
- Stellar Spectrophotometry;
- Astrophysics