We present here the final results of the first spectropolarimetric survey of a small sample of active M dwarfs, aimed at providing observational constraints on dynamo action on both sides of the full-convection threshold (spectral type M4). Our two previous studies were focused on early and mid M dwarfs. The present paper examines 11 fully convective late M dwarfs (spectral types M5-M8). Tomographic imaging techniques were applied to time-series of circularly polarized profiles of six stars, in order to infer their large-scale magnetic topologies. For three other stars we could not produce such magnetic maps, because of low variability of the Stokes V signatures, but were able to derive some properties of the magnetic fields.
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- October 2010
- Astrophysics - Solar and Stellar Astrophysics
- 26 pages, 16 figures, 9 tables, 11 tables in appendix. Accepted for publication in MNRAS