Large-scale magnetic topologies of early M dwarfs

@article{Donati2008LargescaleMT,
  title={Large-scale magnetic topologies of early M dwarfs},
  author={J.-F. Donati and Julien Morin and P. Petit and Xavier Delfosse and Thierry Forveille and Michel Auri{\`e}re and R{\'e}mi Cabanac and Boris Dintrans and R Fares and Thomas Gastine and M Jardine and François Ligni{\`e}res and Fr{\'e}d{\'e}ric Paletou and J. C. Ram{\'i}rez V{\'e}lez and Sylvie Th'eado},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2008},
  volume={390},
  pages={545-560}
}
We present here additional results of a spectropolarimetric survey of a small sample of stars ranging from spectral type M0 to M8 aimed at investigating observationally how dynamo processes operate in stars on both sides of the full convection threshold (spectral type M4). The present paper focuses on early M stars (M0-M3), that is above the full convection threshold. Applying tomographic imaging techniques to time series of rotationally modulated circularly polarized profiles collected with… Expand
Large-scale magnetic topologies of late M dwarfs★: Magnetic topologies of late M dwarfs
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 theExpand
Large-scale magnetic fields of low-mass dwarfs: the many faces of dynamo
  • J. Donati
  • Physics
  • Proceedings of the International Astronomical Union
  • 2010
Abstract Magnetic field are ubiquitous to low-mass stars and can potentially impact their evolution and their internal structure; yet the physical processes (called dynamo) that succeed at generatingExpand
MAGNETIC FIELD TOPOLOGY IN LOW-MASS STARS: SPECTROPOLARIMETRIC OBSERVATIONS OF M DWARFS*
The magnetic field topology plays an important role in the understanding of stellar magnetic activity. While it is widely accepted that the dynamo action present in low-mass partially convectiveExpand
What controls the magnetic geometry of M dwarfs
Context: observations of rapidly rotating M dwarfs show a broad variety of large-scale magnetic fields encompassing dipole-dominated and multipolar geometries. In dynamo models, the relativeExpand
Exploring the magnetic field complexity in M dwarfs at the boundary to full convection
Context. Magnetic fields play a pivotal role in the formation and evolution of low-mass stars, but the dynamo mechanisms generating these fields are poorly understood. Measuring cool star magnetismExpand
The evolution of surface magnetic fields in young solar-type stars – I. The first 250 Myr
The surface rotation rates of young solar-type stars vary rapidly with age from the end of the pre-main sequence through the early main sequence. Important changes in the dynamos operating in theseExpand
Starspot distributions on fully convective M dwarfs : implications for radial velocity planet searches
Since M4.5–M9 dwarfs exhibit equatorial rotation velocities of the order of 10 km s −1 on average, radial velocity surveys targeting this stellar population will likely need to find methods toExpand
Magnetic fields of low-mass stars & protostars. Observations & results
Magnetic field are ubiquitous to young and mature low-mass stars, and can potentially impact their formation, their evolution and their internal structure; yet the physical processes that succeed atExpand
Observations of non-solar-type dynamo processes in stars with shallow convective zones★
The magnetic field topology and differential rotation are fundamental signatures of the dynamo processes that generate the magnetic activity observed in the Sun and solar-type stars. To investigateExpand
Exploring the magnetic topologies of cool stars
Abstract Magnetic fields of cool stars can be directly investigated through the study of the Zeeman effect on photospheric spectral lines using several approaches. With spectroscopic measurement inExpand
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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 theExpand
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From observations collected with the ESPaDOnS spectropolarimeter, we report the discovery of magnetic fields at the surface of the mildly accreting classical T Tauri star V2129 Oph. Zeeman signaturesExpand
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TLDR
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I present radio observations of 90 dwarf stars and brown dwarfs of spectral type M5-T8. Three sources exhibit radio activity, in addition to the six objects previously detected in quiescence andExpand
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