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Related papers: Large-scale magnetic topologies of M dwarfs

200 papers

Magnetic fields have been hypothesized to inflate the radii of low-mass stars---defined as less than 0.8 solar masses---in detached eclipsing binaries (DEBs). We evaluate this hypothesis using the magnetic Dartmouth stellar evolution code.…

Solar and Stellar Astrophysics · Physics 2015-06-17 Gregory A. Feiden , Brian Chaboyer

We present results from the volume-complete spectroscopic survey of 0.1-0.3M$_\odot$ M dwarfs within 15pc. This work discusses the active sample without close binary companions, providing a comprehensive picture of these 123 stars with…

Solar and Stellar Astrophysics · Physics 2023-06-28 Emily K Pass , Jennifer G Winters , David Charbonneau , Jonathan M Irwin , Amber A Medina

Magnetic confinement of stellar winds leads to the formation of magnetospheres, which can be sculpted into Centrifugal Magnetospheres (CMs) by rotational support of the corotating plasma. The conditions required for the CMs of magnetic…

The regulation of angular momentum is one of the key processes for our understanding of stellar evolution. In contrast to solar-mass stars, very low mass (VLM) objects and brown dwarfs are believed to be fully convective. This may lead to…

Astrophysics · Physics 2007-05-23 Jochen Eisloeffel , Alexander Scholz

Building on results from the Magnetism in Massive Stars (MiMeS) project, this paper shows how a two-parameter classification of massive-star magnetospheres in terms of the magnetic wind confinement (which sets the Alfv\'en radius RA) and…

Stellar dynamos generate magnetic fields that are of fundamental importance to the variability and evolution of Sun-like and low-mass stars, and for the development of their planetary systems. We report measurements of surface-average…

Many stars evolve into magnetic white dwarfs, and observations may help to understand when the magnetic field appears at the stellar surface, if and how it evolves during the cooling phase, and what are the mechanisms that generate it.…

Solar and Stellar Astrophysics · Physics 2021-10-04 S. Bagnulo , J. D. Landstreet

The rotation-activity connection explains stellar activity in terms of rotation and convective overturn time. It is well established in stars of spectral types F--K and in M-type stars of young clusters. It is not established in field…

Astrophysics · Physics 2009-11-13 Ansgar Reiners

We rediscuss the evolutionary state of upper main sequence magnetic stars using a sample of Ap and Bp stars with accurate Hipparcos parallaxes and definitely determined longitudinal magnetic fields. FORS1 at the VLT in spectropolarimetric…

Astrophysics · Physics 2007-05-23 S. Hubrig , P. North , T. Szeifert

We present the results from a spectroscopic study of 1080 nearby active M dwarfs, selected by correlating the 2MASS and ROSAT catalogs. We have derived the spectral types and estimated distances for all of our stars. The spectral types…

Astrophysics · Physics 2008-11-26 Basmah Riaz , John E. Gizis , James Harvin

Around 10% of white dwarfs exhibit global magnetic structures with fields ranging from 1 kG to hundreds of MG. Recently, the first radiation magnetohydrodynamics simulations of the atmosphere of white dwarfs showed that convection should be…

The Sun and other cool stars harbouring outer convection zones manifest magnetic activity in their atmospheres. The connection between this activity and the properties of a deep-seated dynamo generating the magnetic flux is not well…

Solar and Stellar Astrophysics · Physics 2015-05-27 Emre Işık , Dieter Schmitt , Manfred Schüssler

Magnetic fields are believed to be generated in the cores of massive main sequence stars, and these may survive on to later stages of evolution. Observations of depressed dipole modes in red giant stars have been touted as evidence for…

Solar and Stellar Astrophysics · Physics 2020-03-11 Shyeh Tjing Loi

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 these stars may result from this evolution,…

Solar and Stellar Astrophysics · Physics 2016-01-27 C. P. Folsom , P. Petit , J. Bouvier , A. Lèbre , L. Amard , A. Palacios , J. Morin , J. -F. Donati , S. V. Jeffers , S. C. Marsden , A. A. Vidotto

We performed a highly sensitive search for magnetic fields on a large set of HgMn stars. With the aid of a new polarimeter attached to the HARPS spectrometer at the ESO 3.6m-telescope, we obtained high-quality circular polarization spectra…

Evolutionary models for massive stars, accounting for rotational mixing effects, do not predict any core-processed material at the surface of B dwarfs with low rotational velocities. Contrary to theoretical expectations, we present a…

Astrophysics · Physics 2009-11-13 T. Morel , S. Hubrig , M. Briquet

For main-sequence stars beyond spectral type M5 the characteristics of magnetic activity common to warmer solar-like stars change into the brown-dwarf domain: the surface magnetic field becomes more dipolar and the evolution of the field…

Solar and Stellar Astrophysics · Physics 2011-02-11 C. J. Schrijver

Rotation and magnetism are increasingly recognized as important phenomena in stellar evolution. Surface magnetic fields from a few to $20{,}000\,$G have been observed and models have suggested that magnetohydrodynamic transport of angular…

Solar and Stellar Astrophysics · Physics 2018-04-04 Leo G. Quentin , Christopher A. Tout

Average magnetic field measurements are presented for 62 M-dwarf members of the Pleiades open cluster, derived from Zeeman-enhanced Fe I lines in the H-band. An MCMC methodology was employed to model magnetic filling factors using SDSS-IV…

Stellar magnetic field measurements obtained from spectropolarimetry offer key data for activity and dynamo studies, and we present the results of a major high-resolution spectropolarimetric Bcool project magnetic snapshot survey of 170…