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Related papers: Large-scale magnetic topologies of mid-M dwarfs

200 papers

The presence of magnetic fields in O-type stars has been suspected for a long time. The discovery of such fields would explain a wide range of well documented enigmatic phenomena in massive stars, in particular cyclical wind variability, H…

Astrophysics · Physics 2009-11-13 S. Hubrig , M. Schoeller , R. S. Schnerr , J. F. Gonzalez , R. Ignace , H. F. Henrichs

We present magnetic flux measurements in seven rapidly rotating M dwarfs. Our sample stars have X-ray and H-alpha emission indicative of saturated emission, i.e., emission at a high level independent of rotation rate. Our measurements are…

Astrophysics · Physics 2011-02-11 A. Reiners , G. Basri , M. Browning

Aims. The very weak magnetic field detected at the surface of Vega hints at a widespread population of weakly magnetic stars of A and B spectral types. We contribute here to gather more clues about the origin of this magnetism by…

Solar and Stellar Astrophysics · Physics 2022-10-05 P. Petit , T. Böhm , C. P. Folsom , F. Lignières , T. Cang

Accounting for stellar activity is a crucial component of the search for ever-smaller planets orbiting stars of all spectral types. We use Doppler imaging methods to demonstrate that starspot induced radial velocity variability can be…

Solar and Stellar Astrophysics · Physics 2017-01-18 J. R. Barnes , S. V. Jeffers , G. Anglada-Escude , C. A. Haswell , H. R. A. Jones , M. Tuomi , F. Feng , J. S. Jenkins , P. Petit

The rapidly oscillating Ap stars are of importance for studying the atmospheric structure of stars where the process of chemical element diffusion is significant. We have performed a survey for rapid oscillations in a sample of 9 luminous…

Astrophysics · Physics 2009-11-13 L. M. Freyhammer , D. W. Kurtz , M. S. Cunha , G. Mathys , V. G. Elkin , J. D. Riley

Early-type B stars with strong magnetic fields and rapid rotation form centrifugal magnetospheres (CMs), as the relatively weak stellar wind becomes magnetically confined and centrifugally supported above the Kepler co-rotation radius. CM…

Solar and Stellar Astrophysics · Physics 2023-06-28 I. D. Berry , M. E. Shultz , S. P. Owocki , A. ud-Doula

Zeeman Doppler imaging has successfully mapped the large-scale magnetic fields of stars over a large range of spectral types, rotation periods and ages. When observed over multiple epochs, some stars show polarity reversals in their global…

Zeeman-Doppler imaging studies have revealed the complexity of the large-scale magnetic fields of accreting pre-main-sequence stars. All have multipolar magnetic fields with the octupole component being the dominant field mode for many of…

Solar and Stellar Astrophysics · Physics 2016-09-02 Scott G. Gregory , Jean-François Donati , Gaitee A. J. Hussain

We update the status of the spectropolarimetric campaign dedicated to characterise the magnetic field properties of a sample of known exoplanet-hosting stars included in the current target list of the $Ariel$ mission. We analysed…

From our radio continuum and polarization observations of a sample of spiral galaxies with different morphological types, inclinations, and star formation rates (SFR) we found that galaxies with low SFR have higher thermal fractions/…

Astrophysics · Physics 2008-06-13 Marita Krause

Aims. We aim to investigate the long-term temporal evolution of the magnetic field of the solar-type star \xi Bootis A, both from direct magnetic field measurements and from the simultaneous estimate of indirect activity indicators.…

We investigate the magnetic geometry of the active G8 dwarf xi Bootis A, from spectropolarimetric observations obtained in 2003 with the MuSiCoS echelle spectropolarimeter at the Telescope Bernard Lyot (Observatoire du Pic du Midi, France).…

Magnetic A stars represent about $5\%$ of the upper main sequence stars and exhibit highly ordered, very stable and often very strong magnetic fields. They frequently show both, brightness- and spectral line profile variations synchronised…

Solar and Stellar Astrophysics · Physics 2014-02-19 Theresa Lueftinger

We obtained thirteen spectropolarimetric observations of the strongly magnetic rapidly oscillating Ap star HD154708 over three months with the multi-mode instrument FORS1, installed at the 8-m Kueyen telescope of the VLT. These observations…

Solar and Stellar Astrophysics · Physics 2015-05-13 S. Hubrig , G. Mathys , D. W. Kurtz , M. Schoeller , V. G. Elkin , H. F. Henrichs

We present the analysis performed on spectropolarimetric data of 97 O-type targets included in the framework of the MiMeS (Magnetism in Massive Stars) Survey. Mean Least-Squares Deconvolved Stokes I and V line profiles were extracted for…

Core convection and dynamo activity deep within rotating A-type stars of 2 solar masses are studied with 3--D nonlinear simulations. Our modeling considers the inner 30% by radius of such stars, thus capturing within a spherical domain the…

Astrophysics · Physics 2008-11-26 Allan Sacha Brun , Matthew K. Browning , Juri Toomre

Spectropolarimetric observations have been used to map stellar magnetic fields, many of which display strong bands of azimuthal fields that are toroidal. A number of explanations have been proposed to explain how such fields might be…

We performed kinematic studies of the evolution of small-scale magnetic fields in the surface laters of M-dwarfs. We solved the induction equation for a prescribed velocity field, magnetic Reynolds number, and boundary conditions in a…

Astrophysics · Physics 2009-11-07 S. B. F. Dorch , H. -G. Ludwig

We report the discovery of a medium-strength (~0.5kG) magnetic field on the young, massive star tauSco (B0.2V), which becomes the third-hottest magnetic star known. Circularly polarized Zeeman signatures are clearly detected in observations…

This review discusses the problem of reconstruction of surface magnetic field topologies of early-type stars with a focus on mapping methods utilising information content of high-resolution spectropolarimetric observations. Basic principles…

Solar and Stellar Astrophysics · Physics 2019-12-17 Oleg Kochukhov