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Related papers: Complexity of magnetic fields on red dwarfs

200 papers

A significant fraction of white dwarfs, the degenerate remnants of low- and intermediate-mass stars, host strong magnetic fields; yet, the origin and evolution of these magnetic fields remain poorly understood. Building a large,…

Solar and Stellar Astrophysics · Physics 2026-03-24 Larissa L. Amorim , S. O. Kepler , Alejandra D. Romero

M dwarfs are key targets for high-resolution spectroscopic analyses due to a high incidence of these stars in the solar neighbourhood and their importance as exoplanetary hosts. Several methodological challenges make such analyses…

Solar and Stellar Astrophysics · Physics 2021-06-02 T. Olander , U. Heiter , O. Kochukhov

Observations indicate that magnetic fields on neutron stars span at least the range $10^{8-15}$ G, corresponding to a range of magnetic fluxes similar to that found in white dwarfs and main sequence stars. The observational evidence is…

Astrophysics · Physics 2007-05-23 Andreas Reisenegger

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

Magnetic fields pervade in the interstellar medium (ISM) and are believed to be important in the process of star formation, yet probing magnetic fields in star formation regions is challenging. We propose a new method to use Faraday…

Astrophysics of Galaxies · Physics 2018-06-27 M. Tahani , R. Plume , J. C. Brown , J. Kainulainen

About 20% of the white dwarfs possess a magnetic field that may be detected by the splitting and/or polarization of their spectral lines. As they cool, the effective temperatures of the white dwarfs becomes so low that no spectral lines can…

Solar and Stellar Astrophysics · Physics 2024-08-08 A. Berdyugin , J. D. Landstreet , S. Bagnulo , V. Piirola , S. V. Berdyugina

M dwarf stars are currently the main targets in searches for potentially habitable planets. However, their winds have been suggested to be harmful to planetary atmospheres. Here, in order to better understand the winds of M dwarfs and also…

Solar and Stellar Astrophysics · Physics 2020-04-01 Amanda Mesquita , Aline Vidotto

A significant fraction of white dwarfs possess a magnetic field with strengths ranging from a few kG up to about 1000 MG. However, the incidence of magnetism varies when the white dwarf population is broken down into different spectral…

Solar and Stellar Astrophysics · Physics 2020-10-14 Adela Kawka

We report here our spectropolarimetric observations obtained using the Espadons/CFHT high resolution spectrograph of two M dwarf stars which standard models suggest are fully convective: EV Lac (M3.5) and HH And (M5.5). The difference in…

Astrophysics · Physics 2009-11-11 N. Phan-Bao , E. L. Martin , J. -F Donati , J. Lim

Besides their own intrinsic interest, correct interpretation of solar surface magnetic field observations is crucial to our ability to describe the global magnetic structure of the solar atmosphere. Photospheric magnetograms are often used…

Solar and Stellar Astrophysics · Physics 2010-10-29 Gordon J. D. Petrie , Irina Patrikeeva

Linearly polarized emission from dust grains and molecular spectroscopy is an effective probe of the magnetic field topology in the interstellar medium and molecular clouds. The longstanding Davis-Chandrasekhar-Fermi (DCF) method and the…

Astrophysics of Galaxies · Physics 2022-09-13 Junhao Liu , Qizhou Zhang , Keping Qiu

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).…

Solar and Stellar Astrophysics · Physics 2010-06-28 J. Morin , J. F. Donati , P. Petit , X. Delfosse , T. Forveille , M. M. Jardine

The long-term magnetic behavior of objects near the cooler end of the stellar main sequence is poorly understood. Most theoretical work on the generation of magnetism in these ultracool dwarfs (spectral type >=M7 stars and brown dwarfs)…

Solar and Stellar Astrophysics · Physics 2016-10-19 Matthew Route

A multi-line Bayesian analysis of the Zeeman broadening in the solar atmosphere is presented. A hierarchical probabilistic model, based on the simple but realistic Milne-Eddington approximation to the solution of the radiative transfer…

Solar and Stellar Astrophysics · Physics 2015-06-18 A. Asensio Ramos

Recent high-angular-resolution (up to 0.7") dust polarization observations toward star forming regions are summarized. With the Sub-Millimeter Array, the emission from the dense structures is traced and resolved. The detected magnetic field…

Astrophysics of Galaxies · Physics 2012-02-22 Ya-Wen Tang , Patrick M. Koch , Paul T. P. Ho

The configuration and evolution of the magnetic field in star-forming cores are investigated in order to directly compare simulations and observations. We prepare four different initial clouds having different magnetic field strengths and…

Solar and Stellar Astrophysics · Physics 2015-06-11 Akimasa Kataoka , Masahiro N. Machida , Kohji Tomisaka

The presence of a strong magnetic field is a feature common to a significant fraction of degenerate stars, yet little is understood about field origin and evolution. New observational constraints from volume-limited surveys point to a more…

Solar and Stellar Astrophysics · Physics 2022-08-24 Stefano Bagnulo , John D. Landstreet

With the recent advent of circular polarization capabilities at the Atacama Large Millimeter/submillimeter Array (ALMA), Zeeman effect measurements of spectral lines are now possible as a means to directly probe line-of-sight magnetic…

Solar and Stellar Astrophysics · Physics 2020-11-04 Renato Mazzei , L. Ilsedore Cleeves , Zhi-Yun Li

With only a handful of known magnetic massive stars, there is a troubling deficit in the scope of our knowledge of the influence of magnetic fields on stellar evolution, and almost no empirical basis for understanding how fields modify mass…

Solar and Stellar Astrophysics · Physics 2011-08-15 J. H. Grunhut , G. A. Wade , the MiMeS Collaboration

Despite the ubiquity of M dwarfs and their growing importance to studies of exoplanets, Galactic evolution, and stellar structure, methods for precisely measuring their fundamental stellar properties remain elusive. Existing techniques for…

Solar and Stellar Astrophysics · Physics 2015-06-24 Ryan C. Terrien , Suvrath Mahadevan , Chad F. Bender , Rohit Deshpande , Paul Robertson