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Related papers: Weak magnetic fields in white dwarfs and their dir…

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M dwarfs are known to host magnetic fields, impacting exoplanet studies and playing a key role in stellar and planetary formation and evolution. Observations revealed the long-term evolution of the large-scale magnetic field reconstructed…

Solar and Stellar Astrophysics · Physics 2025-08-07 P. I. Cristofari , J. -F. Donati , S. Bellotti , É. Artigau , A. Carmona , C. Moutou , X. Delfosse , P. Petit , B. Finociety , J. Dias do Nascimento

Primordial magnetic fields (PMFs) may significantly influence 21-cm physics via two mechanisms: (i) magnetic heating of the intergalactic medium (IGM) through ambipolar diffusion (AD) and decaying magnetohydrodynamic turbulence (DT), (ii)…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-27 Arko Bhaumik , Debarun Paul , Supratik Pal

Over the past couple of decades, researchers have predicted more than a dozen super-Chandrasekhar white dwarfs from the detections of over-luminous type Ia supernovae. It turns out that magnetic fields and rotation can explain such massive…

General Relativity and Quantum Cosmology · Physics 2021-07-19 Surajit Kalita

Magnetic fields are present in a wide variety of stars throughout the HR diagram and play a role at basically all evolutionary stages, from very-low-mass dwarfs to very massive stars, and from young star-forming molecular clouds and…

Solar and Stellar Astrophysics · Physics 2010-01-15 JF Donati , JD Landstreet

Magnetic fields in cool stars can be investigated by measuring Zeeman line broadening and polarization in atomic and molecular lines. Similar to the Sun, these fields are complex and height-dependent. Many molecular lines dominating M-dwarf…

Solar and Stellar Astrophysics · Physics 2019-09-11 N. Afram , S. V. Berdyugina

Sufficiently old white dwarfs cool down through a convective envelope that directly couples their degenerate cores to the surface. Magnetic fields may inhibit this convection by stiffening the criterion for convective instability. We…

Solar and Stellar Astrophysics · Physics 2024-09-13 Sivan Ginzburg

We present a new method for direct measurement of magnetic fields on ultracool stars and brown dwarfs. It takes advantage of the Wing-Ford band of FeH, which are seen throughout the M and L spectral types. These molecular features are not…

Astrophysics · Physics 2009-11-11 Ansgar Reiners , Gibor Basri

We have identified 7 new magnetic DA white dwarfs in the Early Data Release of the Sloan Digital Sky Survey. Our selection strategy has also recovered all the previously known magnetic white dwarfs contained in the SDSS EDR, KUV03292+0035…

Astrophysics · Physics 2009-11-07 B. T. Gaensicke , F. Euchner , S. Jordan

The widely accepted assumption is that metals detected in the spectra of a few cool helium-rich white dwarfs cannot be of primordial origin and therefore must be accreted from the interstellar medium. However, the observed abundances of…

Astrophysics · Physics 2007-05-23 Susanne Friedrich , Stefan Jordan , Detlev Koester

We have measured the surface magnetic flux on four accreting young brown dwarfs and one non-accreting young very low-mass star utilizing high resolution spectra of absorption lines of the FeH molecule. A magnetic field of 1-2 kG had been…

Solar and Stellar Astrophysics · Physics 2011-02-11 Ansgar Reiners , Gibor Basri , Ulrich R. Christensen

The hard X-ray spectrum of magnetic cataclysmic variables can be modelled to provide a measurement of white dwarf mass. This method is complementary to radial velocity measurements, which depend on the (typically rather uncertain) binary…

Low-frequency polarisation observations of pulsars, facilitated by next-generation radio telescopes, provide powerful probes of astrophysical plasmas that span many orders of magnitude in magnetic field strength and scale: from pulsar…

High Energy Astrophysical Phenomena · Physics 2018-08-22 C. Sobey , the LOFAR , MWA collaborations

We have succeeded in obtaining magnetized star models that have extremely strong magnetic fields in the interior of the star. In our formulation, arbitrary functions of the magnetic flux function appear in the expression for the current…

High Energy Astrophysical Phenomena · Physics 2013-04-03 Kotaro Fujisawa , Shin'ichirou Yoshida , Yoshiharu Eriguchi

Magnetic fields are ubiquitous in the universe and an important component of the interstellar medium. It is crucial to accurately model and understand their properties in different environments and across all mass ranges of galaxies to…

Astrophysics of Galaxies · Physics 2025-12-22 Maria Werhahn , Rüdiger Pakmor , Rebekka Bieri , Freeke van de Voort , Rosie Y. Talbot , Volker Springel

We have discovered that the white dwarf PG 2329+267 is magnetic, and assuming a centered dipole structure, has a dipole magnetic field strength of approximately 2.3MG. This makes it one of only approximately 4% of isolated white dwarfs with…

Astrophysics · Physics 2009-10-30 C. Moran , T. R. Marsh , V. S. Dhillon

We have started a systematic study of the field topologies of magnetic single and accreting white dwarfs using Zeeman tomography. Here we report on our analysis of phase-resolved flux and circular polarization spectra of the magnetic…

Astrophysics · Physics 2007-05-23 K. Reinsch , F. Euchner , K. Beuermann , S. Jordan , B. T. Gaensicke

We investigate whether nearby white dwarfs (WDs) can constrain dark matter (DM) interactions with ordinary matter. As experimental sensitivity improves, driven by the Gaia mission, the sample volume of nearby WDs has been increasing over…

High Energy Physics - Phenomenology · Physics 2025-10-28 Pooja Bhattacharjee , Sandra Robles , Stephan A. Meighen-Berger , Francesca Calore

The low-resolution, Cassegrain mounted, FORS spectropolarimeter of the ESO Very Large Telescope is being extensively used for magnetic field surveys. Some of the new discoveries suggest that relatively strong magnetic fields may play an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Stefano Bagnulo , Luca Fossati , Oleg Kochukhov , John D. Landstreet

Previous circular polarization observations obtained with the ESO FOcal Reducer low dispersion spectrograpgh at the VLT in 2007-2008 revealed the presence of a weak longitudinal magnetic field on the surface of the optical component of the…

Solar and Stellar Astrophysics · Physics 2018-12-12 Swetlana Hubrig , Alexander F. Kholtygin , Lara Sidoli , Markus Schöller , Silva P. Jarvinen