English
Related papers

Related papers: Kilo-gauss Magnetic Fields in three DA White Dwarf…

200 papers

Following our recent discovery of a new magnetic DQ white dwarf (WD) with CH molecular features, we report the results for the rest of the DQ WDs from our survey. We use high signal-to-noise spectropolarimetric data to search for magnetic…

Solar and Stellar Astrophysics · Physics 2013-08-27 Tommi Vornanen , Svetlana Berdyugina , Andrei Berdyugin

There has been a growing interest within the astrophysics community in highly magnetized and fast-spinning white dwarfs (WDs), commonly referred to as HMWDs. WDs with these characteristics are quite uncommon and possess magnetic fields…

Solar and Stellar Astrophysics · Physics 2024-12-20 M. F. Sousa , E. Otoniel , J. G. Coelho , J. C. N. de Araujo

We study the strongly magnetized white dwarf configurations in a self-consistent manner as a progenitor of the over-luminous type-Ia supernovae. We compute static equilibria of white dwarf stars containing a strong magnetic field and…

Solar and Stellar Astrophysics · Physics 2017-10-25 Prasanta Bera , Dipankar Bhattacharya

M dwarfs are known to generate the strongest magnetic fields among main-sequence stars with convective envelopes, but the link between the magnetic fields and underlying dynamo mechanisms, rotation, and activity still lacks a consistent…

Binary systems containing a magnetic white dwarf and a main-sequence star are considered extremely rare, perhaps non-existent. In the course of a search of magnetic fields in high-mass white dwarfs we have discovered a Sirius-like wide…

Solar and Stellar Astrophysics · Physics 2020-02-12 J. D. Landstreet , S. Bagnulo

Only eleven O-type stars have been confirmed to possess large-scale organized magnetic fields. The presence of a -600G longitudinal magnetic field in the O9.7V star HD54879 with a lower limit of the dipole strength of ~2kG, was discovered a…

Solar and Stellar Astrophysics · Physics 2019-02-19 S. Hubrig , M. Kueker , S. P. Jarvinen , A. F. Kholtygin , M. Schöller , E. B. Ryspaeva , D. D. Sokoloff

We have applied the method of Zeeman tomography to analyze the surface magnetic field structures of the white dwarfs PG 1015+014 and HE 1045-0908 from spin-phase resolved flux and circular polarization spectra obtained with FORS1 at the ESO…

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

In only three of the 61 known magnetic white dwarfs helium has been identified unambiguously while about 20% of all non-magnetic stars of this class are known to contain HeI or HeII. Until recently, data for HeI data were available only for…

Astrophysics · Physics 2009-11-06 S. Jordan , P. Schmelcher , W. Becken

This paper reports circular spectropolarimetry and X-ray observations of several polluted white dwarfs including WD 1145+017, with the aim to constrain the behavior of disk material and instantaneous accretion rates in these evolved…

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

White dwarfs in globular clusters offer additional possibilities to determine distances and ages of globular clusters, provided their spectral types and masses are known. We therefore started a project to obtain spectra of white dwarfs in…

Astrophysics · Physics 2009-11-10 S. Moehler , D. Koester , M. Zoccali , F. R. Ferraro , U. Heber , R. Napiwotzki , A. Renzini

We present an homogeneous analysis of all DA stars labeled as magnetic in the Montreal White Dwarf Database (MWDD). Our sample is restricted to almost all known magnetic white dwarf showing clear sign of splitting ($B \gtrsim$ 1-2 MG) that…

Solar and Stellar Astrophysics · Physics 2023-02-01 François Hardy , Patrick Dufour , Stefan Jordan

We consider a relativistic, degenerate, electron gas under the influence of a strong magnetic field, which describes magnetized white dwarfs. Landau quantization changes the density of states available to the electrons, thus modifying the…

High Energy Astrophysical Phenomena · Physics 2012-11-20 Upasana Das , Banibrata Mukhopadhyay

We present a catalog of 8545 and 19,257 unique DA white dwarfs observed in SDSS Data Release 19 and previous SDSS data releases, respectively. This is the largest catalog of both spectroscopic and photometric measurements of DA white dwarfs…

The nature of the strong absorption features in the white dwarf GD229 has been a real mystery ever since it was found to be magnetic in 1974. All attempts to explain the spectrum by line components of hydrogen failed. With the first sets of…

Astrophysics · Physics 2007-05-23 S. Jordan , P. Schmelcher , W. Becken , W. Schweizer

More than 30% of white dwarfs exhibit atmospheric metals, which are understood to be from recent or ongoing accretion of circumstellar debris. In cool white dwarfs, surface motions should rapidly homogenise photospheric abundances, and the…

Solar and Stellar Astrophysics · Physics 2024-07-25 S. Bagnulo , J. D. Landstreet , J. Farihi , C. P. Folsom , M. A. Hollands , L. Fossati

Massive, highly magnetized white dwarfs with fields up to $10^9$ G have been observed and theoretically used for the description of a variety of astrophysical phenomena. Ultramagnetized white dwarfs with uniform interior fields up to…

Solar and Stellar Astrophysics · Physics 2014-09-29 J. G. Coelho , R. M. Marinho , M. Malheiro , R. Negreiros , D. L. Cáceres , J. A. Rueda , R. Ruffini

This paper intends to give a broad overview of the present knowledge about neutron star magnetic fields, their origin and evolution. An up-to-date overview of the rich phenomenology (encompassing ``classical'' and millisecond radio pulsars,…

Astrophysics · Physics 2007-05-23 Andreas Reisenegger

We report the discovery of two apparently isolated stellar remnants that exhibit rotationally modulated magnetic Balmer emission, adding to the emerging DAHe class of white dwarf stars. While the previously discovered members of this class…

Solar and Stellar Astrophysics · Physics 2023-04-03 Joshua S. Reding , J. J. Hermes , J. C. Clemens , R. J. Hegedus , B. C. Kaiser

Two types of stars are known to have strong, large scale magnetic fields: the main sequence Ap stars and the magnetic white dwarfs. This suggest that the former might be the progenitors of the latter. In order to test this idea, I have…

Astrophysics · Physics 2007-05-23 V. G. Elkin
‹ Prev 1 4 5 6 7 8 10 Next ›