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相关论文: A DZ white dwarf with a 30 MG magnetic field

200 篇论文

Magnetic fields with strengths ranging from 300 to 500 kG have recently been discovered in a group of four extremely similar helium-enriched hot subdwarf (He-sdO) stars. Besides their strong magnetic fields, these He-sdO stars are…

太阳与恒星天体物理 · 物理学 2024-11-13 M. Dorsch , C. S. Jeffery , A. Philip Monai , C. A. Tout , E. J. Snowdon , I. Monageng , L. J. A. Scott , B. Miszalski , V. M. Woolf

There are no known examples of magnetic white dwarfs with fields larger than about 3MG paired with a non-degenerate companion in detached binary systems. The suggestion is that highly magnetic, isolated white dwarfs may originate from stars…

太阳与恒星天体物理 · 物理学 2016-01-18 Lilia Ferrario

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…

天体物理学 · 物理学 2007-05-23 Susanne Friedrich , Stefan Jordan , Detlev Koester

The origin of magnetic fields in white dwarfs (WDs) remains mysterious. Magnetic WDs are traditionally associated with field strengths $\gtrsim1\,\mathrm{MG}$, set by the sensitivity of typical spectroscopic magnetic field measurements.…

太阳与恒星天体物理 · 物理学 2025-01-30 Nicholas Z. Rui , Jim Fuller , J. J. Hermes

The latest Gaia data release provides low-resolution spectra for approximately 100 000 white dwarfs. Though useful for pre-classification, they lack the resolution required for accurate spectral type and parameter determination, motivating…

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…

天体物理学 · 物理学 2007-05-23 S. Jordan , P. Schmelcher , W. Becken , W. Schweizer

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…

太阳与恒星天体物理 · 物理学 2023-02-01 François Hardy , Patrick Dufour , Stefan Jordan

When the accreting white dwarf in a magnetic cataclysmic variable star (mCV) has a field strength in excess of 10 MG, it is expected to synchronize its rotational frequency to the binary orbit frequency, particularly at small binary…

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…

We present new photometry and spectroscopy of the 94m eclipsing binary LSQ1725-64 that provide insight into the fundamental parameters and evolutionary state of this system. We confirm that LSQ1725-64 is a magnetic cataclysmic variable…

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…

We report the discovery of a new magnetic DA white dwarf (WD), WD0011-721, which is located within the very important 20pc volume-limited sample of the closest WDs to the Sun. This star has a mean field modulus <|B|> of 343 kG, and from the…

太阳与恒星天体物理 · 物理学 2019-08-07 John D. Landstreet , Stefano Bagnulo

The nature of the excess near-infrared emission associated with the magnetic white dwarf commonly known as SDSS 1212 is investigated primarily through spectroscopy, and also via photometry. The inferred low mass secondary in this system has…

天体物理学 · 物理学 2009-11-13 J. Farihi , M. R. Burleigh , D. W. Hoard

We present the discovery of a magnetic field on the white dwarf component in the detached post common envelope binary (PCEB) CC Cet. Magnetic white dwarfs in detached PCEBs are extremely rare, in contrast to the high incidence of magnetism…

太阳与恒星天体物理 · 物理学 2021-09-08 David J. Wilson , Odette Toloza , John D. Landstreet , Boris T. Gaensicke , Jeremy J. Drake , J. J. Hermes , Detlev Koester

An initial assessment is made of white dwarf and hot subdwarf stars observed in the Sloan Digital Sky Survey. In a small area of sky (190 square degrees), observed much like the full survey will be, 269 white dwarfs and 56 hot subdwarfs are…

We present radio observations of a comprehensive sample of 90 dwarf stars and brown dwarfs ranging from spectral type M5 to T8. We detect three radio active sources in addition to the six objects previously detected in quiescence and…

天体物理学 · 物理学 2008-11-26 Edo Berger

We present a detailed model atmosphere analysis of massive white dwarfs with $M > 0.9~M_\odot$ and $T_{\rm eff}\geq11,000$ K in the Montreal White Dwarf Database 100 pc sample and the Pan-STARRS footprint. We obtained follow-up optical…

Around several single DAZ and DBZ white dwarfs metal-rich disks have been observed, which are mostly believed to originate from disruption of smaller rocky planetesimals. In some cases the material does not (only) form a dusty but gaseous…

太阳与恒星天体物理 · 物理学 2011-06-02 S. Hartmann , T. Nagel , T. Rauch , K. Werner

We report the discovery of a new, polluted, magnetic white dwarf in the Luyten survey of high-proper motion stars. High-dispersion spectra of NLTT 7547 reveal a complex heavy element line spectrum in a cool (~5 200 K) hydrogen-dominated…

太阳与恒星天体物理 · 物理学 2018-11-28 Adela Kawka , Stephane Vennes , Lilia Ferrario , Ernst Paunzen