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Related papers: Spectra of accretion discs around white dwarfs

200 papers

Models of Soft X--ray Transients are presented and compared with observations. The importance of inner advection--dominated flows in quiescent transient sources is discussed, as well as the problem of global stability of the standard outer…

Astrophysics · Physics 2016-01-27 J. P. Lasota

Rather than accreting via a disk, some White Dwarfs (WDs) in quiescent Dwarf Novae (DN) could accrete via an Advection-Dominated Accretion Flow (ADAF) possibly responsible for the X-ray Bremsstrahlung emission observed. Such a hot accretion…

Astrophysics · Physics 2009-10-31 Kristen Menou , Rosalba Perna , John Raymond

Diversity of the X-ray observations of dwarf nova are still not fully understood. I review the X-ray spectral characteristics of dwarf novae during the quiescence in general explained by cooling flow models and the outburst spectra that…

High Energy Astrophysical Phenomena · Physics 2014-03-19 S. Balman

Light curve analysis of decay phase of nova outburst are summarized. Nova duration is determined by the strong wind mass-loss which depends only on the white dwarf mass. Fast novae correspond very massive white dwarfs and very slow novae…

Astrophysics · Physics 2007-05-23 Mariko Kato

White dwarfs (WDs) are the final fate of about 97\% of the stars in our galaxy, making them vital tracers of stellar history. A fraction of WDs exist in cataclysmic variable (CV) systems, accreting matter from a nearby companion star. A…

Solar and Stellar Astrophysics · Physics 2026-03-02 Praphull Kumar , Dean M. Townsley , Hunter Anz

We study the power spectra of the variability of seven intermediate polars containing magnetized asynchronous accreting white dwarfs, XSS J00564+4548,IGR J00234+6141, DO Dra, V1223 Sgr, IGR J15094-6649, IGR J16500-3307 and IGR J17195-4100,…

The accretion of planetary debris into the atmospheres of white dwarfs leads to the presence of metal lines in their spectra. Cool metal-rich white dwarfs, which left the main-sequence many Gyr ago, allow the study of the remnants of the…

Solar and Stellar Astrophysics · Physics 2022-01-05 Mark A. Hollands , Pier-Emmanuel Tremblay , Boris T. Gänsicke , Detlev Koester

Spectra of Seyfert Is are commonly modelled as emission from an X-ray illuminated flat accretion disc orbiting a central black hole. This provides both a reprocessed and direct component of the X-ray emission as required by observations of…

Astrophysics · Physics 2009-10-31 Eric G. Blackman

Context. The disc instability model (DIM) successfully explains why many accreting compact binary systems exhibit outbursts, during which their luminosity increases by orders of magnitude. The DIM correctly predicts which systems should be…

High Energy Astrophysical Phenomena · Physics 2017-04-12 J. -M. Hameury , J. -P. Lasota , C. Knigge , E. G. Körding

We present the results of a multi-component synthetic spectral analysis of the archival far ultraviolet spectra of several key nova-like variables including members of the SW Sex, RW Tri, UX UMa and VY Scl subclasses: KR Aur, RW Tri, V825…

We describe the results of numerical simulations of the dynamics of the boundary layer (BL) between the accretion disk and the surface of a non-magnetic white dwarf (WD) for different viscosities which corresponds to different stages for…

Astrophysics · Physics 2015-06-24 Jacob Lund Fisker , Dinshaw S. Balsara

Close to a black hole, the density of the sub-Keplerian accreting matter becomes higher compared to a spherical flow due to the presence of a centrifugal barrier independent of whether or not a standing shock actually forms. This hot dense…

Astrophysics · Physics 2009-10-30 Sandip K. Chakrabarti

I review various phenomena associated with mass-accreting white dwarfs (WDs) in the view of supersoft X-ray sources. When the mass-accretion rate is low (\dot M_{acc} < a few \times 10^{-7} M_\sun yr^{-1}), hydrogen nuclear burning is…

Solar and Stellar Astrophysics · Physics 2015-05-14 Mariko Kato

The accretion flow in the disk dominated state of black hole binaries has peak temperature and luminosity which vary together in such a way as to indicate an approximately constant emitting area. The association of this with the last stable…

Astrophysics · Physics 2009-11-13 Chris Done , Shane W. Davis

The Eclipse Mapping Method is an indirect imaging technique that transforms the shape of the eclipse light curve into a map of the surface brightness distribution of the occulted regions. Three decades of application of this technique to…

Solar and Stellar Astrophysics · Physics 2015-08-14 Raymundo Baptista

Understanding how mass and angular momentum flow through accretion discs remains a fundamental unsolved problem in astrophysics. Accreting white dwarfs offer an ideal laboratory for addressing this question: their variability occurs on…

The X-ray spectra of accreting stellar-mass black hole systems exhibit spectral features due to reflection, especially broad iron K alpha emission lines. We investigate the reflection by the accretion disc that can be expected in the…

Astrophysics · Physics 2009-11-13 R. R. Ross , A. C. Fabian

The existing disk instability model for dwarf nova eruptions is reviewed, in the light of recent progress in the understanding of angular momentum transport in accretion disks. It is proposed that the standard lower branch in the…

Astrophysics · Physics 2007-05-23 Mario Livio

White dwarfs experience a thermal renaissance when they receive mass from a stellar companion in a binary. For accretion rates < 10^-8 Msun/yr, the freshly accumulated hydrogen/helium envelope ignites in a thermally unstable manner that…

Astrophysics · Physics 2009-11-07 Dean M. Townsley , Lars Bildsten

We present an analysis of the FUSE spectra of eight high-declination dwarf novae obtained from a Cycle 7 FUSE survey. These DN systems have not been previously studied in the UV and little is known about their white dwarfs (WDs) or…

Solar and Stellar Astrophysics · Physics 2009-08-05 P. Godon , E. M. Sion , P. E. Barrett , P. Szkody