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The observed orbital period distribution of cataclysmic variables (CVs), the space density derived from observations, and the observed orbital period minimum are known to disagree with theoretical predictions since decades. More recently,…

太阳与恒星天体物理 · 物理学 2015-12-11 Matthias R. Schreiber , Monica Zorotovic , Thomas P. G. Wijnen

We present high-speed, multicolour photometry of the faint, eclipsing cataclysmic variable (CV) SDSS J105754.25+275947.5. The light from this system is dominated by the white dwarf. Nonetheless, averaging many eclipses reveals additional…

The orbital periods of most eclipsing cataclysmic binaries are not undergoing linear secular decreases of order a few parts per billion as expected from simple theory. Instead, they show several parts per million increases and decreases on…

太阳与恒星天体物理 · 物理学 2021-08-18 Michael M. Shara , Steve B. Howell , Elise Furlan , Crystal L. Gnilka , Anthony F. J. Moffat , Nicholas J. Scott , David Zurek

We present the first population synthesis of synchronous magnetic cataclysmic variables, called polars, taking into account the effect of the white dwarf (WD) magnetic field on angular momentum loss. We implemented the reduced magnetic…

太阳与恒星天体物理 · 物理学 2019-12-25 Diogo Belloni , Matthias R. Schreiber , Anna F. Pala , Boris T. Gänsicke , Mónica Zorotovic , Claudia V. Rodrigues

AM Her variables -- synchronised magnetic cataclysmic variables (CVs) -- exhibit a different period distribution from other CVs across the period gap. We show that non-AM Her systems may infiltrate the longer-period end of the period gap if…

天体物理学 · 物理学 2009-11-07 R. F. Webbink , D. T. Wickramasinghe

We present spectroscopy and orbital periods Porb for 30 apparently non-magnetic cataclysmic binaries with periods below about 3 hours, nearly all of which are dwarf novae, mostly of the SU Ursae Majoris subclass. We then turn to the…

太阳与恒星天体物理 · 物理学 2020-06-17 John R. Thorstensen

Many of the current problems related to the evolution of cataclysmic variables revolve around the magnetic nature of the main sequence secondary. It is known that magnetic fields alter the structure of low mass stars. In particular, they…

太阳与恒星天体物理 · 物理学 2025-07-10 Conor M. Larsen , James MacDonald

The predicted and observed space density of cataclysmic variables (CVs) have been for a long time discrepant by at least an order of magnitude. The standard model of CV evolution predicts that the vast majority of CVs should be period…

During a visual search through the Kepler main-field lightcurves, we have discovered a cataclysmic variable (CV) that experienced only a single 4-day long outburst over four years, rising to three times the quiescent flux. During the four…

We report the results of a statistical study of cyclical period changes in cataclysmic variables (CVs). Assuming the third-body hypothesis as the cause of period changes, we estimate the third-body mass, $m_3$, and its separation from the…

太阳与恒星天体物理 · 物理学 2024-08-16 Leandro Souza , Raymundo Baptista

We present the first volume-limited sample of cataclysmic variables (CVs), selected using the accurate parallaxes provided by the second data release (DR2) of the ESA $\mathit{Gaia}$ space mission. The sample is composed of 42 CVs within…

We discuss the properties of 137 cataclysmic variables (CVs) which are included in the Sloan Digital Sky Survey (SDSS) spectroscopic data base, and for which accurate orbital periods have been measured. 92 of these systems are new…

We present high-speed, three-colour photometry of the eclipsing dwarf nova PHL 1445, which, with an orbital period of 76.3 min, lies just below the period minimum of ~82 min for cataclysmic variable stars. Averaging four eclipses reveals…

We resume the discussion about irradiation-driven mass transfer cycles in semi- detached compact binary systems. The analytical model that describes the onset of these cycles, which occur on a thermal timescale of the donor star, is…

天体物理学 · 物理学 2009-11-10 A. Büning , H. Ritter

The overwhelming majority of CVs have orbital periods shorter than 10 hr. However, a few have much longer periods, and their formation and existence pose challenges for the CV evolution models. These extremely long-period CVs must host…

Although a large number of orbital periods of cataclysmic variable stars (CVs) have been measured, comparison of period and luminosity distributions with evolutionary theory is affected by strong selection effects. A test has been…

天体物理学 · 物理学 2009-11-07 R. C. North , T. R. Marsh , U. Kolb , V. S. Dhillon , C. K. J. Moran

CSS1603+19 is a cataclysmic variable (CV) with an orbital period of 81.96 min, near the minimal period of cataclysmic variables. It is unusual in having a strong mid-infrared excess inconsistent with thermal emission from a brown dwarf…

太阳与恒星天体物理 · 物理学 2023-04-26 Yiqi Liu , Hsiang-Chih Hwang , Nadia L. Zakamska , John R. Thorstensen

Context. For decades, reproducing the orbital period distribution of non-magnetic Cataclysmic Variables (CVs) seemed to require a drastic decrease, usually termed disruption, of angular momentum loss through magnetic braking at the fully…

太阳与恒星天体物理 · 物理学 2026-04-15 Joaquín A. Barraza-Jorquera , Matthias R. Schreiber , Stuart Littlefair , Diogo Belloni , Axel D. Schwope

Binary evolution theory predicts that accreting white dwarfs with sub-stellar companions dominate the Galactic population of cataclysmic variables (CVs). In order to test these predictions, it is necessary to identify these systems, which…

太阳与恒星天体物理 · 物理学 2018-01-31 J. V. Hernandez Santisteban , C. Knigge , M. L. Pretorius , M. Sullivan , B. Warner

Magnetic cataclysmic variables (CVs) contain a white dwarf with magnetic field strong enough to control the accretion flow from a late type secondary. In this paper, we discover a magnetic CV (CXOGSG J215544.4+380116) from the $Chandra$…

太阳与恒星天体物理 · 物理学 2017-02-01 Song Wang , Yu Bai , Chuan-peng Zhang , Ji-feng Liu