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In order to determine the spatial distribution, Galactic model parameters and luminosity function of cataclysmic variables (CVs), a $J$-band magnitude limited sample of 263 CVs has been established using a newly constructed…

Astrophysics of Galaxies · Physics 2015-06-22 A. Ozdonmez , T. Ak , S. Bilir

The recent release of the second Gravitational-Wave Transient Catalog (GWTC-2) has increased significantly the number of known GW events, enabling unprecedented constraints on formation models of compact binaries. One pressing question is…

High Energy Astrophysical Phenomena · Physics 2021-04-28 Kaze W. K. Wong , Katelyn Breivik , Kyle Kremer , Thomas Callister

The cosmic microwave background (CMB) temperature anisotropies exhibit a large-scale dipolar power asymmetry. To determine whether this is due to a real, physical modulation or is simply a large statistical fluctuation requires the…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 D. Contreras , J. P. Zibin , D. Scott , A. J. Banday , K. M. Górski

We report on our survey for rapid (time scale of minutes) photometric variability in symbiotic binaries. These binaries are becoming an increasingly important place to study accretion onto white dwarfs since they are candidate Type Ia…

Astrophysics · Physics 2009-11-06 J. L. Sokoloski , Lars Bildsten , Wynn C. G. Ho

Approximately $0.2 \pm 0.2$ of white dwarfs (WDs) show signs of pollution by metals, which is likely due to the accretion of tidally disrupted planetary material. Models invoking planet-planet interactions after WD formation generally…

Earth and Planetary Astrophysics · Physics 2016-08-03 Adrian S. Hamers , Simon F. Portegies Zwart

Previous X-ray observations toward the Nuclear Star Cluster (NSC) at the Galactic center have discovered thousands of point sources, most of which were believed to be cataclysmic variables (CVs), i.e., a white dwarf (WD) accreting from a…

High Energy Astrophysical Phenomena · Physics 2019-09-23 Xiao-jie Xu , Zhiyuan Li , Zhenlin Zhu , Zhongqun Cheng , Xiang-dong Li , Zhuo-li Yu

More than 20 pre-cataclysmic variable (pre-CV) systems have now been discovered with very short orbital periods ranging from 250 min down to 68 min. A pre-CV consists of a white dwarf or hot subdwarf primary and a low-mass companion star,…

Solar and Stellar Astrophysics · Physics 2018-10-24 L. Nelson , J. Schwab , M. Ristic , S. Rappaport

Using a parameterised function for the mass loss at the base of the post-shock region, we have constructed a formulation for magnetically confined accretion flows which avoids singularities, such as the infinity in density, at the base…

Astrophysics · Physics 2009-11-06 Kinwah Wu , Mark Cropper

Magnetic braking (MB) plays an important role in the evolution of close low-mass X-ray binaries (LMXBs). It is also essential to the formation of ultracompact X-ray binaries (UCXBs). There have been lively investigations on the MB…

High Energy Astrophysical Phenomena · Physics 2024-07-16 Zhuling Deng , Xiangdong Li

Ultracompact binary systems, consisting of two compact objects in an orbit $\lesssim 0.5 R_\odot$, should exhibit measurable rates of orbital period change ($\dot{P} \neq 0$) due to the emission of gravitational waves (GWs). Measurements of…

Cataclysmic variables undergo periodic nova explosions during which a finite mass of material is expelled on a short timescale. The system widens and, as a result, the mass-transfer rate drops. This state of hibernation may account for the…

Astrophysics · Physics 2008-11-26 Rebecca G. Martin , Christopher A. Tout

This is the second paper of a series presenting our search for magnetic Cataclysmic Variables (mCVs) among candidates selected mostly from the Catalina Real-Time Transient Survey (CRTS). We present the identification spectra, obtained at…

While highly evolved cataclysmic variables (CVs) with brown dwarf donors, often called "period bouncers", are predicted to make up $\simeq40-70$ % of the Galactic CV population, only a handful of such systems are currently known. The…

Solar and Stellar Astrophysics · Physics 2018-10-01 Anna F. Pala , Linda Schmidtobreick , Claus Tappert , Boris T. Gänsicke , Andrea Mehner

We studied two objects identified as a Cataclysmic Variables (CVs) with periods exceeding the natural boundary for Roche lobe filling ZAMS secondary stars. We present observational results for V1082 Sgr with 20.82 h orbital period, an…

The magnetic fields of the accreting white dwarfs (WDs) in magnetic cataclysmic variables (mCVs) determine the accretion geometries, the emission properties, and the secular evolution of these objects. We determine the structure of the…

Astrophysics · Physics 2015-06-24 K. Beuermann , F. Euchner , K. Reinsch , S. Jordan , B. T. Gaensicke

By Polnarev's method we analytically calculate the polarization spectra of the cosmic microwave background radiation (CMB) generated by cosmic relic gravitational waves (RGW). In this analytic approach the physics involved in this…

Astrophysics · Physics 2008-11-26 Wen Zhao , Yang Zhang

Magnetic cataclysmic variables provide a natural laboratory for studying how accretion interacts with compact-object magnetospheres and generates stochastic variability. We present an optical variability study of the intermediate-polar…

The origin of magnetic fields in white dwarfs remains a fundamental unresolved problem in stellar astrophysics. In particular, the very different fractions of strongly (exceeding 1 MG) magnetic white dwarfs in evolutionarily linked…

Solar and Stellar Astrophysics · Physics 2021-05-03 Matthias R. Schreiber , Diogo Belloni , Boris T. Gaensicke , Steven G. Parsons , Monica Zorotovic

Cataclysmic variables (CVs) are binary systems consisting of a white dwarf (WD) accreting matter from a companion star. Observations of CVs provide an opportunity to learn about accretion disks, the physics of compact objects, classical…

In this paper, the first of a series, we study the stellar dynamical and evolutionary processes leading to the formation of compact binaries containing white dwarfs in dense globular clusters. We examine the processes leading to the…

Astrophysics · Physics 2009-11-11 N. Ivanova , C. O. Heinke , F. A. Rasio , R. E. Taam , K. Belczynski , J. Fregeau