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Related papers: The cataclysmic variable QZ Lib: a period bouncer

200 papers

Context. We present time-resolved spectroscopy and photometry of HS 0218+3229, a new long-period cataclysmic variable discovered within the Hamburg Quasar Survey. It is one of the few systems that allow a dynamical measurement of the masses…

Solar and Stellar Astrophysics · Physics 2009-11-13 P. Rodríguez-Gil , M. A. P. Torres , B. T. Gänsicke , T. Muñoz-Darias , D. Steeghs , R. Schwarz , A. Rau , H. -J. Hagen

Continuing our work from Paper I (Southworth et al., 2006) we present medium-resolution spectroscopy and broad-band photometry of seven cataclysmic variables (CVs) discovered by the SDSS. For six of these objects we derive accurate orbital…

The mass-loss rate of donor stars in cataclysmic variables (CVs) is of paramount importance in the evolution of short-period CVs. Observed donors are oversized in comparison with those of isolated single stars of the same mass, which is…

Solar and Stellar Astrophysics · Physics 2015-05-19 Fedir V. Sirotkin , Woong-Tae Kim

Outbursts in two classes of interacting binary systems, the symbiotic stars (SSs) and the cataclysmic variables (CVs), show a number of similarities in spite of very different orbital periods. Typical values for SSs are in the order of…

Solar and Stellar Astrophysics · Physics 2015-02-18 Augustin Skopal

EX Dra is a long-period eclipsing dwarf nova with $\sim2-3$ mag amplitude outbursts. This star has been monitored photometrically from November, 2009 to March, 2016 and 29 new mid-eclipse times were obtained. By using new data together with…

Astrophysics of Galaxies · Physics 2017-06-28 Zhong-tao Han , Sheng-bang Qian , Irina Voloshina , Li-Ying Zhu

The white dwarf in AM Her systems is strongly magnetic and keeps in synchronous rotation with the orbit by magnetic coupling to the secondary star. As the latter evolves through mass loss to a cool, degenerate brown dwarf it can no longer…

Astrophysics · Physics 2009-10-31 F. Meyer , E. Meyer-Hofmeister

We present high time-resolution spectroscopy of the eclipsing cataclysmic variable SDSSJ143317.78+101123.3 obtained with QUCAM2, a high-speed/low-noise electron-multiplying CCD camera. Littlefair et al. measured the mass of the secondary…

Solar and Stellar Astrophysics · Physics 2015-05-13 S. M. Tulloch , P. Rodriguez-Gil , V. S. Dhillon

We report the occurrence of a deep low state in the eclipsing short-period cataclysmic variable IR Com, lasting more than two years. Spectroscopy obtained in this state shows the system as a detached white dwarf plus low-mass companion,…

Solar and Stellar Astrophysics · Physics 2015-06-18 C. J. Manser , B. T. Gaensicke

We present time-series VLT spectroscopy and NTT photometry of the cataclysmic variable SDSS J220553.98+115553.7, which contains a pulsating white dwarf. We determine a spectroscopic orbital period of 82.825 +/- 0.089 min from velocity…

Astrophysics · Physics 2009-11-13 John Southworth , D W Townsley , B T Gaensicke

We present a study of the cataclysmic variable star PT Per based on archival XMM-Newton X-ray data and new optical spectroscopy from the WHT with ISIS. The X-ray data show deep minima which recur at a period of 82 minutes and a hard,…

High Energy Astrophysical Phenomena · Physics 2016-06-08 Mike Watson , Alastair Bruce , Chelsea MacLeod , Julian Osborne

Cataclysmic variables (CVs) are binaries in which a compact white dwarf accretes material from a low-mass companion star. The discovery of two planets in orbit around the CV HU Aquarii opens unusual opportunities for understanding the…

Earth and Planetary Astrophysics · Physics 2015-06-11 Simon Portegies Zwart

We report the identification of cyclical changes in the orbital period of the eclipsing cataclysmic variable HT Cas. We measured new white dwarf mid-eclipse timings and combined with published measurements to construct an…

Astrophysics · Physics 2009-11-13 B. W. Borges , R. Baptista , C. Papadimitriou , O. Giannakis

We report the discovery of one unique cataclysmic variable drawn from the Hamburg Quasar Survey, HS2331+3905. Follow-up observations obtained over three years unveiled a very unusual picture. The large amplitude 3.5 h radial velocity…

We present VLT and Magellan spectroscopy and NTT photometry of nine faint cataclysmic variables (CVs) which were spectroscopically identified by the SDSS. We measure orbital periods for five of these from the velocity variations of the…

WZ Sge-type dwarf novae are characterized by long recurrence times of outbursts (~10 yr) and short orbital periods (<~ 85 min). A significant part of WZ Sge stars may remain undiscovered because of low outburst activity. Recently, the…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. Uemura , T. Kato , D Nogami , T. Ohsugi

AM CVn systems are a rare type of accreting binary that consists of a white dwarf and a helium-rich, degenerate donor star. Using the Zwicky Transient Facility (ZTF), we searched for new AM CVn systems by focusing on blue, outbursting…

We report the discovery of a relatively bright eclipsing binary system, which consists of a white dwarf and a main sequence K7 star with clear signs of chromospheric and spot activity. The light curve of this system shows $\sim0.2$mag…

The Dwarf Nova Oscillations observed in Cataclysmic Variable (CV) stars are interpreted in the context of a Low Inertia Accretor model, in which accretion on to an equatorial belt of the white dwarf primary causes the belt to vary its…

Astrophysics · Physics 2009-11-07 Brian Warner , Patrick A. Woudt

We present high-speed photometry of the eclipsing cataclysmic variable CSS131106 J052412+004148. We determine the system parameters by modelling the eclipse lightcurve using the photometric eclipse method, in which the mass ratio is…

We report the first radial velocity spectroscopic study of the eclipsing period bouncer SDSS J105754.25+275947.5. Together with eclipse light curve modeling, we redetermined the system parameters and studied the accretion disk structure. We…

Solar and Stellar Astrophysics · Physics 2023-11-21 J. Echevarria , S. Zharikov , I. Mora Zamora