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Related papers: The orbital period changes for novae

200 papers

Recent spectroscopic observations have identified several cataclysmic variables non-solar metal abundances. We present theoretical models which examine the level of core evolution expected for CV secondaries prior to contact. Our results…

Astrophysics · Physics 2015-06-24 Steve B. Howell

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…

(Shortened) Sequences of spectra of the nova-like cataclysmic variable (CV) BZ Cam were acquired on 9 nights in 2005-2006 in order to study the time development of episodes of wind activity known to occur frequently in this star. We confirm…

Solar and Stellar Astrophysics · Physics 2013-01-04 Kent Honeycutt , Stella Kafka , Jeff Robertson

Archival data on permanent superhump systems are compiled to test the thermal stability of their accretion discs. We find that their discs are almost certainly thermally stable as expected. This result confirms Osaki's suggestion (1996)…

Astrophysics · Physics 2009-10-31 A. Retter , T. Naylor

We focus on short--period eclipsing binaries that belong to a class of Cataclysmic Variables (CVs). They are known as polars and intermediate polars, closely resembling their prototype AM Herculis. These binaries consist of a red dwarf and…

Earth and Planetary Astrophysics · Physics 2014-03-20 Aga Słowikowska , Krzysztof Goździewski , Ilham Nasiroglu , Gottfried Kanbach , Arne Rau , Krzysztof Krzeszowski

We report the discovery of two new magnetic cataclysmic variables with brown dwarf companions and long orbital periods ($P_{\rm orb}=95\pm1$ and $104\pm2$ min). This discovery increases the sample of candidate magnetic period bouncers with…

Current evolutionary models imply that most Cataclysmic Variables (CVs) have P_orb<2 hours and are Dwarf Nova (DN) systems that are quiescent most of the time. Observations of nearby quiescent DN find that the UV spectrum is dominated by…

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

Many high-state cataclysmic variables (CVs) exhibit blue-shifted absorption features in their ultraviolet (UV) spectra -- a smoking-gun signature of outflows. However, the impact of these outflows on {\em optical} spectra remains much more…

Solar and Stellar Astrophysics · Physics 2024-06-21 Yusuke Tampo , Christian Knigge , Knox S. Long , James H. Matthews , Noel Castro Segura

We redetermine the relationship between absolute magnitude and orbital period for dwarf novae, based on 46 stars with good distance estimates. This improves upon Warner's previous relation, building upon today's improved estimates of…

Solar and Stellar Astrophysics · Physics 2010-10-26 Joseph Patterson

We review the most decisive currently available measurements of the surface effective temperatures, Teff, of white dwarf (WD) primaries in cataclysmic variables (CVs) during accretion quiescence, and use these as a diagnostic for their time…

Astrophysics · Physics 2011-02-11 Dean M. Townsley , Boris T. Gaensicke

We show that the secondaries in short-period cataclysmic variables with orbital periods $P < 3$ hr are close to the solar-abundance main sequence defined by single field stars. In cataclysmic variables with $P > 3$ hr, the earliest spectral…

Astrophysics · Physics 2007-05-23 K. Beuermann , I. Baraffe , U. Kolb , M. Weichhold

Astrophysical jets seem to occur in nearly all types of accreting objects: from supermassive black holes to young stellar objects. Based on X-ray binaries, a unified scenario describing the disc/jet coupling has evolved and extended to many…

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…

Solar and Stellar Astrophysics · Physics 2018-01-31 J. V. Hernandez Santisteban , C. Knigge , M. L. Pretorius , M. Sullivan , B. Warner

The 2dF QSO survey is a spectroscopic survey of 48,000 point-sources selected by colour with magnitudes in the range 18.35 < B < 20.95. Amongst QSOs, white dwarfs, narrow-line galaxies and other objects are some cataclysmic variables (CVs).…

We have obtained observations of the ultraviolet spectrum of AM CVn, an ultra-short-period helium cataclysmic variable, using the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope (HST). We obtained data in…

Astrophysics · Physics 2019-08-14 Richard A. Wade , Michael Eracleous , Helene M. L. G. Flohic

Novae have been reported as transients for more than two thousand years. Their bright optical outbursts are the result of explosive nuclear burning of gas accreted from a binary companion onto a white dwarf. Novae containing a white dwarf…

Solar and Stellar Astrophysics · Physics 2015-09-29 Julian P. Osborne

Fluctuations during a prolonged maximum have been observed in several nova eruptions, although it is not clear, and can not be deduced directly from observations, if the phenomenon is an actual physical reaction to some mechanism…

Solar and Stellar Astrophysics · Physics 2022-08-16 Yael Hillman

We present spectroscopic and photometric observations of the cataclysmic variable CW 1045+525. Both the optical spectrum and the photometric lightcurve show a strong contribution of a K5V - M0V secondary. We derive an orbital period P_orb =…

Astrophysics · Physics 2009-11-07 C. Tappert , J. R. Thorstensen , W. H. Fenton , N. Bennert , L. Schmidtobreick , A. Bianchini

The physical mechanism driving mass ejection during a nova eruption is still poorly understood. Possibilities include ejection in a single ballistic event, a common envelope interaction, a continuous wind, or some combination of these…