Search results for "Cataclysmic variable star"

showing 3 items of 3 documents

A 60-night campaign on dwarf novae. - I. Photometric variability of SU UMa and YZ Cnc

1994

A 60-night campaign on SU UMa, YZ Cnc and some secondary targets was carried out during 1988 December and 1989 January at the Observatorio del Roque de Los Muchachos (the 1988 International Time Project). The aim was to study the behaviour of these dwarf novae through their outburst cycle. Here we present the overall light curves of the main targets, SU UMa and YZ Cnc, which show that the optical fluxes continue to decrease after the end of the outburst. For YZ Cnc we find that, during quiescence, orbital variability is present, which may be interpreted as modulation caused by the bright-spot region. Near the end of an outburst, a weak, sinusoidal variation is observed; we discuss the possi…

PhysicsAccretion discSpace and Planetary ScienceBinary starAstronomyCataclysmic variable starAstronomy and AstrophysicsAstrophysicsVariation (astronomy)Light curveMonthly Notices of the Royal Astronomical Society
researchProduct

A three-dimensional smoothed particle hydrodynamics simulation of the active phase of SS Cyg-type discs and its implications for the mass transfer bu…

1993

We perform a smoothed particle hydrodynamics (SPH) three-dimensional simulation of the outburst phase of the accretion disc of a typical SS Cyg-like dwarf nova in the framework of the mass transfer burst model (MTBM), where we assume that the active phase is triggered by a sudden increase in the accretion rate due to some instability in the secondary's atmosphere. The evolution of the accretion disc is followed for a single orbital period, starting from the initial quiescent disc configuration obtained by us in a previous paper. This is a suitable integration time for determining the geometrical and physical properties of the disc in the impulsive phase and is comparable with observed outbu…

PhysicsComputer simulationAstrophysics::High Energy Astrophysical PhenomenaCataclysmic variable starAstronomy and AstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsOrbital periodInstabilityAccretion (astrophysics)Smoothed-particle hydrodynamicsSpace and Planetary ScienceMass transferAstrophysics::Solar and Stellar AstrophysicsAstrophysics::Earth and Planetary AstrophysicsDwarf novaAstrophysics::Galaxy AstrophysicsMonthly Notices of the Royal Astronomical Society
researchProduct

X-RAY SPECTROSCOPIC DIAGNOSIS OF A WIND-COLLIMATED BLAST WAVE AND METAL-RICH EJECTA FROM THE 2006 EXPLOSION OF RS OPHIUCHI

2009

Chandra HETG observations of RS Ophiuchi at day 13.9 of the 2006 outburst reveal a rich spectrum of emission lines from abundant ions formed over a wide temperature range (∼ 3 × 10 6 to 60 × 10 6 K) indicative of shock heating of the circumstellar medium by the expanding blast wave. Lines are asymmetric and strongly broadened (v ∼ 2400 km s −1 at zero intensity). Using simple analytical model profiles, we show how the lines are shaped by differential absorption in the red giant wind and explosion ejecta, and that shock heating to multimillion degree temperatures appears to have occurred preferentially in the direction perpendicular to the line of sight. We conclude that the asymmetric natur…

PhysicsShock waveRed giantAstrophysics::High Energy Astrophysical PhenomenaX-ray binaryAstronomyCataclysmic variable starAstronomy and AstrophysicsAstrophysicsSpace and Planetary ScienceRS OphiuchiAstrophysics::Solar and Stellar AstrophysicsEmission spectrumEjectaAstrophysics::Galaxy AstrophysicsBlast waveThe Astrophysical Journal
researchProduct