Related papers: On the accretion disc properties in eclipsing dwar…
We describe a model for the long term evolution of a circumplanetary disk that is fed mass from a circumstellar disk and contains regions of low turbulence (dead zones). We show that such disks can be subject to accretion driven outbursts,…
We show for five DN systems, SS Cyg, VW Hyi, RU Peg, WW Cet and T Leo that the UV and X-ray power spectra of their time variable light curves are similar in quiescence. All of them show a break in their power spectra, which in the framework…
(Abridged) We use optical spectroscopy to investigate the disk, wind, and accretion during the 2008 ZCMa NW outburst. Over 1000 optical emission lines reveal accretion, a variable, multi-component wind, and double-peaked lines of disk…
We present the last HST/STIS E140M FUV spectrum (1150-1725A) of the dwarf nova (DN) WZ Sge, obtained in July 2004, 3 years following the early superoutburst of July 2001. Single white dwarf (WD) synthetic spectral fits (log{g}=8.5) to the…
We present the analysis of optical photometric and spectroscopic observations of two non-magnetic cataclysmic variables, namely CRTS J080846.2+313106 and V416 Dra. CRTS J080846.2+313106 has been found to vary with a period of…
Our previous theoretical study of the impact of an accreting envelope on the thermal state of an underlying white dwarf (WD) has yielded equilibrium core temperatures, classical nova ignition masses and thermal luminosities for WDs…
FO Aquarii, an asynchronous magnetic cataclysmic variable (intermediate polar) went into a low-state in 2016, from which it slowly and steadily recovered without showing dwarf nova outbursts. This requires explanation since in a low-state,…
We present time-dependent nova outburst models with optically thick winds for a 1.2 and 1.35 $M_\odot$ white dwarfs (WDs) with a mass accretion rate of $5 \times 10^{-9}~M_\odot$ yr$^{-1}$ and for a 1.3 $M_\odot$ WD with $2 \times…
We present ROSAT X-ray and optical light curves of the 1994 February superoutburst of the eclipsing SU UMa dwarf nova OY Carinae. There is no eclipse of the flux in the ROSAT HRI light curve. Contemporaneous `wide B' band optical light…
Some accreting neutron stars and young stars show unexplained episodic flares in the form of quasi-periodic oscillations or recurrent outbursts. In a series of two papers we present new work on an instability that can lead to episodic…
We use a combined binary evolution code including dynamical effects to study nova eruptions in a symbiotic system. Following the evolution, over $\sim10^5$ years, of multiple consecutive nova eruptions on the surface of a $1.25M_\odot$…
We analyse here four observations of nova KT Eri (Nova Eri 2009) done with the Chandra High Resolution Camera Spectrometer (HRC-S) and the Low Energy Transmission Grating (LETG) in 2010, from day 71 until day 159 after the optical maximum,…
In this note we study the accretion disc that arises in hypercritical accretion of $\dot M\sim 10^8 M_{\rm Edd}$ onto a neutron star while it is in common envelope evolution with a massive companion. In order to raise the temperature high…
The old nova V728 Sco has been recently recovered via photometric and spectroscopic observations, 150 years after the nova eruption. The spectral properties pointed to a high-inclination system with a comparatively low mass-transfer rate.…
We show that if the dwarf-nova disc instability model includes the effects of heating by stream impact and tidal torque dissipation in the outer disc, the calculated properties of dwarf-nova outbursts change considerably, and several…
We apply an eclipse mapping technique using `genetically modified fire-flies' to the eclipse light curves of HU Aqr and EP Dra. The technique makes as few assumptions as possible about the location of accretion stream material, allowing the…
We reanalyse archival GINGA and ASCA X-ray data from SS Cyg in both quiescence and outburst, using multi-temperature plasma models for the continuum and line emission, together with their reflection from the X-ray illuminated white dwarf…
The iPTF detection of the most recent outburst of the recurrent nova system RX J0045.4+4154 in the Andromeda Galaxy has enabled the unprecedented study of a massive ($M>1.3\ M_\odot$) accreting white dwarf (WD). We detected this nova as…
We present an analysis of X-ray and ultra-violet data of the dwarf nova VW Hyi that were obtained with XMM-Newton during the quiescent state. The X-ray spectrum indicates the presence of an optically thin plasma in the boundary layer that…
We have measured the orbital light curve of dwarf nova OY Carinae on 8 separate occasions between 1997 September and 2005 December. The measurements were made in white light using CCD photometers on the Mt Canopus 1 m telescope. The time of…