We present 8–12 GHz radio light curves of five dwarf nova (DN) type Cataclysmic Variable stars (CVs) in outburst (RX And, U Gem and Z Cam), or superoutburst (SU UMa and YZ Cnc), increasing the number of radio-detected DN by a factor of two. The observed radio emission was variable on time-scales of minutes to days, and we argue that it is likely to be synchrotron emission. This sample shows no ...

We report the first observed outburst of the magnetic cataclysmic variable XY Ari. Xray observations show a flux increase by an order of magnitude the day after the first signs of outburst. During the 5-d duration the X-ray spin pulse is greatly enhanced and the X-ray spectrum far more absorbed. We suggest that the inner disc pushes inwards during outburst, blocking the view to the lower accret...

We report simultaneous photometric and echelle-spectroscopic observations of the dwarf nova BZ UMa during which we were lucky to catch the system at the onset of an outburst, the development of which we traced in detail from quiescence to early decline. The outburst had a precursor, and was of a short duration (∼5 days) with a highly asymmetrical light curve. On the rise we observed a 'jump' du...

We report on a campaign of X-ray and soft γ-ray observations of the black hole candidate H 1743-322 (also named IGR J17464-3213), performed with the RXTE, INTEGRAL and Swift satellites. The source was observed during a short outburst between 2008 October 03 and 2008 November 16. The evolution of the hardness-intensity diagram throughout the outburst is peculiar, in that it does not follow the c...

The challenges of significant network dynamics and limited bandwidth capacities have to be considered when designing efficient algorithms for distributing large volumes of content in overlay networks. This paper presents Outburst, a novel approach for overlay content distribution based on rateless codes. In Outburst, we code content bitstreams with rateless codes at the source, and take advanta...

We find a strong correlation between the optical outburst amplitude ∆V and orbital period Porb for the soft X-ray transient sources with orbital periods less than 1 day. By fitting the observed values for 8 X-ray transients we determine an empirical relation that can be used to predict the orbital period of an X-ray transient given only its outburst amplitude: ∆V = 14.36− 7.63 logPorb(h). For p...

We observed the long-term behavior of the helium dwarf nova V803 Cen, and clarified the existence of at least two distinct states (a state with 77-d supercycles and a standstill-like state) that interchangeably appeared with a time-scale of 1–2 yr. We also conducted a time-resolved CCD photometry campaign during the bright outburst in 2003 June. The overall appearance of the outburst closely re...

We observed long-term behavior of the helium dwarf nova V803 Cen, and clarified the existence of at least two distinct states (state with 77-d supercycles and standstill-like state) which interchangeably appeared with a time-scale of 1–2 yr. We also conducted a time-resolved CCD photometry campaign during the bright outburst in 2003 June. The overall appearance of the outburst closely resemble ...

XTE J1739–302 is a transient X-ray source with unusually short outbursts, lasting on the order of hours. Here we give a summary of X-ray observations we have made of this object in outburst with the Rossi X-ray Timing Explorer (RXTE) and at a low level of activity with the Chandra X-ray Observatory, as well as observations made by other groups. Visible and infrared spectroscopy of the mass dono...