We report null results on a two year photometric search for outburst predictors in SS Cyg. Observations in Johnson V and Cousins I were obtained almost daily for multiple hours per night for two observing seasons. The accumulated data are put through various statistical and visual analysis techniques but fails to detect any outburst predictors. However, analysis of 102 years of AAVSO archival v...

A continuum growth model is introduced. The state at time t, St, is a subset of R and consists of a connected union of randomly sized Euclidean balls, which emerge from outbursts at their center points. An outburst occurs somewhere in St after an exponentially distributed time with expected value |St| −1 and the location of the outburst is uniformly distributed over St. The main result is that ...

From archived and recent high speed photometry of VW Hyi we find Dwarf Nova Oscillations (DNOs) occasionally present throughout outburst, evolving from 14.06 s period at maximum to > 40 s near the end of outburst. A relatively slow increase of period is followed by rapid increase and subsequent decrease. Quasi-periodic Oscillations (QPOs) are seen at periods of hundreds of seconds. For the firs...

Determining the influence scope of airflow disorder is an important problem after coal and gas outburst accidents in ventilation systems. This paper puts forward indexes disorder, including length excavation roadway, pressure, pressure difference air door, quantity auxiliary fan. Using orthogonal table L9 (34) numerical simulation method, characteristics reversal are studied, degree calculated ...

In view of the high gas pressure and low permeability deep coal seam, it is difficult to control gas, which affects safety production mine. The technical scheme hydraulic fracturing improve seam put forward, drainage technology used emission seam. effect under different water pressure, gradient times, in situ stress analyzed by using 3DEC (3-Dimensional Distinct Element Code) discrete element s...

We report photometry and spectroscopy of the evolution of Nova Sagittarii 1994 #1 (V4332 Sagittarii) during outburst. We compare the photometric and spectral evolution of this outburst to known classes of outbursts – including classical novae and outbursts occurring on symbiotic stars – and find this object does not conform to any known class of outburst. The closest match to the behavior of th...

We study the prospect of explaining the outbursts of Soft X-ray Transients (SXTs) by the thermalviscous instability in a thin disc. This instability is linked to hydrogen ionization and is significantly changed when irradiation of the disc by X-rays from the inner regions is included. We present the first numerically reliable, physically consistent calculations of the outburst cycles which incl...

In June–September 2006 the Be/X-ray binary EXO 2030+375 experienced the second giant outburst since its discovery. The source was shown to have a complicated pulse-averaged X-ray spectral continuum with possible evidence of cyclotron absorption features. In this paper we present the first pulse-phase resolved analysis of the broad band X-ray spectra of EXO 2030+375 obtained with the INTEGRAL ob...