Related papers: CH Cygni II: Optical Flickering from an Unstable D…

The connection between accretion and jet production in accreting white dwarf binary systems, especially dwarf novae, is not well understood. Radio wavelengths provide key insights into the mechanisms responsible for accelerating electrons,…

We performed 48.6 hours (in 28 nights) of simultaneous B and V band observations of the flickering variability of the recurrent nova RS Oph in quiescence. During the time of our observations the brightness of the system varied between 13.2…

We propose that relative variability on short time-scales of the multiple images of a lensed quasar, after removal of the time delay, may be caused by hot spots or other moving structures in the accretion disk crossing microlens caustics…

High spatial and spectral resolution observations of star formation and kinematics in early galaxies have shown that two-thirds are massive rotating disk galaxies with the remainder being less massive non-rotating objects. The line of sight…

Outflows in the form of fast winds from the accretion disk appear in nearly all high accretion rate cataclysmic variables (CVs), both novalikes (NLs) and dwarf novae in outburst (DN). The primary signatures of CV winds are broad,…

We explore the origin of FUSE and HST STIS far UV spectra of the dwarf nova, EY Cyg, during its quiescence using \emph{combined} high gravity photosphere and accretion disk models as well as model accretion belts. The best-fitting single…

We examine the consequences of radiatively driven warping of accretion disks surrounding pre-main-sequence stars. These disks are stable against warping if the luminosity arises from a steady accretion flow, but are unstable at late times…

While accreting through a circumstellar disk, young stellar objects are observed to undergo sudden and powerful accretion events known as FUor or EXor outbursts. Although such episodic accretion is considered to be an integral part of the…

Context. The disc instability model (DIM) successfully explains why many accreting compact binary systems exhibit outbursts, during which their luminosity increases by orders of magnitude. The DIM correctly predicts which systems should be…

We report results of the eclipse mapping analysis of an ensemble of light curves of HT Cas. The fast response of the white dwarf to the increase in mass transfer rate, the expansion rate of the accretion disc at the same time, and the…

The All Sky Monitor on the Rossi X-ray Timing Explorer detected an X-ray (2-12 keV) outburst from the black hole binary GRO J1655-40 beginning near April 25, 1996. Optical photometry obtained April 20-24, 1996 shows a steady brightening of…

Changing-look active galactic nuclei (CLAGN) feature order-of-magnitude variability in both the continuum and broad line luminosities on months-to-years long timescales, and are currently unexplained. Simulations have demonstrated that…

Cataclysmic Variables (CVs) are close binary systems where mass is transferred from a red dwarf star to a white dwarf star via an accretion disk. The flickering is observed as stochastic variations in the emitted radiation both in the…

We present the results of $WBVR$ observations of the low-mass X-ray binary V1341 $\textrm{Cyg} = \textrm{Cyg}$ X--2. Our observations include a total of 2375 individual measurements in four bands on 478 nights in 1986-1992. We tied the…

We present a new perspective on the crystallinity of dust in protoplanetary disks. The dominant crystallization by thermal annealing happens in the very early phases of disk formation and evolution. Both the disk properties and the level of…

In the framework of the dwarf nova thermal-viscous disc instability model, we investigate the combined effects on the predicted dwarf nova lightcurves of irradiating the accretion disc and the secondary star and of evaporating the inner…

RS Ophiuchi is a recurrent nova system that experiences outbursts every ~20 years, implying accretion at a high rate onto a massive white dwarf. However, previous X-ray observations of the system in quiescence have detected only faint…

We present the first significant detection of relativistic smearing of the X-ray reflection spectrum from the putative accretion disk in the low/hard state of Cyg X--1. The ionization state, and amount of relativistic smearing are…

We explore the non-linear, high-frequency, aperiodic variability properties in the three cataclysmic variables MV Lyr, KIC 8751494 and V1504 Cyg observed with Kepler, as well as the X-ray binary Cyg X-1 observed with RXTE. This is done…

Observations of accreting systems often show significant variability (10-20 percent of accretion luminosity) on timescales much longer than expected for the disc regions releasing most of the luminosity. We propose an explicit physical…