Related papers: Superhumps and their Amplitudes
We present observations and analysis of the first reported superoutburst of the dwarf nova SDSSp J082409.73+493124.4 during February/March 2007. From a maximum observed magnitude of 15.4C it declined at 0.09 mag/d for 7 days, flattened out…
Negative superhumps are believed to arise in cataclysmic variable systems when the accretion disk is tilted with respect to the orbital plane. Slow retrograde precession of the line-of-nodes results in a signal---the negative…
The black-hole X-ray transient MAXI J1820+07 (=ASSASN-18ey) discovered in March 2018 was one of the optically brightest ever seen, which has resulted in very detailed optical outburst light-curves being obtained. We combine them here with…
We numerically study the precessing disk model for superhump in the SU~UMa subclass of cataclysmic variables, using a two dimensional SPH code specifically designed for thin disk problems. Two disk simulations for a binary with mass ratio…
We propose a new dynamical method to estimate binary mass ratios by using the period of superhumps in SU UMa-type dwarf novae during the growing stage (the stage A superhumps). This method is based on a working hypothesis in which the…
We investigate the primordial curvature perturbation by the observation of dark matter substructure. Assuming a bump in the spectrum of the curvature perturbation in the wavenumber of k>1 Mpc^{-1}, we track the evolution of the host halo…
We report a CCD optical photometry of a dwarf nova AL Com in superoutburst. Before superhumps occurred the light curve was highly variable with dominant periods about 41 minutes and 81.5 minutes for different nights. The period of observed…
We present observations of the dwarf novae GW Lib, V844 Her, and DI UMa. Radial velocities of H-alph yield orbital periods of 0.05332 +- 0.00002 d (= 76.78 m) for GW Lib and and 0.054643 +- 0.000007 d (= 78.69 m) for V844 Her. Recently, the…
We report extensive photometry of the dwarf nova V419 Lyr throughout its 2006 July superoutburst till quiescence. The superoutburst with amplitude of ~3.5 magnitude lasted at least 15 days and was characterized by the presence of clear…
We observed the 2001 November superoutburst of CC Cnc. This observation makes the first detailed coverage of a superoutburst of this object. The best-determined mean superhump period is 0.075518 +/- 0.000018 d, which is 2.7% longer than the…
We investigated the superhump evolution, analysing optical photometric observations of the 2000 February-March, the 2002 October-November, and the 2006 September superoutbursts of SW UMa. The superhumps evolved in the same way after their…
I study the behaviour of the maximum rms fractional amplitude, $r_{\rm max}$ and the maximum coherence, $Q_{\rm max}$, of the kilohertz quasi-periodic oscillations (kHz QPOs) in a dozen low-mass X-ray binaries. I find that: (i) The maximum…
Protostellar systems, ranging from low-luminosity T Tauri and Herbig Ae stars to high-luminosity Herbig Be stars, exhibit a near-infrared (NIR) excess in their spectra that is dominated by a bump in the monochromatic luminosity with a peak…
I study the behaviour of the maximum rms fractional amplitude, $r_{\rm max}$ and the maximum coherence, $Q_{\rm max}$, of the kilohertz quasi-periodic oscillations (kHz QPOs) in a dozen low-mass X-ray binaries. I find that: (i) The maximum…
We report optical time-resolved photometric observations of a newly-discovered outbursting system, ASASSN-25dc. Its 8-mag amplitude, 40-day duration, 1-mag dip in the outburst plateau, and positive superhumps are characteristic of a dwarf…
We investigate the growth of tidal instabilities in accretion discs in a binary star potential, using three dimensional numerical simulations. As expected from analytic work, the disc is prone to an eccentric instability provided that it is…
The timing capabilities and sensitivity of Kepler, NASA's observatory to find Earth-sized planets within the habitable zone of stars, are well matched to the timescales and amplitudes of accretion disk variability in cataclysmic variables.…
We present our photometric studies of the newly discovered optical transient, OT J012059.6+325545, which underwent a large outburst between 2010 November and 2011 January. The amplitude of the outburst was about 8 mag. We performed…
The population of non magnetic cataclysmic variables evolving under the influence of a circumbinary disk is investigated for systems above the upper edge of the period gap at orbital periods greater than 2.75hr. For a fractional mass input…
We observed the 2015 July-August long outburst of V1006 Cyg and established this object to be an SU UMa-type dwarf nova in the period gap. Our observations have confirmed that V1006 Cyg is the second established object showing three types…