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Related papers: The dwarf nova SS Cygni: what is wrong?

200 papers

We present computations for the accretion disk limit cycle model in an attempt to explain the empirical relation for dwarf nova outbursts between the peak visual absolute magnitude and orbital period found by Warner. For longer period…

Astrophysics · Physics 2009-10-30 John K. Cannizzo

In a recent publication, we introduce the lift force as a common source to accretion disk tilt that is likely relevant to accretion disk systems. Lift is generated by slightly different supersonic gas stream speeds flowing over and under…

Solar and Stellar Astrophysics · Physics 2015-05-20 M. M. Montgomery

We report astrometric parallaxes for three well known dwarf novae obtained using the Fine Guidance Sensors on the Hubble Space Telescope. We found a parallax for SS Aurigae of Pi = 5.00 +/- 0.64 mas, for SS Cygni we found Pi = 6.02 +/- 0.46…

We report the analysis of 22 B-band light curves of the dwarf nova V4140 Sgr obtained with SOI/SOAR during two nights along the decline of a superoutburst in 2006 Sep 12-24 and in quiescence over 50 days following the superoutburst.…

Solar and Stellar Astrophysics · Physics 2016-09-21 Raymundo Baptista , Bernardo W. Borges , Alexandre S. Oliveira

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…

Astrophysics · Physics 2007-05-23 Jean-Marie Hameury , Jean-Pierre Lasota , Brian Warner

We study the stability of disc accretion in the recurrent nova RS Ophiuchi. We construct a one-dimensional time-dependent model of the binary-disc system, which includes viscous heating and radiative cooling and a self-consistent treatment…

High Energy Astrophysical Phenomena · Physics 2015-05-30 R. D. Alexander , G. A. Wynn , A. R. King , J. E. Pringle

U Gem is unique in having a direct measurement of K1 = 107 +- 2 km/s, Long et al. 1999). We present high-resolution optical spectra of the dwarf nova U Gem in quiescence taken to test the accuracy to which the HST value can be recovered…

Astrophysics · Physics 2009-11-11 E. Unda-Sanzana , T. R. Marsh , L. Morales-Rueda

We obtained three consecutive HST spectroscopic observations of a single superoutburst of the dwarf nova VW Hydri. The spectra cover the beginning, middle, and end of the superoutburst. All of the spectra are dominated by strong absorption…

Astrophysics · Physics 2009-11-13 Jason Merritt , Christopher Night , Edward M. Sion

We show how wavelength-dependent time delays between continuum flux variations of AGN can be used to test the standard black hole-accretion disc paradigm, by measuring the temperature structure $T(R)$ of the gaseous material surrounding the…

Astrophysics · Physics 2009-10-31 Stefan Collier , Kieth Horne , Ignaz Wanders , Bradley M. Peterson

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…

Astrophysics · Physics 2015-06-24 C. Done , J. P. Osborne

Diversity of the X-ray observations of dwarf nova are still not fully understood. I review the X-ray spectral characteristics of dwarf novae during the quiescence in general explained by cooling flow models and the outburst spectra that…

High Energy Astrophysical Phenomena · Physics 2014-03-19 S. Balman

The evidence presented earlier by several authors for the substantial disk eccentricity in dwarf novae during their superoutbursts is shown to result either from errors or from arbitrary, incorrect assumptions. In particular, the evidence…

Solar and Stellar Astrophysics · Physics 2009-04-15 J. Smak

We investigate variations of the mass transfer rate in cataclysmic variables (CVs) that are induced by nova outbursts. The ejection of nova shells leads to a spread of transfer rates in systems with similar orbital period. The effect is…

Astrophysics · Physics 2009-11-07 Ulrich Kolb , Saul Rappaport , Klaus Schenker , Steve Howell

We have discovered that the spectrum of the well-known dwarf nova EM Cyg is contaminated by light from a K2-5V star (in addition to the K-type mass donor star). The K2-5V star contributes approximately 16 per cent of the light from the…

Astrophysics · Physics 2009-10-31 R. C. North , T. R. Marsh , C. K. J. Moran , U. Kolb , R. C. Smith , R. Stehle

The disc instability mechanism (DIM) is widely accepted to account for the transient behaviour of dwarf novae (DNe), which experience short outbursts separated by long quiescence. The duty cycle (the ratio between the outburst duration and…

Solar and Stellar Astrophysics · Physics 2023-08-17 Wei-Min Liu , Long Jiang , Wen-Cong Chen , Xiang-Dong Li

The eruptive cycles of dwarf novae (DN) are thought to be due to a thermal-viscous instability in the accretion disk surrounding the white dwarf (WD). This model has long been known to imply a stress to pressure ratio \alpha ~0.1 in…

Solar and Stellar Astrophysics · Physics 2018-01-17 N. Scepi , G. Lesur , G. Dubus , M. Flock

We examine published observations of dwarf nova oscillations (DNOs) on the rise and decline of outbursts and show that their rates of change are in reasonable agreement with those predicted from the magnetic accretion model. We find…

Astrophysics · Physics 2009-11-13 Brian Warner , Magaretha L. Pretorius

The photometric and spectroscopic evolution of the He/N and very fast Nova Cyg 2008 N2 (V2491 Cyg) is studied in detail. A primary maximum was reached at V=7.45 +/-0.05 on April 11.37 (+/-0.1) 2008 UT, followed by a smooth decline…

Solar and Stellar Astrophysics · Physics 2015-05-19 U. Munari , A. Siviero , S. Dallaporta , G. Cherini , P. Valisa , L. Tomasella

The geometry of the accretion flow in black-hole X-ray binaries in the hard state, in particular the position of the disc inner edge, has been a subject of intense debate in recent years. We address this issue by performing a spectral study…

High Energy Astrophysical Phenomena · Physics 2017-10-18 Rupal Basak , Andrzej A. Zdziarski , Michael Parker , Nazma Islam

We study the optical evolution of the 2015 outburst in V404 Cyg, with emphasis on the peculiar nebular phase and subsequent decay to quiescence. From the decay timescale of the Balmer emission associated with the nebula we measure an…

High Energy Astrophysical Phenomena · Physics 2019-07-10 J. Casares , T. Muñoz-Darias , D. Mata Sanchez , P. A. Charles , M. A. P. Torres , M. Armas Padilla , R. P. Fender , J. Garcia-Rojas