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Related papers: Superhumps and their Amplitudes

200 papers

We report results of an extensive world-wide observing campaign devoted to a very active dwarf nova star - IX Draconis. We investigated photometric behaviour of the system to derive its basic outburst properties and understand peculiarities…

Solar and Stellar Astrophysics · Physics 2015-06-12 M. Otulakowska-Hypka , A. Olech , E. de Miguel , A. Rutkowski , R. Koff , K. Bakowska

We present an analysis of CCD photometric observations of the eclipsing novalike cataclysmic variable DW UMa obtained in two different luminosity states: high and intermediate. The star presents eclipses with very different depth: ~1.2 mag…

Astrophysics · Physics 2009-11-10 V. Stanishev , Z. Kraicheva , H. M. J. Boffin , V. Genkov , C. Papadaki , S. Carpano

We report the results of a worldwide campaign to observe WZ Sagittae during its 2001 superoutburst. After a 23-year slumber at V=15.5, the star rose within 2 days to a peak brightness of 8.2, and showed a main eruption lasting 25 days. The…

Superoutbursts in WZ Sge-type dwarf novae (DNe) are characterized by both early superhumps and ordinary superhumps originating from the 2:1 and 3:1 resonances, respectively. However, some WZ Sge-type DNe show a superoutburst lacking early…

A new method for analyzing complex superhump light curves for the 2001 outburst of WZ Sagittae is proposed. The complexity arises because intrinsically time-varying and non-axisymmetric distributions of superhump light sources are coupled…

Astrophysics · Physics 2015-06-24 Y. Osaki

We report an analysis of photometric behaviour of DI UMa, an extremely active dwarf nova. The observational campaign (completed in 2007) covers five superoutbursts and four normal outbursts. We examined principal parameters of the system to…

Astrophysics · Physics 2009-11-13 A. Rutkowski , A. Olech , M. Wiśniewski , P. Pietrukowicz , J. Pala , R. Poleski

We show that if the dwarf-nova disc instability model includes the effects of heating by stream impact and tidal torque dissipation in the outer disc, the calculated properties of dwarf-nova outbursts change considerably, and several…

Astrophysics · Physics 2009-10-31 Valentin Buat-Menard , Jean-Marie Hameury , Jean-Pierre Lasota

We include the tidal instability due to the 3:1 resonance in the disc instability model developed by Hameury et al. (1998) and modified by Buat-Menard et al. (2001). We confirm earlier results by Osaki (1989) that the tidal instability can…

Astrophysics · Physics 2009-11-07 Valentin Buat-Menard , Jean-Marie Hameury

We present high-time-resolution photometry and phase-resolved spectroscopy of the short-period ($P_\mathrm{orb} = 80.52\,\mathrm{min}$) cataclysmic variable SDSS J123813.73-033933.0, observed with the $\mathit{Hubble}$ $\mathit{Space}$…

We report photometry of 1RXS J232953.9+062814, a recently discovered dwarf nova with a remarkably short 64.2-minute orbital period. In quiescence, the star's light curve is that of a double sinusoid, arising from the "ellipsoidal"…

We present observations of the intranight brightness variability of CR Boo, a member of the AM CVn stars group. The observational data are obtained with the 2m telescope of the Rozhen National Astronomical Observatory and the 60 cm…

Solar and Stellar Astrophysics · Physics 2023-08-16 Daniela Boneva , Georgi Latev , Svetlana Boeva , Krasimira Yankova , Radoslav Zamanov

Archival data on permanent superhump systems are compiled to test the thermal stability of their accretion discs. We find that their discs are almost certainly thermally stable as expected. This result confirms Osaki's suggestion (1996)…

Astrophysics · Physics 2009-10-31 A. Retter , T. Naylor

We present an analysis of all available time-resolved photometry from the literature and new light curves obtained in 2013-2014 for the old nova RR Pictoris. The well-known hump light curve phased with the orbital period reveals significant…

Solar and Stellar Astrophysics · Physics 2017-12-27 I. Fuentes-Morales , N. Vogt , C. Tappert , L. Schmidtobreick , F. -J. Hambsch , M. Vuĉkovíc

[Abridged] We present more than 4 years of Swift X-ray observations of the 2013 superoutburst, subsequent decline and quiescence of the WZ Sge-type dwarf nova SSS J122221.7-311525 (SSS122222) from 6 days after discovery. Only a handful of…

High Energy Astrophysical Phenomena · Physics 2018-03-14 V. V. Neustroev , K. L. Page , E. Kuulkers , J. P. Osborne , A. P. Beardmore , C. Knigge , T. Marsh , V. F. Suleimanov , S. V. Zharikov

We consider discs that orbit a central object and are tidally perturbed by a circular orbit companion. Such discs are sometimes subject to an eccentric instability due to the effects of certain resonances. Eccentric instabilities may be…

Solar and Stellar Astrophysics · Physics 2015-05-18 Stephen H. Lubow

We have summarized the current understanding and recently obtained findings about WZ Sge-type dwarf novae. We also reviewed the historical development of the understanding of these objects, provided the modern criteria, and reviewed the…

Solar and Stellar Astrophysics · Physics 2015-09-30 Taichi Kato

We demonstrate that measurable vertical structure can be excited in the accretion disc of a close binary system by a dipolar magnetic field centred on the secondary star. We present the first high resolution hydrodynamic simulations to show…

Astrophysics · Physics 2009-11-07 James Murray , Dalia Chakrabarty , Graham Wynn , Louisa Kramer

As 2 black holes bound to each other in a close binary approach merger their inspiral time becomes shorter than the characteristic inflow time of surrounding orbiting matter. Using an innovative technique in which we represent the changing…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Scott C. Noble , Bruno C. Mundim , Hiroyuki Nakano , Julian H. Krolik , Manuela Campanelli , Yosef Zlochower , Nicolás Yunes

A thermal/viscous instability of the accretion disc arising when hydrogen is partially ionized is the most popular explanation of the outbursts of both dwarf novae (DN) and soft X-ray transients (SXT). During an outburst, the disc expands…

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

We report unfiltered CCD photometry of the eclipsing dwarf nova SDSS J093249.57+472523.0 obtained during its first confirmed outburst in 2011 March. The outburst amplitude was at least 3.0 magnitudes above mean quiescence and it lasted at…

Solar and Stellar Astrophysics · Physics 2012-02-06 Jeremy Shears , Steve Brady , Shawn Dvorak , Enrique de Miguel , Etienne Morelle , Arto Oksanen , Richard Sabo