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Related papers: EX Draconis: Using Eclipses to Separate Outside-In…

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We present the Transiting Exoplanet Surveying Satellite (TESS) light curve of the intermediate polar YY Draconis (YY Dra, also known as DO Dra). The power spectrum indicates that while there is stream-fed accretion for most of the…

We report on the analysis of high-speed photometry of the dwarf-nova HS1804+67 through its outburst cycle with eclipse mapping techniques. Eclipse maps show evidences of the formation of a spiral structure in the disc at the early stages of…

Astrophysics · Physics 2007-05-23 Raymundo Baptista , M. S. Catalan

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 present the results of an analysis of data covering 1.5 years of the dwarf nova V447 Lyr. We detect eclipses of the accretion disk by the mass donating secondary star every 3.74 hrs which is the binary orbital period. V447 Lyr is…

Solar and Stellar Astrophysics · Physics 2015-06-05 Gavin Ramsay , John K. Cannizzo , Steve B. Howell , Matt A. Wood , Martin Still , Thomas Barclay , Alan Smale

Observations at high spectral and temporal resolution are presented of the dwarf nova EX Dra in outburst. The disk seen in the He I line reconstructed by Doppler tomography shows a clear two-armed spiral pattern pointing to spiral shocks in…

Astrophysics · Physics 2007-05-23 V. Joergens , H. C. Spruit , R. G. M. Rutten

Detached eclipsing binaries allow stellar masses and radii to be measured with unrivalled accuracy. While inspecting light curves obtained with the Transiting Exoplanet Survey Satellite (TESS), we noticed that the A0 III star $\alpha$ Dra…

Solar and Stellar Astrophysics · Physics 2019-10-30 Timothy R. Bedding , Daniel R. Hey , Simon J. Murphy

Eclipsing planetary systems give us an important window on extrasolar planet atmospheres. By measuring the depth of the secondary eclipse, when the planet moves behind the star, we can estimate the strength of the thermal emission from the…

Astrophysics · Physics 2009-11-13 Heather A. Knutson , David Charbonneau , Drake Deming , L. Jeremy Richardson

EX Lup is the prototype of the EXor class of eruptive young stars. These objects show optical outbursts which are thought to be related to runaway accretion onto the star. In a previous study we observed in-situ crystal formation in the…

RXTE observed 20 eclipse egresses of the intermediate polar XY Ari in order to study the size and structure of the X-ray emitting accretion regions. The spin-phase averaged egress lasts 26 s, implying a white dwarf radius of 4.3-7.0 10^8…

Astrophysics · Physics 2015-06-24 Coel Hellier

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

The unprecedented extent of coverage provided by Kepler observations recently revealed outbursts in two hydrogen-atmosphere pulsating white dwarfs (DAVs) that cause hours-long increases in the overall mean flux of up to 14%. We have…

We observed the 2002 October-November outburst of the dwarf nova CW Mon. The outburst showed a clear signature of a premaximum halt, and a more rapid decline after reaching the outburst maximum. On two separate occasions, during the…

We present XMM-Newton observations of the eclipsing polar EP Dra which cover nearly 3 binary orbital cycles. The X-ray and UV data show evidence for a prominent dip before the eclipse which is due to the accretion stream obscuring the…

Astrophysics · Physics 2009-11-10 Gavin Ramsay , C. M. Bridge , Mark Cropper , K. O. Mason , F. A. Cordova , W. Priedhorsky

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…

High Energy Astrophysical Phenomena · Physics 2017-04-12 J. -M. Hameury , J. -P. Lasota , C. Knigge , E. G. Körding

Context. Although the disc instability model is widely accepted as the explanation for dwarf nova outbursts, it is still necessary to confront its predictions to observations because much of the constraints on angular momentum transport in…

Solar and Stellar Astrophysics · Physics 2020-04-08 J. -M. Hameury , C. Knigge , J. -P. Lasota , F. -J. Hambsch , R. James

We observed an X-ray selected, deeply eclipsing cataclysmic variable IR Com (=S 10932). We detected an outburst occurring on 1996 January 1. The light curve of the outburst closely resembled that of a normal outburst of an SU UMa-type dwarf…

Astrophysics · Physics 2015-06-24 Taichi Kato , Hajime Baba , Daisaku Nogami

We present the analysis of optical photometric and spectroscopic observations of two non-magnetic cataclysmic variables, namely CRTS J080846.2+313106 and V416 Dra. CRTS J080846.2+313106 has been found to vary with a period of…

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

Using BATSE and RXTE observations from 1991 April to 2001 August we have detected 71 outbursts from 82 periastron passages of EXO 2030+375, a 42-second transient X-ray pulsar with a Be star companion, including several outbursts from 1993…

Astrophysics · Physics 2009-11-07 Colleen A. Wilson , Mark H. Finger , M. J. Coe , Silas Laycock , J. Fabregat

Extreme outbursts in young stars may be a common stage of pre-main-sequence stellar evolution. These outbursts, caused by enhanced accretion and accompanied by increased luminosity, can also strongly impact the evolution of the…