Related papers: MOST photometry and DDO spectroscopy of the eclips…
V471 Tau is a post-common-envelope binary consisting of an eclipsing DA white dwarf and a K-type main-sequence star in the Hyades star cluster. We analyzed publicly available photometry and spectroscopy of V471 Tau to revise the stellar and…
V471 Tauri, an eclipsing system consisting of a hot DA white dwarf (WD) and a dK2 companion in a 12.5-hour orbit, is the prototype of the pre-cataclysmic binaries. The late-type component is magnetically active, due to its being constrained…
Observations of the eclipsing binary system V471 Tau show that the time of the primary eclipses varies in an apparent periodic way. With growing evidence that the magnetically active K2 dwarf component might be responsible for driving the…
We have carried out an analysis of about 160 eclipse timings spanning over 30 years of the Hyades eclipsing binary V471 Tauri that shows a long-term quasi-sinusoidal modulation of its observed eclipse arrival times. The O-Cs have been…
We present surface spot maps of the K2V primary star in the pre-cataclysmic variable binary system, V471 Tau. The spot maps show the presence of large high latitude spots located at the sub-white dwarf longitude region. By tracking the…
V471 Tauri, a white dwarf--red dwarf eclipsing binary in the Hyades, is well known for stimulating development of common envelope theory, whereby novae and other cataclysmic variables form from much wider binaries by catastrophic orbit…
We scrutinize the red dwarf component in the eclipsing binary system V471 Tau in order to unravel relations between different activity layers from the stellar surface through the chromosphere up to the corona. We aim at studying how the…
We report the discovery of a relatively bright eclipsing binary system, which consists of a white dwarf and a main sequence K7 star with clear signs of chromospheric and spot activity. The light curve of this system shows $\sim0.2$mag…
We have used the GHRS onboard the HST to obtain Lyman-alpha spectra of the hot white-dwarf (WD) component of the short-period eclipsing DA+dK2 pre-cataclysmic binary V471 Tauri, a member of the Hyades star cluster. Radial velocities of the…
We present time-series spectroscopy and photometry of Gaia DR2 6097540197980557440, a new deeply-eclipsing hot subdwarf B (sdB) + M dwarf (dM) binary. We discovered this object during the course of the Eclipsing Reflection Effect Binaries…
We report on both high-precision photometry from the MOST space telescope and ground-based spectroscopy of the triple system delta Ori A consisting of a binary O9.5II+early-B (Aa1 and Aa2) with P = 5.7d, and a more distant tertiary (O9 IV P…
We have carried out an analysis of the HST STIS archival spectra of the magnetic white dwarf in the Hyades eclipsing-spectroscopic, post-common envelope binary V471 Tauri, time resolved on the orbit and on the X-ray rotational phase of the…
We report on high-speed eclipse photometry of the dwarf nova V2051 Oph while it was in a low brightness state, at B ~ 16.2 mag. In comparison to the average IUE spectra, the ultraviolet continuum and emission lines appear reduced by factors…
We present an analysis of a new, detached, double-lined eclipsing binary system with K7 Ve components, discovered as part of the University of New South Wales Extrasolar Planet Search. The object is significant in that only 6 other binary…
Although triple systems are common, their orbital dynamics and stellar evolution remain poorly understood. We investigated the V1371 Tau system using TESS photometry, multi-epoch spectroscopy, and recent interferometric data, confirming it…
We report our discovery of an extremely rare, low mass, quadruple-lined spectroscopic binary BD-22 5866 (=NLTT 53279, integrated spectral type = M0 V), found during an ongoing search for the youngest M dwarfs in the solar neighborhood. From…
Chandra Low Energy Transmission Grating Spectrograph observations of the pre-cataclysmic binary V471 Tau have been used to estimate the C/N abundance ratio of the K dwarf component for the first time. While the white dwarf component…
We analyze spectropolarimetric data of the pre-cataclysmic variable binary system V471 Tau obtained with ESPaDOnS at the Canada-France-Hawaii Telescope in two observational campaigns (in Nov/Dec 2004 and Dec 2005). Using Zeeman-Doppler…
HS0907+1902 was recently discovered to be one of a handful of deeply eclipsing dwarf novae with periods longward of the 2 -- 3 hr `gap'. This paper presents orbit-resolved spectra and time series photometry of an eclipse. The apparent…
We have used 605 days of photometric data from the Kepler spacecraft to study KIC 6614501, a close binary system with an orbital period of 0.15749747(25) days (3.779939 hours), that consists of a low-mass subdwarf B (sdB) star and a white…