First photometric investigation of two short-period eclipsing binaries ASAS J105115-6032.1 and GDS J1056047-604149

ABSTRACT We present the first analysis of results from the SuperWASP variable stars Zooniverse project, which is aiming to classify 1.6 million phase-folded light curves of candidate stellar variables observed by the SuperWASP all sky survey with periods detected in the SuperWASP periodicity catalogue. The resultant data set currently contains >1 million classifications corresponding to >500 000 object–period combinations, provided by citizen–scientist volunteers. Volunteer-classified light curves have ∼89 per cent accuracy for detached and semidetached eclipsing binaries, but only ∼9 per cent accuracy for rotationally modulated variables, based on known objects. We demonstrate that this Zooniverse project will be valuable for both population studies of individual variable types and the identification of stellar variables for follow-up. We present preliminary findings on various unique and extreme variables in this analysis, including long-period contact binaries and binaries near the short-period cut-off, and we identify 301 previously unknown binaries and pulsators. We are now in the process of developing a web portal to enable other researchers to access the outputs of the SuperWASP variable stars project.

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The Short-Period Group of Eclipsing Binaries with Properties Similar to the Classical RS CVn Group

Photometric and Spectroscopic Binary Systems ◽

10.1007/978-94-009-8486-8_15 ◽

1981 ◽

pp. 331-360 ◽

Cited By ~ 10

Author(s):

L. Milano

Keyword(s):

Eclipsing Binaries ◽

Short Period

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The Evolutionary Status of Short-Period RS CVn and Related W UMa Eclipsing Binaries

International Astronomical Union Colloquium ◽

10.1017/s0252921100096482 ◽

1983 ◽

Vol 71 ◽

pp. 463-464 ◽

Cited By ~ 1

Author(s):

G. Russo ◽

L. Milano ◽

S. Mancuso

Keyword(s):

Eclipsing Binaries ◽

Evolutionary Status ◽

Type Activity ◽

Rs Cvn Stars ◽

Short Period ◽

Solar Type

Among the RS CVn stars showing solar-type activity, with spectral types ranging from F to K and total masses up to 4 M⊙, there are two peculiar groups with period less than one day:a)agroup with components well inside their Roche lobes (Short-Period-Group, hereinafter SPG) and b) a group with their components in a thin or marginal degree of contact, with lightcurves of W UMa-W type (hereinafter WWG).

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A survey for high-mass eclipsing binaries

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2953 ◽

2019 ◽

Vol 490 (4) ◽

pp. 5147-5173

Author(s):

F Pozo Nuñez ◽

R Chini ◽

A Barr Domínguez ◽

Ch Fein ◽

M Hackstein ◽

...

Keyword(s):

Eclipsing Binaries ◽

Light Curves ◽

High Mass ◽

System Component ◽

Fundamental Parameters ◽

Average Value ◽

Short Period ◽

Orbital Periods ◽

Photometric Monitoring ◽

Period System

ABSTRACT We report results from a search for Galactic high-mass eclipsing binaries. The photometric monitoring campaign was performed in Sloan r and i with the robotic twin refractor RoBoTT at the Universitätssternwarte Bochum in Chile and complemented by Johnson UBV data. Comparison with the SIMBAD data base reveals 260 variable high-mass stars. Based on well-sampled light curves, we discovered 35 new eclipsing high-mass systems and confirm the properties of six previously known systems. For all objects, we provide the first light curves and determine orbital periods through the Lafler–Kinman algorithm. Apart from GSC 08173-0018 and Pismis 24-13 ($P = 19.47\, d$ and $20.14\, d$) and the exceptional short-period system TYC 6561-1765-1 ($P = 0.71\, d$), all systems have orbital periods between 1 and 9 d. We model the light curves of 26 systems within the framework of the Roche geometry and calculate fundamental parameters for each system component. The Roche lobe analysis indicates that 14 systems have a detached geometry, while 12 systems have a semidetached geometry; seven of them are near-contact systems. The deduced mass ratios q = M2/M1 reach from 0.4 to 1.0 with an average value of 0.8. The similarity of masses suggests that these high-mass binaries were created during the star formation process rather than by tidal capture.

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Orbital parameters and period variation studies of the short-period eclipsing binaries FG Sct, VZ Lib and VZ Psc

Research in Astronomy and Astrophysics ◽

10.1088/1674-4527/19/7/97 ◽

2019 ◽

Vol 19 (7) ◽

pp. 097 ◽

Cited By ~ 2

Author(s):

Qiang Yue ◽

Li-Yun Zhang ◽

Xian-Ming L. Han ◽

Hong-Peng Lu ◽

Liu Long ◽

...

Keyword(s):

Eclipsing Binaries ◽

Period Variation ◽

Orbital Parameters ◽

Short Period

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Differential rotation in convective envelopes: constraints from eclipsing binaries

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2983 ◽

2019 ◽

Vol 491 (1) ◽

pp. 690-707 ◽

Cited By ~ 1

Author(s):

Adam S Jermyn ◽

Jamie Tayar ◽

Jim Fuller

Keyword(s):

Differential Rotation ◽

Orbital Period ◽

Binary Systems ◽

Rotation Period ◽

Eclipsing Binaries ◽

Rotation Periods ◽

Short Period ◽

Orbital Periods ◽

The Difference ◽

Surface Convection

ABSTRACT Over time, tides synchronize the rotation periods of stars in a binary system to the orbital period. However, if the star exhibits differential rotation, then only a portion of it can rotate at the orbital period, so the rotation period at the surface may not match the orbital period. The difference between the rotation and orbital periods can therefore be used to infer the extent of the differential rotation. We use a simple parametrization of differential rotation in stars with convective envelopes in circular orbits to predict the difference between the surface rotation period and the orbital period. Comparing this parametrization to observed eclipsing binary systems, we find that in the surface convection zones of stars in short-period binaries there is very little radial differential rotation, with |r∂rln Ω| < 0.02. This holds even for longer orbital periods, though it is harder to say which systems are synchronized at long periods, and larger differential rotation is degenerate with asynchronous rotation.

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Time-Resolved Spectroscopy of Short Period RS CVn Systems

International Astronomical Union Colloquium ◽

10.1017/s0252921100018145 ◽

1993 ◽

Vol 137 ◽

pp. 392-394

Author(s):

C. Lázaro ◽

M.J. Arévalo

Keyword(s):

Spectral Type ◽

Main Sequence ◽

Eclipsing Binaries ◽

Time Resolved ◽

Binary Model ◽

Short Period ◽

First Results ◽

Orbital Phase ◽

Phase Resolution ◽

Orbital Periods

AbstractWe have initiated a programme of spectroscopic observations of RS CVn short-period group, with orbital phase resolution. The systems of this group are all eclipsing binaries with both components at the Main Sequence, and most of them have similar spectral type components. The high rotational velocities and their short orbital periods (less than 1 day) hinder the spectroscopic study of these stars. We presents the first results yielded by Hα line observations of the systems XY UMa and WY Cnc. Both systems were observed during 1991 with reasonably wide orbital phase coverage. The analysis of the spectra is made by comparison with a binary model, constructed from the observed spectra of normal stars of the same spectral type as the RS CVn system components. The model accounts for the partial contribution of each component at any orbital phase within eclipses.

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The absence of a short period in the WN5 star EZ Canis Majoris

Symposium - International Astronomical Union ◽

10.1017/s0074180900201599 ◽

1995 ◽

Vol 163 ◽

pp. 56-57

Author(s):

Igor I. Antokhin ◽

Jean-François Bertrand ◽

Robert Lamontagne ◽

Anthony F.J. Moffat

Keyword(s):

Third Harmonic ◽

The Third ◽

Short Period ◽

Photometric Investigation ◽

The One

Several suggestion have been put forward to explain the 3.d766 periodicity of EZ CMa (WR6): (i) WR+c system; (ii) rotating single WR star; (iii) pulsations (non—radial (NRP) or radial) with frequency reduced by some kind of filtering in the wind. In this paper, we report on a photometric investigation based on a long continuous observing run, in an attempt to verify whether EZ CMa does in fact show a unique periodicity. In particular, this work was motivated by the claim by Gosset & Vreux (1987), based on the data from Lamontagne et al. (1986, hereafter LML), that EZ CMa may have a shorter period besides the one at 3.d766, a frequency close to but not equal to the third harmonic of the 3.d766 period.

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