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

AbstractThe characterization of short-period detached low-mass binaries, by the determination of their physical and orbital parameters, reveal the most precise basic parameters of low-mass stars. Particularly, when photometric and spectroscopic data of eclipsing binaries (EBs) are combined. Recently, 16 new low-mass EBs were discovered by the WFCAM Transit Survey (WTS), however, only three of them were fully characterized. Therefore, new spectroscopic data were already acquired with the objective to characterize five new detached low-mass EBs discovered in the WTS, with short periods between 0.59 and 1.72 days. A preliminary analysis of the radial velocity and light curves was performed, where we have derived orbital separations of 2.88 to 6.69 R⊙, and considering both components, we have found stellar radii ranging from 0.40 to 0.80 R⊙, and masses between 0.24 and 0.71 M⊙. In addition to the determination of the orbital parameters of these systems, the relation between mass, radius and orbital period of these objects can be investigated in order to study the mass-radius relationship and the radius anomaly in the low main-sequence.

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SuperWASP variable stars: classifying light curves using citizen science

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab140 ◽

2021 ◽

Vol 502 (1) ◽

pp. 1299-1311

Author(s):

Heidi B Thiemann ◽

Andrew J Norton ◽

Hugh J Dickinson ◽

Adam McMaster ◽

Ulrich C Kolb

Keyword(s):

Variable Stars ◽

Eclipsing Binaries ◽

Light Curves ◽

Data Set ◽

Resultant Data ◽

Sky Survey ◽

Short Period ◽

Contact Binaries ◽

Analysis Of Results

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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Twin stars as tracers of binary evolution in the Kepler era

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab343 ◽

2021 ◽

Author(s):

Sara Bulut ◽

Baris Hoyman ◽

Ahmet Dervisoglu ◽

Orkun Özdarcan ◽

Ömür Cakilrli

Keyword(s):

High Resolution ◽

Internal Structure ◽

Spectroscopic Analysis ◽

Independent Method ◽

Eclipsing Binaries ◽

Physical Parameters ◽

Evolutionary Status ◽

Mass Ratio ◽

Orbital Parameters ◽

Binary Evolution

Abstract We present results of the combined photometric and spectroscopic analysis of four systems, which are eclipsing binaries with a twin–component (mass ratio q ≃ 1). These are exceptional tools to provide information for probing the internal structure of stars. None of the systems were previously recognized as twin binaries. We used a number of high–resolution optical spectra to calculate the radial velocities and later combined them with photometry to derive orbital parameters. Temperatures and metallicities of systems were estimated from high-resolution spectra. For each binary, we obtained a full set of orbital and physical parameters, reaching precision below 3 per cent in masses and radii for whole pairs. By comparing our results with PARSEC and MIST isochrones, we assess the distance, age and evolutionary status of the researched objects. The primary and/or secondary stars of EPIC 216075815 and EPIC 202843107 are one of the cases where asteroseismic parameters of δ Sct and γ Dor pulsators were confirmed by an independent method and rare examples of the twin–eclipsing binaries, therefore the following analyses and results concern the pulsating nature of the components.

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

New Astronomy ◽

10.1016/j.newast.2021.101756 ◽

2022 ◽

pp. 101756

Author(s):

Fu-Xing Li ◽

Nian-Ping Liu ◽

Boonrucksar Soonthornthum ◽

Thawicharat Sarotsakulchai

Keyword(s):

Eclipsing Binaries ◽

Short Period ◽

Photometric Investigation

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Analysis of Ca+ K plage area for short period variation

Journal of Astrophysics and Astronomy ◽

10.1007/bf02715073 ◽

1989 ◽

Vol 10 (4) ◽

pp. 381-389

Author(s):

Jagdev Singh ◽

S. K. Jain

Keyword(s):

Period Variation ◽

Short Period

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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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