J/MNRAS/502/1299 SuperWASP variable stars (Thiemann+, 2021)
SuperWASP variable stars: classifying light curves using citizen science.
Thiemann H.B., Norton A.J., Dickinson H.J., Mcmaster A., Kolb U.C.
<Mon. Not. R. Astron. Soc., 502, 1299-1311 (2021)>
=2021MNRAS.502.1299T 2021MNRAS.502.1299T (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Milky Way ; Stars, double and multiple ;
Optical
Keywords: catalogues - surveys - binaries: general - stars: variables: general
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 >500000 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.
Description:
SuperWASP (Pollacco et al. 2006Ap&SS.304..253P 2006Ap&SS.304..253P) surveyed almost the
entire night sky using two identical observatories in La Palma, Canary
Islands, and Sutherland, South Africa. Each robotic observatory
consisted of eight cameras each with a 14cm aperture and a
7.8x7.8deg2 field of view, allowing for a total sky coverage of
∼500deg2 per exposure. The survey excludes the Galactic plane where
the large pixel scale of 16.7arcsec/pixel prevents separation of
signals from individual stars in this dense stellar region. SuperWASP
observations were reduced using the pipeline described in Pollacco et
al. (2006Ap&SS.304..253P 2006Ap&SS.304..253P). Over the course of ∼2800 nights between
2004 and 2013, SuperWASP accumulated ∼16 million images containing
∼580 billion data points corresponding to ∼31 million unique stars
(Norton 2018RNAAS...2..216N 2018RNAAS...2..216N). The SuperWASP data set therefore
provides a high cadence and long baseline of observations for more
than 30 million stars with magnitudes between V=8-15.
SVS launched on 2018 September 5, with the aim of classifying the
output of the SuperWASP Periodicity Catalogue (Norton
2018RNAAS...2..216N 2018RNAAS...2..216N). The aim of SVS is threefold: to identify rare
variable stars, to identify populations of variable stars in order to
probe the extremes and trends of each population, and to facilitate
the future development of a web portal in order to give researchers
and the public access to the output of this project.
We constructed the SVS project using the Zooniverse project builder
platform (www.zooniverse.org/lab), creating a classification task,
tutorial, and 'Field Guide' that provides example light curves and
guidance for classification.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 50 301 Sample from 301 previously unidentified stellar
variables and related characteristics, not
including rotators and unknown variables
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 25 A25 --- Name Star name (1SWASPJHHMMSS.ss+DDMMSS.s)
27- 34 A8 --- Type Variable type (1)
36- 41 F6.2 d Periodd Period (in days)
43- 50 E8.3 s Periods Period (in seconds)
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Note (1): Type as follows:
EA/EB = detached and semidetached eclipsing binary systems that display
periodic changes in brightness. This category includes Algol (EA)
and Beta Lyrae (EB) eclipsing binaries. Two eclipses per cycle
may be distinguished, often of different depth, with clear
boundaries to the eclipses. (192/301)
EW = contact-eclipsing and near-contact eclipsing binary systems that
display periodic changes in brightness. This category includes
W Ursae Majoris (EW) type eclipsing binaries. Brightness variation
is continuous and the eclipses are often of similar depth,
resulting in half the orbital period often being identified
instead of the true period. (40/301)
Pulsators = stars that display periodic changes in brightness due to changes
in the star's size and luminosity as its outer layers expand and
contract in a regular manner. This category includes RR Lyrae,
δ Scuti, Cepheid variables, and Mira variables. Light curves
are often asymmetric with a steeper rise and shallower fall in
brightness. (69/301)
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 27-Oct-2023