J/A+A/635/A74 Transiting planet WASP-76 (Southworth+, 2020)
A multiplicity study of transiting exoplanet host stars.
II. Revised properties of transiting planetary systems with companions.
Southworth J., Bohn A.J., Kenworthy M.A., Ginski C., Mancini L.
<Astron. Astrophys. 635, A74 (2020)>
=2020A&A...635A..74S 2020A&A...635A..74S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Photometry ; Optical
Keywords: planetary systems - stars: fundamental parameters -
stars: individual: WASP-76
Abstract:
Binarity is a widespread phenomenon around solar-type stars, including
the host stars of transiting extrasolar planets.
We performed a detailed study of six transiting planetary systems with
relatively bright stars close enough to affect observations of these
systems. These contaminants were characterised in a companion work.
We used theoretical spectra to propagate the observed K-band light
ratios into the optical passbands used to observe these systems. Light
curves were analysed whilst taking the contaminating light and its
uncertainty into account. We present and applied a method to correct
the velocity amplitudes of the host stars for the presence of
contaminating light. Results: We determined the physical properties of
six systems (WASP-20, WASP-70, WASP-8, WASP-76, WASP-2, and WASP-131)
whilst accounting for contaminating light. In the case of WASP-20, the
measured physical properties are very different for the three
scenarios considered: ignoring binarity, planet transits brighter
star, and planet transits fainter star. In the other five cases, our
results are very similar to those obtained when neglecting
contaminating light. We used our results to determine the mean
correction factors to planet radius, <XR>, mass, , and density,
<Xrho>, caused by nearby objects. We find <XR≥1.009±0.045,
which is smaller than literature values because we were able to reject
the possibility that the planet orbits the fainter star in all but one
case. We find <XM≥1.031±0.019, which is larger than <XR>
because of the strength of the effect of contaminating light on the
radial velocity measurements of the host star. We find
<Xrho≥0.995±0.046: the small size of this correction is due to
two effects: the corrections on planet radius and mass partially
cancel; and some nearby stars are close enough to contaminate the
light curves of the system but not radial velocities of he host star.
These corrections can be applied to samples of transiting hot Jupiters
to statistically remove biases due to light contamination.
We conclude that binarity of planet host stars is important for the
small number of transiting hot Jupiters with a very bright and close
nearby star, but it has only a small effect on population-level
studies of these objects.
Description:
One light curve of a transit of the extrasolar planetary system
WASP-76 was presented, obtained using the 1.23m telescope at Calar
Alto Observatory, Spain. The paper also used data from the Transiting
Exoplanet Space Satellite (TESS) which are available from the NASA
archive. The filter used for the WASP-76 data was Cousins R and the
telescope was defocussed to increase the photometric precision of the
data.
Objects:
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RA (2000) DE Designation(s)
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01 46 31.86 +02 42 02.0 WASP-76 = 1SWASP J014631.86+024202.0 = TYC 32-111-1
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
lc.dat 35 362 Differential photometry of WASP-76
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See also:
J/MNRAS/396/1023 : Transiting planetary system WASP-5 (Southworth+, 2009)
J/MNRAS/399/287 : Transiting planetary system WASP-4 (Southworth+, 2009)
J/ApJ/707/167 : Transiting planetary system WASP-18 (Southworth+, 2009)
J/MNRAS/408/1680 : Transiting planetary system WASP-2 (Southworth+, 2010)
J/A+A/527/A8 : Transiting planetary system WASP-7 (Southworth+, 2011)
J/MNRAS/420/2580 : Four transits of HAT-P-13 (Southworth+, 2012)
J/MNRAS/422/3099 : Transits of HAT-P-5 (Southworth+, 2012)
J/MNRAS/426/1338 : Transiting planetary system WASP-17 (Southworth+, 2012)
J/MNRAS/434/1300 : Planetary systems WASP-15, WASP-16 (Southworth+, 2013)
J/MNRAS/444/776 : WASP-24, WASP-25 and WASP-26 (Southworth+, 2014)
J/MNRAS/447/711 : Transiting planetary system WASP-103 (Southworth+, 2015)
J/MNRAS/454/3094 : Transiting planetary system WASP-57 (Southworth+, 2016)
J/MNRAS/457/4205 : WASP-22, WASP-41, WASP-42 and WASP-55 (Southworth+, 2016)
J/AJ/153/191 : Transiting planetary system GJ 1132 (Southworth+, 2017)
J/MNRAS/490/4230 : Transiting planet WASP-4b (Southworth+, 2019)
J/A+A/635/A73 : Multiplicity study of transiting exoplanet hosts. I.
(Bohn+, 2020)
J/MNRAS/515/3212 : Transiting planet HATS-18b (Southworth+, 2022)
J/MNRAS/521/3405 : Low-mass eclipsing binaries (Jennings+, 2023)
Byte-by-byte Description of file: lc.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d BJD Barycentric Julian Date for the midpoint of
observation (TDB)
16- 25 F10.7 mag mag Differential R-band magnitude magnitude
27- 35 F9.7 mag e_mag Measurement error of the differential magnitude
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Acknowledgements:
John Southworth, taylorsouthworth(at)gmail.com
References:
Bohn et al., Paper I 2020A&A...635A..73B 2020A&A...635A..73B, Cat. J/A+A/635/A73
(End) John Southworth [Keele Univ., UK], Patricia Vannier [CDS] 08-Jul-2023