J/A+A/633/A30 Light curves and RVs of WASP-174 (Mancini+, 2020)
The highly inflated giant planet WASP-174b.
Mancini L., Sarkis P., Henning T., Bakos G.A., Bayliss D., Bento J.,
Bhatti W., Brahm R., Csubry Z., Espinoza N., Hartman J., Jordan A.,
Penev K., Rabus M., Suc V., de Val-Borro M., Zhou G., Chen G.,
Damasso M., Southworth J., Tan T.G.
<Astron. Astrophys. 633, A30 (2020)>
=2020A&A...633A..30M 2020A&A...633A..30M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Photometry ;
Radial velocities
Keywords: planetary systems - stars: fundamental parameters -
stars: individual: WASP-174 - techniques: photometric -
techniques: radial velocities - methods: data analysis
Abstract:
The transiting exoplanetary system WASP-174 was reported to be
composed by a main-sequence F star and a giant planet, WASP-174b.
However only an upper limit was placed on the planet mass, and a
highly uncertain planetary radius was determined.
We aim to better characterise both the star and the planet and
precisely measure their orbital and physical parameters.
In order to constrain the mass of the planet, we obtained new
measurements of the radial velocity of the star and joined them with
those from the discovery paper. Photometric data Q1 from the HATSouth
survey and new multi-band, high-quality (precision reached up to
0.37mmag) photometric follow-up observations of transit events were
acquired and analysed for getting accurate photometric parameters. We
fit the model to all the observations, including data from the TESS
space telescope, in two different modes: incorporating the stellar
isochrones into the fit, and using an empirical method to get the
stellar parameters. The two modes resulted to be consistent with each
other.
We confirm the grazing nature of the WASP-174b transits, which is also
corroborated by simultaneously observing the transit through four
optical bands and noting how the transit depth changes due to the
limb-darkening effect. We estimate that 76% of the disk of the planet
actually eclipses the parent star at mid-transit of its transit
events. We find that WASP-174b is a highly-inflated hot giant planet
with a mass of 0.330MJup and a radius of 1.435RJup, and is
therefore a good target for transmission-spectroscopy observations.
With a density of 0.135g/cm3, it is amongst the lowest-density
planets ever discovered with precisely measured mass and radius.
Description:
Radial velocity measurements of WASP-174 obtained with FEROS. Light
curves of WASP-174 from the HATSouth survey;
light curves of four transit events of the extrasolar planet HATS-13b
and two transit events of the extrasolar planet HATS-14b. Three of the
datasets were obtained using the PEST 30-cm telescope (filter: R), one
with the CTIO 0.9-m telescope (filter: Sloan z) at the Observatory of
Cerro Tololo (Chile), and eight with the MPG 2.2-m telescope (filter:
Sloan g,r,i,z) at the ESO Observatory in La Silla (Chile).
Objects:
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RA (2000) DE Designation(s)
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13 04 10.56 -41 23 05.4 WASP-174 = 2MASS J13031055-4123053
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hs.dat 38 9688 Photom. of WASP-174 from the HATSouth survey
tess.dat 43 975 Photom. of WASP-174 from TESS
grond-g.dat 40 177 Photom. of WASP-174 on 2019/04/09 (GROND g)
grond-r.dat 40 175 Photom. of WASP-174 on 2019/04/09 (GROND r)
grond-i.dat 40 178 Photom. of WASP-174 on 2019/04/09 (GROND i)
grond-z.dat 40 175 Photom. of WASP-174 on 2019/04/09 (GROND z)
grond-j.dat 39 741 Photom. of WASP-174 on 2019/04/09 (GROND J)
grond-h.dat 39 741 Photom. of WASP-174 on 2019/04/09 (GROND H)
grond-k.dat 39 741 Photom. of WASP-174 on 2019/04/09 (GROND K)
lco-g.dat 38 15 Photom. of WASP-174 on 2015/03/24 (LCO 1m g)
lco-i.dat 38 112 Photom. of WASP-174 on 2016/04/16 (LCO 1m i)
pest-r.dat 38 198 Photom. of WASP-174 on 2015/03/07 (PEST 30cm R)
aat-ks.dat 38 1758 Photom. of WASP-174 on 2015/03/07 (AAT Ks)
rv.dat 55 16 RV measurements of WASP-174 (FEROS)
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Byte-by-byte Description of file: [htglpa]*.dat
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Bytes Format Units Label Explanations
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1- 16 F16.10 d BJD Barycentric JD (TDB) for the midpoint of
observation (BJD-2400000)
18- 30 F13.10 mag mag Differential magnitude of the target
32- 43 F12.10 mag e_mag Measurement error of the magnitude
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Byte-by-byte Description of file: rv.dat
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Bytes Format Units Label Explanations
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1- 13 F13.5 d BJD Barycentric JD for the midpoint of
observation ((TDB)
15- 20 F6.2 m/s RV Radial Velocity (RV) of the target
22- 26 F5.2 m/s e_RV Measurement error of RV
28- 34 F7.2 m/s BS ?=- Bisector span (BS)
36- 40 F5.2 m/s e_BS ?=- Measurement error of BS
42- 49 F8.6 --- Phase Phase
51- 57 A7 --- Inst Instrument (FEROS)
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Acknowledgements:
Luigi Mancini, mancini(at)roma2.infnf.it,
University of Rome "Tor Vergata", Italy
(End) Luigi Mancini [Rome Univ., Italy], Patricia Vannier [CDS] 11-Dec-2019