J/MNRAS/450/1760 Transiting planet WASP-6b (Tregloan-Reed+, 2015)
Transits and starspots in the WASP-6 planetary system.
Tregloan-Reed J., Southworth J., Burgdorf M., Calchi Novati S., Dominik M.,
Finet F., Jorgensen U.G., Maier G., Mancini L., Prof S., Ricci D.,
Snodgrass C., Bozza V., Browne P., Dodds P., Gerner T., Harpsoe K.,
Hinse T.C., Hundertmark M., Kains N., Kerins E., Liebig C., Penny M.T.,
Rahvar S., Sahu K., Scarpetta G., Schafer S., Schonebeck F., Skottfelt J.,
Surdej J.
<Mon. Not. R. Astron. Soc., 450, 1760-1769 (2015)>
=2015MNRAS.450.1760T 2015MNRAS.450.1760T (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Photometry
Keywords: techniques: photometric - stars: fundamental parameters -
stars: individual: WASP-6 - planetary systems - starspots
Abstract:
We present updates to prism, a photometric transit-starspot model, and
gemc, a hybrid optimization code combining MCMC and a genetic
algorithm. We then present high-precision photometry of four transits
in the WASP-6 planetary system, two of which contain a starspot
anomaly. All four transits were modelled using prism and gemc, and the
physical properties of the system calculated. We find the mass and
radius of the host star to be 0.836±0.063M☉ and
0.864±0.024R☉, respectively. For the planet, we find a mass of
0.485±0.027MJup, a radius of 1.230±0.035RJup and a
density of 0.244±0.014ρJup. These values are consistent with
those found in the literature. In the likely hypothesis that the two
spot anomalies are caused by the same starspot or starspot complex, we
measure the stars rotation period and velocity to be 23.80±0.15d
and 1.78±0.20km/s, respectively, at a colatitude of 75.8°. We
find that the sky-projected angle between the stellar spin axis and
the planetary orbital axis is λ=7.2°±3.7°,
indicating axial alignment. Our results are consistent with and more
precise than published spectroscopic measurements of the
Rossiter-McLaughlin effect. These results suggest that WASP-6 b formed
at a much greater distance from its host star and suffered orbital
decay through tidal interactions with the protoplanetary disc.
Description:
Four light curves of transits of the extrasolar planetary system
WASP-6 are presented. They were obtained using the Danish 1.54m
telescope at ESO La Silla, Chile, in the Bessell R passband. The
errorbars for each transit have been scaled so the best-fitting model
(obtained using the JKTEBOP code and without accounting for the
presence of starspots) has a reduced chi-squared value of 1.0.
Objects:
--------------------------------------------------------------
RA (2000) DE Designation(s)
--------------------------------------------------------------
23 12 37.74 -22 40 26.3 WASP-6 = 1SWASP J231237.75-224026.1
--------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
wasp6.dat 35 582 Photometry of WASP-6
--------------------------------------------------------------------------------
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/428/3671 : Transiting planet WASP-19b (Tregloan-Reed+, 2013)
J/MNRAS/431/966 : Transiting planet WASP-50b (Tregloan-Reed+, 2013)
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)
Byte-by-byte Description of file: wasp6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 F14.6 d BJD Barycentric JD for the midpoint of
observation (TDB)
16- 25 F10.7 mag dmag Differential magnitude in the Bessell R filter
27- 35 F9.7 mag e_dmag Measurement error of the differential magnitude
--------------------------------------------------------------------------------
Acknowledgements:
John Southworth, astro.js(at)keele.ac.uk
References:
Southworth et al., Paper I 2009MNRAS.396.1023S 2009MNRAS.396.1023S, Cat. J/MNRAS/396/1023
Southworth et al., Paper II 2009MNRAS.399..287S 2009MNRAS.399..287S, Cat. J/MNRAS/399/287
Southworth et al., Paper III 2010MNRAS.408.1680S 2010MNRAS.408.1680S, Cat. J/MNRAS/408/1680
Southworth et al., Paper IV 2012MNRAS.426.1338S 2012MNRAS.426.1338S, Cat. J/MNRAS/426/1338
Southworth et al., Paper V 2013MNRAS.434.1300S 2013MNRAS.434.1300S, Cat. J/MNRAS/434/1300
Southworth et al., Paper VI 2014MNRAS.444..776S 2014MNRAS.444..776S, Cat. J/MNRAS/444/776
Southworth et al., Paper VII 2015MNRAS.447..711S 2015MNRAS.447..711S, Cat. J/MNRAS/447/711
(End) John Southworth [Keele Univ., UK], Patricia Vannier [CDS] 24-May-2018