학술논문
WASP-193b: An extremely low-density super-Neptune
Document Type
Working Paper
Author
Barkaoui, Khalid; Pozuelos, Francisco J.; Hellier, Coel; Smalley, Barry; Nielsen, Louise D.; Dorn, Caroline; Niraula, Prajwal; Gillon, Michaël; de Wit, Julien; Helled, Ravit; Müller, Simon; Jehin, Emmanuel; Demory, Brice-Olivier; Van Grootel, V.; Soubkiou, Abderahmane; Ghachoui, Mourad; Anderson, David. R.; Benkhaldoun, Zouhair; Bouchy, Francois; Burdanov, Artem; Delrez, Laetitia; Ducrot, Elsa; Garcia, Lionel; Jabiri, Abdelhadi; Lendl, Monika; Maxted, Pierre F. L.; Murray, Catriona A.; Pedersen, Peter Pihlmann; Queloz, Didier; Sebastian, Daniel; Turner, Oliver; Udry, Stephane; Timmermans, Mathilde; Triaud, Amaury H. M. J.; West, Richard G.
Source
Subject
Language
Abstract
Gas giants transiting bright nearby stars are stepping stones for our understanding of planetary system formation and evolution mechanisms. This paper presents a particularly interesting new specimen of this kind of exoplanet discovered by the WASP-South transit survey, WASP-193b. This planet completes an orbit around its Vmag = 12.2 F9 main-sequence host star every 6.25 d. Our analyses found that WASP-193b has a mass of Mp = 0.139 +/- 0.029 M_Jup and a radius of Rp = 1.464 +/- 0.058 R_ Jup, translating into an extremely low density of rhop = 0.059 +\- 0.014 g/cm^3. The planet was confirmed photometrically by the 0.6-m TRAPPIST-South, the 1.0-m SPECULOOS-South telescopes, and the TESS mission, and spectroscopically by the ESO-3.6-m/HARPS and Euler-1.2-m/CORALIE spectrographs. The combination of its large transit depth (dF~1.4 %), its extremely-low density, its high-equilibrium temperature (Teq = 1254 +/- 31 K), and the infrared brightness of its host star (magnitude Kmag=10.7) makes WASP-193b an exquisite target for characterization by transmission spectroscopy (transmission spectroscopy metric: TSM ~ 600). One single JWST transit observation would yield detailed insights into its atmospheric properties and planetary mass, within ~0.1 dex and ~1% (vs ~20% currently with radial velocity data) respectively.
Comment: Accepted for publication
Comment: Accepted for publication