TOI-2374 b and TOI-3071 b: two metal-rich sub-Saturns well within the Neptunian desert

• Type: Article in International Scientific Journal
• Date: 2024

Authors

Lewis, H (Author) Other; Lillo Box, J (Author) Other; Lund, MB (Author) Other; Nielsen, LD (Author) Other; Osborn, A (Author) Other; Osip, D (Author) Other; Paegert, M (Author) Other; Radford, DJ (Author) Other; N.C. Santos (Author) FCUP; Seager, S (Author) Other; Shectman, SA (Author) Other; Srdoc, G (Author) Other; Strom, PA (Author) Other; Tan, TG (Author) Other; Teske, JK (Author) Other; Vezie, M (Author) Other; Watanabe, D (Author) Other; Watkins, CN (Author) Other; Wheatley, PJ (Author) Other; Winn, JN (Author) Other; Wohler, B (Author) Other; Ziegler, C (Author) Other; Hacker, A (Author) Other; Díaz, RF (Author) Other; Armstrong, DJ (Author) Other; Fernández, JF (Author) Other; Müller, S (Author) Other; Delgado Mena, E (Author) FCUP; Sousa, SG (Author) FCUP; Adibekyan, V (Author) Other; Stassun, KG (Author) Other; Collins, KA (Author) Other; Yee, SW (Author) Other; Bayliss, D (Author) Other; Bieryla, A (Author) Other; Bouchy, F (Author) Other; Butler, RP (Author) Other; Crane, JD (Author) Other; Dumusque, X (Author) Other; Hartman, JD (Author) Other; Helled, R (Author) Other; Jenkins, J (Author) Other; Keniger, MAF (Author) Other

Journal

Title: Monthly Notices of the Royal Astronomical Society

Vol. 532

Pages: 1612-1634

ISSN: 0035-8711

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 0 Citations

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Other information

Authenticus ID: P-010-YP4

DOI: 10.1093/mnras/stae1420

Abstract (EN): We report the discovery of two transiting planets detected by the Transiting Exoplanet Survey Satellite (TESS), TOI-2374 b and TOI-3071 b, orbiting a K5V and an F8V star, respectively, with periods of 4.31 and 1.27 d, respectively. We confirm and characterize these two planets with a variety of ground-based and follow-up observations, including photometry, precise radial velocity monitoring and high-resolution imaging. The planetary and orbital parameters were derived from a joint analysis of the radial velocities and photometric data. We found that the two planets have masses of (57 +/- 4) M-circle plus or (0.18 +/- 0.01) M-J, and (68 +/- 4) M-circle plus or (0.21 +/- 0.01) M-J, respectively, and they have radii of (6.8 +/- 0.3) R-circle plus or (0.61 +/- 0.03) R-J and (7.2 +/- 0.5) R-circle plus or (0.64 +/- 0.05) R-J, respectively. These parameters correspond to sub-Saturns within the Neptunian desert, both planets being hot and highly irradiated, with T-eq approximate to 745 K and T-eq approximate to 1812 K, respectively, assuming a Bond albedo of 0.5. TOI-3071 b has the hottest equilibrium temperature of all known planets with masses between 10 and 300 M-circle plus and radii less than 1.5 R-J. By applying gas giant evolution models we found that both planets, especially TOI-3071 b, are very metal-rich. This challenges standard formation models which generally predict lower heavy-element masses for planets with similar characteristics. We studied the evolution of the planets' atmospheres under photoevaporation and concluded that both are stable against evaporation due to their large masses and likely high metallicities in their gaseous envelopes.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 23