TOI-1801 b: A temperate mini-Neptune around a young M0.5 dwarf

Mallorquín, M.; Goffo, E.; Pallé, E.; Lodieu, N.; Béjar, V.J.S.; Isaacson, H.; Zapatero, Osorio, M.R.; Dreizler, S.; Stock, S.; Luque, R.; Murgas, F.; Peña, L.; Sanz-Forcada, J.; Morello, G.; Ciardi, D.R.; Furlan, E.; Collins, K.A.; Herrero, E.; Vanaverbeke, S.; Plavchan, P.; Narita, N.; Schweitzer, A.; Pérez-Torres, M.; Quirrenbach, A.; Kemmer, J.; Hatzes, A.P.; Howard, A.; Schlecker, M.; Reffert, S.; Nagel, E.; Morales, J.C.; Orell-Miquel, J.; Duque-Arribas, C.; Carleo, I.; Cifuentes, C.; Nowak, G.; Ribas, I.; Reiners, A.; Amado, P.J.; Caballero, J.A.; Henning, Th.; Pinter, V.; Akana, Murphy, J.M.; Beard, C.; Blunt, S.; Brinkman, C.L.; Cale, B.; Chontos, A.; Collins, K.I.; Crossfield, I.J.M.; Dai, F.; Dalba, P.A.; Dufoer, S.; El, Mufti, M.; Espinoza, N.; Fetherolf, T.; Fukui, A.; Giacalone, S.; Gnilka, C.; Gonzales, E.; Grunblatt, S.K.; Howell, S.; Huber, D.; Kane, S.R.; de León, J.; Lubin, J.; MacDougall, M.G.; Massey, B.; Montes, D.; Mori, M.; Parviainen, H.; Passegger, V.M.; Polanski, A.S.; Robertson, P.; Schwarz, R.P.; Srdoc, G.; Tabernero, H.M.; Tanner, A.; Turtelboom, E.; Van Zandt, J.; Weiss, L.; Zechmeister, M.

Name:

aa47346-23.pdf

Size:

8.982Mb

Format:

PDF

Description:

Final Published Version

Download

Author

Mallorquín, M.
Goffo, E.
Pallé, E.
Lodieu, N.
Béjar, V.J.S.
Isaacson, H.
Zapatero, Osorio, M.R.
Dreizler, S.
Stock, S.
Luque, R.

Show all

Affiliation

Steward Observatory, Department of Astronomy, The University of Arizona

Issue Date

2023-12-13

Citation

A&A, 680, A76 (2023)

Journal

Astronomy and Astrophysics

Rights

Collection Information

This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.

Abstract

We report the discovery, mass, and radius determination of TOI-1801 b, a temperate mini-Neptune around a young M dwarf. TOI- 1801 b was observed in TESS sectors 22 and 49, and the alert that this was a TESS planet candidate with a period of 21.3 days went out in April 2020. However, ground-based follow-up observations, including seeing-limited photometry in and outside transit together with precise radial velocity (RV) measurements with CARMENES and HIRES revealed that the true period of the planet is 10.6 days. These observations also allowed us to retrieve a mass of 5.74 ± 1.46 M⊕, which together with a radius of 2.08 ± 0.12 R⊕, means that TOI-1801 b is most probably composed of water and rock, with an upper limit of 2% by mass of H2 in its atmosphere. The stellar rotation period of 16 days is readily detectable in our RV time series and in the ground-based photometry. We derived a likely age of 600-800 Myr for the parent star TOI-1801, which means that TOI-1801 b is the least massive young mini-Neptune with precise mass and radius determinations. Our results suggest that if TOI-1801 b had a larger atmosphere in the past, it must have been removed by some evolutionary mechanism on timescales shorter than 1 Gyr. © The Authors 2023.

Note

Open access journal

ISSN

0004-6361

DOI

10.1051/0004-6361/202347346

Version

Final Published Version

Collections

UA Faculty Publications

© The Authors 2023. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0).

Except where otherwise noted, this item's license is described as © The Authors 2023. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0).