TOI-512: Super-Earth transiting a K-type star discovered by TESS and ESPRESSO

Rodrigues, J.; Barros, S. C. C.; Santos, N. C.; Davoult, J.; Attia, M.; Castro-González, A.; Sousa, S. G.; Demangeon, O. D. S.; Hobson, M. J.; Bossini, D.; Ziegler, C.; Faria, J. P.; Adibekyan, V.; Lovis, C.; Lavie, B.; Damasso, M.; Silva, A. M.; Suárez Mascareño, A.; Pepe, F.; Bouchy, F.; Alibert, Y.; González Hernández, J. I.; Sozzetti, A.; Allende Prieto, C.; Cristiani, S.; Palle, E.; D’Odorico, V.; Ehrenreich, D.; Figueira, P.; Stassun, K. G.; Génova Santos, R.; Lo Curto, G.; A. P. Martins, C. J.; Mehner, A.; Micela, G.; Molaro, P.; Nunes, N. J.; Poretti, E.; Rebolo, R.; Udry, S.; Zapatero Osorio, M. R.

doi:10.48620/89148

TOI-512: Super-Earth transiting a K-type star discovered by TESS and ESPRESSO

BORIS DOI

10.48620/89148

Publisher DOI

10.1051/0004-6361/202452887

Description

Context. One of the goals of the ESPRESSO guaranteed time observations (GTOs) at the ESO 8.2 m telescope is to follow up on candidate planets from transit surveys such as the TESS mission. High-precision radial velocities are required to characterize small exoplanets.
Aims. We intend to confirm the existence of a transiting super-Earth around the bright (V=9.74) K0-type star TOI-512 (TIC 119292328) and provide a characterization.
Methods. Combining photometric data from TESS and 37 high-resolution spectroscopic observations from ESPRESSO in a joint Markov chain Monte Carlo analysis, we determined the planetary parameters of TOI-512b and characterized its internal structure.
Results. We find that TOI-512b is a super-Earth, with a radius of 1.54 ± 0.10 R⊕ and mass of 3.57−0.55+0.53 M⊕, on a 7.19−6.1·10−5+7.10−5 day orbit. This corresponds to a bulk density of 5.62−1.28+1.59 g cm−3. Our interior structure analysis presents a small inner core representing 0.13−0.11+0.13 of the solid mass fraction for the planet, surrounded by a mantle with a mass fraction of 0.69−0.22+0.20, and an upper limit of the water layer of 0.16. The gas mass below 10−8.93 indicates a very small amount of gas on the planet. We find no evidence of the second candidate found by the TESS pipeline, TOI-512.02, neither in TESS photometry, nor in the ESPRESSO radial velocities. The low stellar activity makes it an interesting transmission spectroscopy candidate for future-generation instruments.

Date of Publication

2025-03

Publication Type

Article

Subject(s)

500 Science > 530 Physics

Language(s)

en

Contributor(s)

Rodrigues, J.
Barros, S. C. C.
Santos, N. C.
Davoult, J.	NCCR PlanetS, PlanetS A5
	NCCR PlanetS
Attia, M.
Castro-González, A.
Sousa, S. G.
Demangeon, O. D. S.
Hobson, M. J.
Bossini, D.
Ziegler, C.
Faria, J. P.
Adibekyan, V.
Lovis, C.
Lavie, B.
Damasso, M.
Silva, A. M.
Suárez Mascareño, A.
Pepe, F.
Bouchy, F.
Alibert, Y.	Physics Institute, Space Research and Planetary Sciences
	Space Research and Planetology Physics - Planetary Formation
González Hernández, J. I.
Sozzetti, A.
Allende Prieto, C.
Cristiani, S.
Palle, E.
D’Odorico, V.
Ehrenreich, D.
Figueira, P.
Stassun, K. G.
Génova Santos, R.
Lo Curto, G.
A. P. Martins, C. J.
Mehner, A.
Micela, G.
Molaro, P.
Nunes, N. J.
Poretti, E.
Rebolo, R.
Udry, S.
Zapatero Osorio, M. R.