Three short-period Earth-sized planets around M dwarfs discovered by TESS: TOI-5720 b, TOI-6008 b, and TOI-6086 b

Barkaoui, K.; Schwarz, R. P.; Narita, N.; Mistry, P.; Magliano, C.; Hirano, T.; Maity, M.; Burgasser, A. J.; Rackham, B. V.; Murgas, F.; Pozuelos, F. J.; Stassun, K. G.; Everett, M. E.; Ciardi, D. R.; Lamman, C.; Pass, E. K.; Bieryla, A.; Aganze, C.; Esparza-Borges, E.; Collins, K. A.; Covone, G.; de Leon, J.; Dévora-Pajares, M.; de Wit, J.; Fukuda, Izuru; Fukui, A.; Gerasimov, R.; Gillon, M.; Hayashi, Y.; Howell, S. B.; Ikoma, M.; Ikuta, K.; Jenkins, J. M.; Karpoor, P. R.; Kawai, Y.; Kimura, T.; Kotani, T.; Latham, D. W.; Mori, M.; Pallé, E.; Parviainen, H.; Patel, Y. G.; Ricker, G.; Relles, H. M.; Shporer, A.; Seager, S.; Softich, E.; Srdoc, G.; Tamura, M.; Theissen, C. A.; Twicken, J. D.; Vanderspek, R.; Watanabe, N.; Watkins, C. N.; Winn, J. N.; Wohler, B.
Referencia bibliográfica

Astronomy and Astrophysics

Fecha de publicación:
7
2024
Número de autores
56
Número de autores del IAC
7
Número de citas
0
Número de citas referidas
0
Descripción
One of the main goals of the NASA Transiting Exoplanet Survey Satellite (TESS) mission is the discovery of Earth-like planets around nearby M-dwarf stars. We present the discovery and validation of three new short-period Earth-sized planets orbiting nearby M dwarfs: TOI-5720 b, TOI-6008 b, and TOI-6086 b. We combined TESS data, ground-based multicolor light curves, ground-based optical and near-infrared spectroscopy, and Subaru/IRD radial velocity data to validate the planetary candidates and constrain the physical parameters of the systems. In addition, we used archival images, high-resolution imaging, and statistical validation techniques to support the planetary validation. TOI-5720 b is an Earth-sized planet with a radius of Rp = 1.09 ± 0.07 R⊕. It orbits a nearby (36 pc) M 2.5 host with an orbital period of P = 1.4344555 ± 0.0000036 days. It has an equilibrium temperature of Teq = 708 ± 19 K (assuming a null albedo) and an incident flux of Sp = 41.7 ± 4.5 S⊕. TOI-6008 b is a short-period planet of P = 0.8574347 ± 0.0000424 day. It has a radius of Rp = 1.03 ± 0.05 R⊕, an equilibrium temperature of Teq = 707 ± 19 K, and an incident flux of Sp = 41.5 ± 4.5 S⊕. The host star (TOI-6008) is a nearby (23 pc) M 5 with an effective temperature of Teff = 3075 ± 75 K. Based on the radial velocity measurements collected with Subaru/IRD, we set a 3σ upper limit of Mp < 4 M⊕, thus ruling out a star or brown dwarf as the transiting companion. TOI-6086 b orbits its nearby (32 pc) M 3 host star (Teff = 3200 ± 75 K) every 1.3888725 ± 0.0000827 days and has a radius of Rp = 1.18 ± 0.07 R⊕, an equilibrium temperature of Teq = 634 ± 16 K, and an incident flux of Sp = 26.8 ± 2.7 S⊕. Additional high-precision radial velocity measurements are needed to derive the planetary masses and bulk densities and to search for additional planets in the systems. Moreover, short-period Earth-sized planets orbiting around nearby M dwarfs are suitable targets for an atmospheric characterization with the James Webb Space Telescope through transmission and emission spectroscopy and phase-curve photometry.