A gem system with a lava world and a habitable zone sub-Neptune orbiting TOI–1752
/ Authors
A. Peláez-Torres, F. Pozuelos, G. Morello, M. Dévora-Pajares, K. Barkaoui, L. Gkouvelis, E. Pallé, K. Collins, B. Rackham, S. Geraldía-González
and 40 more authors
M. Centenera-Merino, R. Varas, E. Esparza-Borges, Z. Parlapani, J. Flores, J. Aceituno, P. J. Amado, A. Burdanov, Y. Calatayud-Borras, D. Ciardi, B. Demory, T. Gan, S. Giacalone, M. Gillon, Y. G. M. Chew, K. Kawauchi, A. Khandelwal, J. Korth, M. Lendl, J. P. de Leon, J. Livingston, N. Morales, F. Murgas, N. Narita, J. L. Ortiz, H. Parviainen, M. Marcano, I. Plauchu-Frayn, D. Queloz, D. Rapetti, J. Saito, A. Sánchez-López, A. Savel, R. Schwarz, U. Schroffenegger, M. Serra-Ricart, C. Stockdale, A. Triaud, J. de Wit, F. Z. Lang
/ Abstract
The Transiting Exoplanet Survey Satellite (TESS) has delivered a large number of transiting planet candidates around nearby stars by identifying periodic decreases in stellar brightness. Establishing the planetary nature of these signals and determining their fundamental properties is a necessary step toward detailed studies of their internal structure, atmospheres, and formation pathways. In this work, we investigate the planetary nature of the TOI–1752 system (M1 V, 103.02 ± 0.34 pc), which hosts two TESS candidates: TOI–1752 b, a short-period object consistent with a lava-world scenario, and TOI–1752 c, a sub-Neptune-size planet candidate located in the optimistic habitable zone. We obtained ground-based multi-color photometric follow-up observations of TOI–1752, which we combined with TESS photometry to assess the nature of both signals. We performed a formal statistical validation using the TRICERATOPS framework, while independently vetting the candidates with the neural-network-based classifier WATSON-Net, which provides a machine-learning assessment of their planetary likelihood based on light-curve morphology, centroid diagnostics, and auxiliary vetting features. We validate TOI–1752 b as a bona fide planet with a radius of 1.69 ± 0.07R⊕ and an orbital period of $0.935186^{+0.000001}_{-0.000002}$ days, and TOI–1752 c with a radius of $2.29^{+0.13}_{-0.14} R_{\oplus }$ and an orbital period of 32.7144 ± 0.0004 days. The combined analysis confirms TOI–1752 as a new planetary system, places TOI–1752 c within the optimistic habitable zone of its host star, and identifies TOI–1752 b as a promising target for atmospheric characterization, with an estimated emission spectroscopy metric (ESM) of up to ~8.
Journal: Monthly Notices of the Royal Astronomical Society