Revisiting the warm sub-Saturn TOI-1710b. The impact of stellar activity on the mass measurement

April 2024 • 2024A&A...684A..96O

Authors • Orell-Miquel, J. • Carleo, I. • Murgas, F. • Nowak, G. • Pallé, E. • Luque, R. • Masseron, T. • Sanz-Forcada, J. • Dragomir, D. • Dalba, P. A. • Tronsgaard, R. • Wittrock, J. • Kim, K. • Stibbards, C. • Collins, K. I. • Plavchan, P. • Howell, S. B. • Furlan, E. • Buchhave, L. A. • Gnilka, C. L. • Gupta, A. F. • Henning, Th. • Lester, K. V. • Rodriguez, J. E. • Scott, N. J. • Osborn, H. P. • Villanueva, S. • Seager, S. • Winn, J. N. • Jenkins, J. M. • Vanderspek, R. • Latham, D. W. • Rowden, P. • Watanabe, D. • Torres, G. • Burke, C. J. • Daylan, T. • Barclay, T. • Twicken, J. D. • Ricker, G. R.

Abstract • The Transiting Exoplanet Survey Satellite (TESS) provides a continuous suite of new planet candidates that need confirmation and precise mass determination from ground-based observatories. This is the case for the G-type star TOI-1710, which is known to host a transiting sub-Saturn planet (M_p = 28.3 ± 4.7 M_⊕) in a long-period orbit (P = 24.28 days). Here we combine archival SOPHIE and new and archival HARPS-N radial velocity data with newly available TESS data to refine the planetary parameters of the system and derive a new mass measurement for the transiting planet, taking into account the impact of the stellar activity on the mass measurement. We report for TOI-1710b a radius of R_p = 5.15 ± 0.12 R_⊕, a mass of M_p = 18.4 ± 4.5 M_⊕, and a mean bulk density of ρ_p = 0.73 ± 0.18 g cm⁻³, which are consistent at 1.2σ, 1.5σ, and 0.7σ, respectively, with previous measurements. Although there is not a significant difference in the final mass measurement, we needed to add a Gaussian process component to successfully fit the radial velocity dataset. This work illustrates that adding more measurements does not necessarily imply a better mass determination in terms of precision, even though they contribute to increasing our full understanding of the system. Furthermore, TOI-1710b joins an intriguing class of planets with radii in the range 4-8 R_⊕ that have no counterparts in the Solar System. A large gaseous envelope and a bright host star make TOI-1710b a very suitable candidate for follow-up atmospheric characterization.

Links

• PREPRINT http://arxiv.org/abs/2401.13574
• POSTSCRIPT https://www.aanda.org/10.1051/0004-6361/202348131/postscript
• ELECTR https://doi.org/10.1051%2F0004-6361%2F202348131
• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2024A%26A...684A..96O
• PDF https://www.aanda.org/10.1051/0004-6361/202348131/pdf
• DATA https://archive.gemini.edu/searchform/publication=2024A&A...684A..96O
• DATA https://irsa.ipac.caltech.edu/bibdata/2024/O/2024A&A...684A..96O.html