Confirmation and characterisation of three giant planets detected by TESS from the FIES/NOT and Tull/McDonald spectrographs

¹ Nordic Optical Telescope, Rambla José Ana Fernandez Pérez 7, ES-38711 Breña Baja, Spain
² Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
e-mail: emil@phys.au.dk
³ Dipartimento di Fisica, Università degli Studi di Torino, via Pietro Giuria 1, 10125 Torino, Italy
⁴ McDonald Observatory and Center for Planetary Systems Habitability, The University of Texas, Austin Texas, USA
⁵ DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 328, 2800 Kgs. Lyngby, Denmark
⁶ Center for Astrophysics | Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA
⁷ Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235, USA
⁸ Instituto de Astrofísica de Canarias (IAC), 38205 La Laguna, Tenerife, Spain
⁹ Dept. Astrofísica, Universidad de La Laguna (ULL), 38206 La Laguna, Tenerife, Spain
¹⁰ Astrobiology Research Unit, Université de Liège, Allée du 6 Août 19C, 4000 Liège, Belgium
¹¹ Department of Earth, Atmospheric and Planetary Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
¹² Sternberg Astronomical Institute, Lomonosov Moscow State University, 13 Universitetski prospekt, 119992 Moscow, Russia
¹³ SETI Institute, Mountain View, CA 94043, USA
¹⁴ NASA Ames Research Center, Moffett Field, CA 94035, USA
¹⁵ Department of Astronomy, California Institute of Technology, Pasadena, CA 91125, USA
¹⁶ Department of Astronomy, University of California Berkeley, Berkeley CA 94720, USA
¹⁷ Centre for Astrophysics, University of Southern Queensland, Toowoomba, QLD, Australia
¹⁸ Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
¹⁹ George Mason University, 4400 University Drive, Fairfax, VA 22030, USA
²⁰ American Association of Variable Star Observers, 49 Bay State Road, Cambridge, MA 02138, USA
²¹ Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
²² Department of Astronomy and Tsinghua Centre for Astrophysics, Tsinghua University, Beijing 100084, PR China
²³ Department of Physics and Astronomy, University of Louisville, Louisville, KY 40292, USA
²⁴ Villa ’39 Observatory, Landers, CA 92285, USA
²⁵ Department of Physical Sciences, Kutztown University, Kutztown, PA 19530, USA
²⁶ Department of Aeronautics and Astronautics, MIT, 77 Massachusetts Ave., Cambridge, MA 02139, USA
²⁷ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
²⁸ Patashnick Voorheesville Observatory, Voorheesville, NY 12186, USA
²⁹ Kotizarovci Observatory, Sarsoni 90, 51216 Viskovo, Croatia
³⁰ Planetary Discoveries, Fredericksburg, VA 22405, USA

Received: 28 March 2022
Accepted: 11 July 2022

Abstract

We report the confirmation and characterisation of TOI-1820 b, TOI-2025 b, and TOI-2158 b, three Jupiter-sized planets on short-period orbits around G-type stars detected by TESS. Through our ground-based efforts using the FIES and Tull spectrographs, we have confirmed these planets and characterised their orbits, and find periods of around 4.9 d, 8.9 d, and 8.6 d for TOI-1820 b, TOI-2025 b, and TOI-2158 b, respectively. The sizes of the planets range from 0.96 to 1.14 Jupiter radii, and their masses are in the range from 0.8 to 4.4 Jupiter masses. For two of the systems, namely TOI-2025 and TOI-2158, we see a long-term trend in the radial velocities, indicating the presence of an outer companion in each of the two systems. For TOI-2025 we furthermore find the star to be well aligned with the orbit, with a projected obliquity of 9₋₃₁⁺³³°. As these planets are all found in relatively bright systems (V ~ 10.9–11.6 mag), they are well suited for further studies, which could help shed light on the formation and migration of hot and warm Jupiters.