TOI 762 A b and TIC 46432937 b: Two Giant Planets Transiting M-dwarf Stars
Abstract
We present the discovery of TOI 762 A b and TIC 46432937 b, two giant planets transiting M-dwarf stars. Transits of both systems were first detected from observations by the NASA TESS mission, and the transiting objects are confirmed as planets through high-precision radial velocity observations carried out with Very Large Telescope/ESPRESSO. TOI 762 A b is a warm sub-Saturn with a mass of 0.251 ± 0.042 M J, a radius of 0.744 ± 0.017 R J, and an orbital period of 3.4717 days. It transits a mid-M-dwarf star with a mass of 0.442 ± 0.025 M ☉ and a radius of 0.4250 ± 0.0091 R ☉. The star TOI 762 A has a resolved binary star companion, TOI 762 B, that is separated from TOI 762 A by 3.″2 (∼319 au) and has an estimated mass of 0.227 ± 0.010 M ☉. The planet TIC 46432937 b is a warm super-Jupiter with a mass of 3.20 ± 0.11 M J and radius of 1.188 ± 0.030 R J. The planet's orbital period is P = 1.4404 days, and it undergoes grazing transits of its early M-dwarf host star, which has a mass of 0.563 ± 0.029 M ☉ and a radius of 0.5299 ± 0.0091 R ☉. TIC 46432937 b is one of the highest-mass planets found to date transiting an M-dwarf star. TIC 46432937 b is also a promising target for atmospheric observations, having the highest transmission spectroscopy metric or emission spectroscopy metric value of any known warm super-Jupiter (mass greater than 3.0 M J, equilibrium temperature below 1000 K).
- Publication:
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The Astronomical Journal
- Pub Date:
- November 2024
- DOI:
- arXiv:
- arXiv:2407.07187
- Bibcode:
- 2024AJ....168..202H
- Keywords:
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- Exoplanet systems;
- Exoplanet astronomy;
- Transit photometry;
- Radial velocity;
- Space telescopes;
- M dwarf stars;
- Extrasolar gaseous giant planets;
- 484;
- 486;
- 1709;
- 1332;
- 1547;
- 982;
- 509;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- 29 pages, 7 figures, 8 tables, accepted for publication in AAS Journals