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This content will become publicly available on October 10, 2025

Title: 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 ± 0.042MJ, a radius of 0.744 ± 0.017RJ, and an orbital period of 3.4717 days. It transits a mid-M-dwarf star with a mass of 0.442 ± 0.025Mand a radius of 0.4250 ± 0.0091R. 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 ± 0.010M. The planet TIC 46432937 b is a warm super-Jupiter with a mass of 3.20 ± 0.11MJand radius of 1.188 ± 0.030RJ. The planet’s orbital period isP= 1.4404 days, and it undergoes grazing transits of its early M-dwarf host star, which has a mass of 0.563 ± 0.029Mand a radius of 0.5299 ± 0.0091R. 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 3.0MJ, equilibrium temperature below 1000 K).  more » « less
Award ID(s):
1945633
PAR ID:
10582943
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
The Astronomical Journal
Volume:
168
Issue:
5
ISSN:
0004-6256
Page Range / eLocation ID:
202
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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