2023/10/13 by Tyler R. Fairnington, Emma Nabbie, Fairnington, Tyler R. +68 · 1 citation
Engineering · Physics and Astronomy · #Astronomical Observations and Instrumentation #Astronomy and Astrophysical Research #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.2310.08890
openalex publication_date 2023/10/13 · openalex created_date 2023/10/17 · openalex updated_date 2026/07/28
We present the confirmation of a hot super-Neptune with an exterior Neptune companion orbiting a bright (V = 10.1 mag) F-dwarf identified by the Transiting Exoplanet Survey Satellite (TESS). The two planets, observed in sectors 45, 46 and 48 of the TESS extended mission, are 4.74+0.16-0.14 R⊕ and 3.86+0.17-0.16 R⊕ with 5.4588385+0.0000070-0.0000072 d and 17.8999+0.0018-0.0013 d orbital periods, respectively. We also obtained precise space based photometric follow-up of the system with ESAs CHaracterising ExOplanets Satellite (CHEOPS) to constrain the radius and ephemeris of TOI-5126 b. TOI 5126 b is located in the "hot Neptune Desert" and is an ideal candidate for follow-up transmission spectroscopy due to its high predicted equilibrium temperature (Teq = 1442+46-40 K) implying a cloud-free atmosphere. TOI-5126 c is a warm Neptune (Teq= 971+31-27 K) also suitable for follow-up. Tentative transit timing variations (TTVs) have also been identified in analysis, suggesting the presence of at least one additional planet, however this signal may be caused by spot-crossing events, necessitating further precise photometric follow-up to confirm these signals.