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Title: The TESS-Keck Survey. XXII. A Sub-Neptune Orbiting TOI-1437
Abstract Exoplanet discoveries have revealed a dramatic diversity of planet sizes across a vast array of orbital architectures. Sub-Neptunes are of particular interest; due to their absence in our own solar system, we rely on demographics of exoplanets to better understand their bulk composition and formation scenarios. Here, we present the discovery and characterization of TOI-1437 b, a sub-Neptune with a 18.84 day orbit around a near-solar analog (M⋆= 1.10 ± 0.10M☉,R⋆=1.17 ± 0.12R☉). The planet was detected using photometric data from the Transiting Exoplanet Survey Satellite (TESS) mission and radial velocity (RV) follow-up observations were carried out as a part of the TESS-Keck Survey using both the HIRES instrument at Keck Observatory and the Levy Spectrograph on the Automated Planet Finder telescope. A combined analysis of these data reveal a planet radius ofRp= 2.24 ± 0.23R⊕and a mass measurement ofMp= 9.6 ± 3.9M⊕). TOI-1437 b is one of few (∼50) known transiting sub-Neptunes orbiting a solar-mass star that has a RV mass measurement. As the formation pathway of these worlds remains an unanswered question, the precise mass characterization of TOI-1437 b may provide further insight into this class of planet.  more » « less
Award ID(s):
2401863
PAR ID:
10538142
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Volume:
168
Issue:
3
ISSN:
0004-6256
Format(s):
Medium: X Size: Article No. 135
Size(s):
Article No. 135
Sponsoring Org:
National Science Foundation
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