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arXiv · 2405.12448

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 (Mstar = 1.10 +/- 0.10 Msun, Rstar = 1.17 +/- 0.12 Rsun). The planet was detected using photometric data from the Transiting Exoplanet Survey Satellite (TESS) mission and radial velocity follow-up observations were carried out as a part of the TESS-Keck Survey (TKS) using both the HIRES instrument at Keck Observatory and the Levy Spectrograph on the Automated Planet Finder (APF) telescope. A combined analysis of these data reveal a planet radius of Rp = 2.24 +/- 0.23 Rearth and a mass measurement of Mp = 9.6 +/- 3.9 Mearth). TOI-1437 b is one of few (~50) known transiting sub-Neptunes orbiting a solar-mass star that has a radial velocity 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.

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Daria Pidhorodetska, Emily A. Gilbert, Stephen R. Kane, Thomas Barclay, Alex S. Polanski, Michelle L. Hill, Keivan G. Stassun, Steven Giacalone, David R. Ciardi, Andrew W. Boyle, Steve B. Howell, Jorge Lillo-Box, Mason G. MacDougall, Tara Fetherolf, Natalie M. Batalha, Ian J. M. Crossfield, Courtney Dressing, Benjamin Fulton, Andrew W. Howard, Daniel Huber, Howard Isaacson, Erik A. Petigura, Paul Robertson, Lauren M. Weiss, Isabel Angelo, Corey Beard, Aida Behmard, Sarah Blunt, Casey L. Brinkman, Ashley Chontos, Fei Dai, Paul A. Dalba, Rae Holcomb, Jack Lubin, Andrew W. Mayo, Joseph M. Akana Murphy, Malena Rice, Ryan Rubenzahl, Nicholas Scarsdale, Emma V. Turtelboom, Dakotah Tyler, Judah Van Zandt, Edward W. Schwieterman. 2024-05-21. The TESS-Keck Survey. XXII. A sub-Neptune Orbiting TOI-1437. https://arxiv.org/abs/2405.12448

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