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arXiv · 2511.20119

Precise mass and radius determination for two new and one known Neptune-sized planets around G Dwarf hosts

Ilaria Carleo·Grzegorz Nowak·Felipe Murgas·Enric Pallé·Gaia Lacedelli·Thomas Masseron·Emily W. Wong·Amadeo Castro-González·Dawid Jankowski·Patrick Eggenberger·James S. Jenkins·Krzysztof Goździewski·Vincent Bourrier·Douglas R. Alves·José I. Vines·Keivan G. Stassun·Matteo Brogi·Sergio Messina·Catherine A. Clark·Karen A. Collins·Hans J. Deeg·Elise Furlan·Davide Gandolfi·Samuel Geraldía González·Coel Hellier·Artie P. Hatzes·Steve B. Howell·Judith Korth·Emil Knudstrup·Jorge Lillo-Box·John H. Livingston·Jaume Orell-Miquel·Carina Persson·Seth Redfield·Boris Safonov·David Baker·Rafael Delfin Barrena Delgado·Allyson Bieryla·Andrew Boyle·Pau Bosch-Cabot·Núria Casasayas Barris·Stavros Chairetas·David R. Ciardi·Akihiko Fukui·Pere Guerra·Kiyoe Kawauchi·Florence Libotte·Michael B. Lund·Rafael Luque·Eduardo Lorenzo Martín Guerrero de Escalante·Bob Massey·Edward J. Michaels·Giuseppe Morello·Norio Narita·Hannu Parvianien·Richard P. Schwarz·Avi Shporer·Monika Stangret·Cristilyn N. Watkins
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Abstract

As part of the KESPRINT collaboration, we present the discovery and characterization of three exoplanets in the sub-Neptune to super-Neptune regime, spanning key regions of the exo-Neptunian landscape. TOI-1472c and TOI-1648b are newly discovered sub-Neptunes, while TOI-1472b is a previously known super-Neptune for which we provide an improved mass measurement. These planets have orbital periods of 6--15 days and radii of 2.5--4.1 R$_\oplus$, probing regions where planet formation and atmospheric evolution remain poorly understood. We combine TESS transit photometry with ground-based radial velocities to determine precise masses, radii, and orbital properties. TOI-1472b has a mass of $18.0^{+0.84}_{-0.85}$ M$_\oplus$ and a radius of $4.06 \pm 0.10$ R$_\oplus$, TOI-1472c has a mass of $21.1^{+0.96}_{-0.99}$ M$_\oplus$ and a radius of $3.33 \pm 0.08$ R$_\oplus$, and TOI-1648b has a mass of $7.4^{+1.1}_{-1.3}$ M$_\oplus$ and a radius of $2.54^{+0.14}_{-0.12}$ R$_\oplus$. The planets exhibit a range of eccentricities (0.041--0.178), indicating diverse evolutionary histories. TOI-1648b, with a high Transmission Spectroscopy Metric (TSM $\sim$59), is a promising target for atmospheric characterization. Together, these three planets provide precise constraints on the structure, composition, and dynamical evolution of small to intermediate-sized exoplanets, enriching our understanding of the exo-Neptunian landscape.

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Ilaria Carleo, Grzegorz Nowak, Felipe Murgas, Enric Pallé, Gaia Lacedelli, Thomas Masseron, Emily W. Wong, Amadeo Castro-González, Dawid Jankowski, Patrick Eggenberger, James S. Jenkins, Krzysztof Goździewski, Vincent Bourrier, Douglas R. Alves, José I. Vines, Keivan G. Stassun, Matteo Brogi, Sergio Messina, Catherine A. Clark, Karen A. Collins, Hans J. Deeg, Elise Furlan, Davide Gandolfi, Samuel Geraldía González, Coel Hellier, Artie P. Hatzes, Steve B. Howell, Judith Korth, Emil Knudstrup, Jorge Lillo-Box, John H. Livingston, Jaume Orell-Miquel, Carina Persson, Seth Redfield, Boris Safonov, David Baker, Rafael Delfin Barrena Delgado, Allyson Bieryla, Andrew Boyle, Pau Bosch-Cabot, Núria Casasayas Barris, Stavros Chairetas, David R. Ciardi, Akihiko Fukui, Pere Guerra, Kiyoe Kawauchi, Florence Libotte, Michael B. Lund, Rafael Luque, Eduardo Lorenzo Martín Guerrero de Escalante, Bob Massey, Edward J. Michaels, Giuseppe Morello, Norio Narita, Hannu Parvianien, Richard P. Schwarz, Avi Shporer, Monika Stangret, Cristilyn N. Watkins. 2025-11-25. Precise mass and radius determination for two new and one known Neptune-sized planets around G Dwarf hosts. https://arxiv.org/abs/2511.20119

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