Demographics of close-in TESS exoplanets orbiting FGK main-sequence stars

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Authors: Kaiming Cui, D. J. Armstrong, Andreas Hadjigeorghiou, M. Lafarga, V. Kunovac, Lauren Doyle, Luis Agustín Nieto, R. F. Díaz
Cited by: 3
References: 90

Abstract

ABSTRACT Understanding the demographics of close-in planets is crucial for insights into exoplanet formation and evolution. We present a detailed analysis of occurrence rates for close-in (0.5–16 d) planets with radii between 2 and 20 $\hbox{R}_{\oplus }$ around FGK main-sequence stars. Our study uses a comprehensive sample from four years of TESS Science Processing Operations Center full-frame image data cross-matched with Gaia, analysed through our rigorous detection, vetting, and validation pipeline. Using high-confidence planet candidates, we apply a hierarchical Bayesian model to determine occurrence rates in the two-dimensional orbital period-radius plane. Our results are presented using 10-by-10 bins across the period-radius parameter space, offering unprecedented resolution and statistical precision. We find an overall occurrence rate of $9.4^{+0.7}_{-0.6}\,\rm per\,cent$. When using identical binning, our occurrence rate posteriors distributions align with Kepler’s but have a magnitude smaller uncertainties on average. For hot Jupiters, we estimate the overall occurrence rate of $0.39^{+0.03}_{-0.02}\,\rm per\,cent$. This value is consistent with the previous Kepler FGK-type result within $1\sigma$. We find an overall occurrence rate of Neptunian desert planets of $0.08\pm 0.01~\rm per\,cent$, to our knowledge the first such determination. Additionally, in a volume-limited Gaia subsample within 100 pc in the same parameter region, we measure an overall planet occurrence rate of $15.4^{+1.6}_{-1.5}\,\rm per\,cent$ and a hot Jupiter occurrence rate of $0.42^{+0.16}_{-0.12}\,\rm per\,cent$. Our results establish an improved foundation for constraining theoretical models of exoplanet populations.

Fields of Study & Subjects

Stellar planetary and galactic studies Astronomy and Astrophysical Research Educational Leadership and Practices

Publication details

Journal / source
Monthly Notices of the Royal Astronomical Society
Publisher
Oxford University Press (OUP)
Volume
546
Issue
2
Publication date
7 January 2026
Language
EN