Exoplanets & Exomoons

Exoplanet Occurrence Rates From Microlensing Surveys

By Keith Cowing
Status Report
October 13, 2023
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Exoplanet Occurrence Rates From Microlensing Surveys
Properties of known exoplanets in mass vs. semi-major axis plane. Color codes the detection technique: green—transits, red—radial velocity, orange—direct imaging, blue—microlensing. Data were taken from the NASA Exoplanet Archive (accessed 09/08/2023). — astro-ph.EP

The number of exoplanets detected using gravitational microlensing technique is currently larger than 200, which enables population studies.

Microlensing is uniquely sensitive to low-mass planets orbiting at separations of several astronomical units, a parameter space that is not accessible to other planet-detection techniques, as well as free-floating planets, not orbiting around any star.

In this review, we present the state-of-the-art knowledge on the demographics of exoplanets detected with microlensing, with a particular emphasis on their occurrence rates.

We also summarize the current knowledge about free-floating planets, an elusive population of objects that seem to be more common than ordinary, gravitationally bound exoplanets.

P. Mroz, R. Poleski

Comments: submitted, invited chapter for the “Handbook of Exoplanets”
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Astrophysics of Galaxies (astro-ph.GA)
Cite as: arXiv:2310.07502 [astro-ph.EP] (or arXiv:2310.07502v1 [astro-ph.EP] for this version)
Submission history
From: Przemek Mroz
[v1] Wed, 11 Oct 2023 14:00:46 UTC (390 KB)

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