Detecting the Signatures of Uranus and Neptune

TL;DR

This paper evaluates the detectability of Uranus and Neptune analogues around stars using radial velocity, transit, and photometric methods, highlighting current limitations and prospects for future detection of ice giants beyond the snow line.

Contribution

It provides a simulation-based assessment of detecting ice giants like Uranus and Neptune around stars, comparing various observational techniques and their effectiveness.

Findings

Radial velocity sensitivity limits for ice giants.

Transit and photometric detection challenges.

Comparison of detection prospects with astrometry and imaging.

Abstract

With more than 15 years since the the first radial velocity discovery of a planet orbiting a Sun-like star, the time baseline for radial velocity surveys is now extending out beyond the orbit of Jupiter analogs. The sensitivity to exoplanet orbital periods beyond that of Saturn orbital radii however is still beyond our reach such that very few clues regarding the prevalence of ice giants orbiting solar analogs are available to us. Here we simulate the radial velocity, transit, and photometric phase amplitude signatures of the solar system giant planets, in particular Uranus and Neptune, and assess their detectability. We scale these results for application to monitoring low-mass stars and compare the relative detection prospects with other potential methods, such as astrometry and imaging. These results quantitatively show how many of the existing techniques are suitable for the detection of ice giants beyond the snow line for late-type stars and the challenges that lie ahead for the detection true Uranus/Neptune analogues around solar-type stars.