The Likelihood of Detecting Young Giant Planets with High Contrast Imaging and Interferometry

TL;DR

This paper models the formation and brightness of young giant planets to evaluate their detectability with current and future high contrast imaging and interferometry instruments.

Contribution

It provides the first detailed simulations of young giant planet brightness during formation and assesses detection probabilities with current and upcoming telescopes.

Findings

Current large telescopes have less than 0.2% chance to detect such planets in L' band.

Future instruments like METIS and VIKiNG could detect up to 8%.

Detection likelihood is low but improves with advanced instruments.

Abstract

Giant planets are expected to form at orbital radii that are relatively large compared to transit and radial velocity detections (>1 AU). As a result, giant planet formation is best observed through direct imaging. By simulating the formation of giant (0.3-5$M_{J}$) planets by core accretion, we predict planet magnitude in the near infrared (2-4 $\mu$m) and demonstrate that, once a planet reaches the runaway accretion phase, it is self-luminous and is bright enough to be detected in near infrared wavelengths. Using planet distribution models consistent with existing radial velocity and imaging constraints, we simulate a large sample of systems with the same stellar and disc properties to determine how many planets can be detected. We find that current large (8-10m) telescopes have, at most a 0.2% chance of detecting a core accretion giant planet in the L' band and 2% in the K band for a typical solar type star. Future instruments such as METIS and VIKiNG have higher sensitivity and are expected to detect exoplanets at a maximum rate of 2% and 8% respectively.