High-resolution survey for planetary companions to young stars in the Taurus Molecular Cloud

TL;DR

This study used high-resolution infrared imaging with adaptive optics to search for planetary companions around young stars in Taurus, constraining the frequency of wide-separation massive planets.

Contribution

It applied advanced imaging techniques to set new limits on the occurrence of massive planets at wide separations around young stars.

Findings

No new faint companions detected.

Less than 20% of stars host >2 MJ planets beyond 10 AU.

Achieved contrast of ~6-8 magnitudes at small separations.

Abstract

Direct imaging in the infrared at the diffraction limit of large telescopes is a unique probe of the properties of young planetary systems. We survey 55 single class I and class II stars in Taurus in the L' filter using natural and laser guide star adaptive optics and the near-infrared camera (NIRC2) of the Keck II telescope, in order to search for planetary mass companions. We use both reference star differential imaging and kernel phase techniques, achieving typical 5-sigma contrasts of ~6 magnitudes at separations of 0.2" and ~8 magnitudes beyond 0.5". Although we do not detect any new faint companions, we constrain the frequency of wide separation massive planets, such as HR 8799 analogues. We find that, assuming hot-start models and a planet distribution with power-law mass and semi-major axis indices of -0.5 and -1, respectively, less than 20% of our target stars host planets with masses >2 MJ at separations >10 AU.