The SEEDS High Contrast Imaging Survey of Exoplanets around Young Stellar Objects

TL;DR

This paper reports high-contrast imaging observations of 68 young stellar objects to detect and analyze exoplanets and companions, providing insights into planet formation around very young stars.

Contribution

It presents the first high-contrast imaging survey of very young stellar objects, detecting new companions and setting constraints on planet formation at early stellar ages.

Findings

Detected a new stellar companion to HIP 79462.

Confirmed substellar objects GQ Lup b and ROXs 42B b.

Identified six companion candidates for follow-up.

Abstract

We present high-contrast observations of 68 young stellar objects (YSOs) explored as part of the SEEDS survey on the Subaru telescope. Our targets are very young ($<$10 Myr) stars, which often harbor protoplanetary disks where planets may be forming. We achieve a typical contrast of $\sim$$10^{-4}$--$10^{-5.5}$ at an angular distance of 1\arcsec\ from the central star, corresponding to typical mass sensitivities (assuming hot-start evolutionary models) of $\sim$10 ${\rm M_J}$ at 70 AU and $\sim$6 ${\rm M_J}$ at 140 AU. We detected a new stellar companion to HIP 79462 and confirmed the substellar objects GQ Lup b and ROXs 42B b. An additional six companion candidates await follow-up observations to check for common proper motion. Our SEEDS YSO observations probe the population of planets and brown dwarfs at the very youngest ages; these may be compared to the results of surveys targeting somewhat older stars. Our sample and the associated observational results will help enable detailed statistical analyses of giant planet formation.