Speckle Imaging Excludes Low-Mass Companions Orbiting the Exoplanet Host Star TRAPPIST-1

TL;DR

High-resolution speckle imaging of TRAPPIST-1 with Gemini-South rules out the presence of low-mass stellar or brown dwarf companions within 0.32 to 14.5 AU, confirming it as a single star.

Contribution

This study provides the highest resolution images of TRAPPIST-1, setting stringent limits on potential low-mass companions and confirming its solitary nature.

Findings

No stellar companions detected within 14.5 AU

Speckle imaging achieves 0.32 AU spatial resolution

TRAPPIST-1 is confirmed as a single star

Abstract

We have obtained the highest resolution images available of TRAPPIST-1 using the Gemini-South telescope and our speckle imaging camera. Observing at 692 and 883 nm, we reached the diffraction limit of the telescope providing a best resolution of 27 mas or, at the distance of TRAPPIST-1, a spatial resolution of 0.32 AU. Our imaging of the star extends from 0.32 to 14.5 AU. We show that to a high confidence level, we can exclude all possible stellar and brown dwarf companions, indicating that TRAPPIST-1 is a single star.