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

@article{Howell2016SpeckleIE,
title={Speckle Imaging Excludes Low-Mass Companions Orbiting the Exoplanet Host Star TRAPPIST-1},
author={Steve B. Howell and Mark E. Everett and Elliott P. Horch and Jennifer G. Winters and Lea A. Hirsch and Daniel A. Nusdeo and Nicholas J. Scott},
journal={arXiv: Earth and Planetary Astrophysics},
year={2016}
}
• Published 11 September 2016
• Physics, Geology
• arXiv: Earth and Planetary Astrophysics
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…

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