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arXiv · 1610.05269

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

Steve B. Howell·Mark E. Everett·Elliott P. Horch·Jennifer G. Winters·Lea Hirsch·Dan Nusdeo·Nicholas J. Scott
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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.

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Steve B. Howell, Mark E. Everett, Elliott P. Horch, Jennifer G. Winters, Lea Hirsch, Dan Nusdeo, Nicholas J. Scott. 2016-09-11. Speckle Imaging Excludes Low-Mass Companions Orbiting the Exoplanet Host Star TRAPPIST-1. https://doi.org/10.3847/2041-8205%2F829%2F1%2Fl2

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