A Pathfinder for Imaging Extrasolar Earths from the Ground

Thayne Currie

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arXiv · 1906.02214

A Pathfinder for Imaging Extrasolar Earths from the Ground

Thayne Currie

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Abstract

The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) project is an instrument on the Subaru telescope that is pushing the frontiers of what is possible with ground-based high-contrast imaging of extrasolar planets. The system features key breakthroughs in wavefront sensing and coronagraphy to yield extremely high Strehl ratio corrections and deep planet-to-star contrasts, even for optically faint stars. SCExAO is coupled to a near-infrared integral field spectrograph -- CHARIS -- yielding robust planet spectral characterization. In its first full year of operations, SCExAO has already clarified the properties of candidate companions around $κ$ And, LkCa 15, and HD 163296, showing the former to be a likely low-gravity, planet-mass object and the latter two to be misidentified disk signals. SCExAO's planet imaging capabilities in the near future will be further upgraded; the system is emerging as a prototype of the kind of dedicated planet-imaging system that could directly detect an Earth-like planet around a nearby low-mass star with Extremely Large Telescopes like the Thirty Meter Telescope.

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Thayne Currie. 2019-06-05. A Pathfinder for Imaging Extrasolar Earths from the Ground. https://arxiv.org/abs/1906.02214

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