Performance and Early Science with the Subaru Coronagraphic Extreme Adaptive Optics Project

Thayne Currie; Olivier Guyon; Julien Lozi; Tyler Groff; N. Jeremy Kasdin; Frantz Martinache; Timothy D Brandt; Jeffrey Chilcote; Christian Marois; Benjamin Gerard; Nemanja Jovanovic; Sebastien Vievard

arXiv · 1909.10522

Performance and Early Science with the Subaru Coronagraphic Extreme Adaptive Optics Project

Thayne Currie·Olivier Guyon·Julien Lozi·Tyler Groff·N. Jeremy Kasdin·Frantz Martinache·Timothy D Brandt·Jeffrey Chilcote·Christian Marois·Benjamin Gerard·Nemanja Jovanovic·Sebastien Vievard

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Abstract

We describe the current performance of the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument on the Subaru telescope on Maunakea, Hawaii and present early science results for SCExAO coupled with the CHARIS integral field spectrograph. SCExAO now delivers H band Strehl ratios up to $\sim$ 0.9 or better, extreme AO corrections for optically faint stars, and planet-to-star contrasts rivaling that of GPI and SPHERE. CHARIS yield high signal-to-noise detections and 1.1--2.4 $\mu m$ spectra of benchmark directly-imaged companions like HR 8799 cde and kappa And b that clarify their atmospheric properties. We also show how recently published as well as unpublished observations of LkCa 15 lead to a re-evaluation of its claimed protoplanets. Finally, we briefly describe plans for a SCExAO-focused direct imaging campaign to directly image and characterize young exoplanets, planet-forming disks, and (later) mature planets in reflected light.

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Thayne Currie, Olivier Guyon, Julien Lozi, Tyler Groff, N. Jeremy Kasdin, Frantz Martinache, Timothy D Brandt, Jeffrey Chilcote, Christian Marois, Benjamin Gerard, Nemanja Jovanovic, Sebastien Vievard. 2019-09-23. Performance and Early Science with the Subaru Coronagraphic Extreme Adaptive Optics Project. https://arxiv.org/abs/1909.10522

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