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

TL;DR

The paper reports on the performance of the SCExAO instrument on the Subaru telescope, demonstrating high-quality adaptive optics corrections and successful early science results including direct imaging and spectral analysis of exoplanets and disks.

Contribution

It presents the current capabilities of SCExAO, including high Strehl ratios and contrast performance, and showcases early scientific results with direct imaging and spectroscopy of exoplanets.

Findings

SCExAO achieves H band Strehl ratios up to ~0.9.

CHARIS provides high S/N spectra of directly-imaged exoplanets.

Re-evaluation of claimed protoplanets around LkCa 15.

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 We also show how recently published as well as unpublished observations of LkCa 15 lead to a re-evaluation of its claimed protoplanets.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.