Scientific Design of a High Contrast Integral Field Spectrograph for the Subaru Telescope

TL;DR

This paper discusses the design and expected scientific capabilities of CHARIS, a high-contrast integral field spectrograph for the Subaru Telescope, aimed at directly detecting and characterizing exoplanets using adaptive optics.

Contribution

It introduces the design and operational modes of CHARIS, a novel high-contrast spectrograph optimized for exoplanet detection on the Subaru Telescope.

Findings

CHARIS will operate across 0.9-2.4 microns with multiple modes.

It will enhance sensitivity for giant exoplanet discovery.

CHARIS will enable detailed atmospheric characterization.

Abstract

Ground-based telescopes equipped with adaptive-optics (AO) systems and specialized science cameras are now capable of directly detecting extrasolar planets. We present the expected scientific capabilities of CHARIS, the Coronagraphic High Angular Resolution Imaging Spectrograph, which is being built for the Subaru 8.2 m telescope of the National Astronomical Observatory of Japan. CHARIS will be implemented behind the new extreme adaptive optics system at Subaru, SCExAO, and the existing 188-actuator system AO188. CHARIS will offer three observing modes over near-infrared wavelengths from 0.9 to 2.4 microns (the y-, J-, H-, and K-bands), including a low-spectral-resolution mode covering this entire wavelength range and a high-resolution mode within a single band. With these capabilities, CHARIS will offer exceptional sensitivity for discovering giant exoplanets, and will enable detailed characterization of their atmospheres. CHARIS, the only planned high-contrast integral field spectrograph on an 8m-class telescope in the Northern Hemisphere, will complement the similar instruments such as Project 1640 at Palomar, and GPI and SPHERE in Chile.