The Optical Design of CHARIS: An Exoplanet IFS for the Subaru Telescope

Mary Anne Peters-Limbach; Tyler D. Groff; N. Jeremy Kasdin; Dave Driscoll; Michael Galvin; Allen Foster; Michael A. Carr; Dave LeClerc; Rad Fagan; Michael W. McElwain; Gillian Knapp; Timothy Brandt; Markus Janson; Olivier Guyon; Nemanja Jovanovic; Frantz Martinache; Masahiko Hayashi; Naruhisa Takato

doi:10.1117/12.2024070

arXiv · 1309.3586

The Optical Design of CHARIS: An Exoplanet IFS for the Subaru Telescope

Mary Anne Peters-Limbach·Tyler D. Groff·N. Jeremy Kasdin·Dave Driscoll·Michael Galvin·Allen Foster·Michael A. Carr·Dave LeClerc·Rad Fagan·Michael W. McElwain·Gillian Knapp·Timothy Brandt·Markus Janson·Olivier Guyon·Nemanja Jovanovic·Frantz Martinache·Masahiko Hayashi·Naruhisa Takato

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Abstract

High-contrast imaging techniques now make possible both imaging and spectroscopy of planets around nearby stars. We present the optical design for the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), a lenslet-based, cryogenic integral field spectrograph (IFS) for imaging exoplanets on the Subaru telescope. The IFS will provide spectral information for 138x138 spatial elements over a 2.07 arcsec x 2.07 arcsec field of view (FOV). CHARIS will operate in the near infrared (lambda = 1.15 - 2.5 microns) and will feature two spectral resolution modes of R = 18 (low-res mode) and R = 73 (high-res mode). Taking advantage of the Subaru telescope adaptive optics systems and coronagraphs (AO188 and SCExAO), CHARIS will provide sufficient contrast to obtain spectra of young self-luminous Jupiter-mass exoplanets. CHARIS will undergo CDR in October 2013 and is projected to have first light by the end of 2015. We report here on the current optical design of CHARIS and its unique innovations.

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Mary Anne Peters-Limbach, Tyler D. Groff, N. Jeremy Kasdin, Dave Driscoll, Michael Galvin, Allen Foster, Michael A. Carr, Dave LeClerc, Rad Fagan, Michael W. McElwain, Gillian Knapp, Timothy Brandt, Markus Janson, Olivier Guyon, Nemanja Jovanovic, Frantz Martinache, Masahiko Hayashi, Naruhisa Takato. 2013-09-13. The Optical Design of CHARIS: An Exoplanet IFS for the Subaru Telescope. https://doi.org/10.1117/12.2024070

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