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This content will become publicly available on August 26, 2023

Title: MYSTIC: a high angular resolution K-band imager at CHARA
The Michigan Young STar Imager at CHARA (MYSTIC) is a K-band interferometric beam combining instrument funded by the United States National Science Foundation, designed primarily for imaging sub-au scale disk structures around nearby young stars and to probe the planet formation process. Installed at the CHARA array in July 2021, with baselines up to 331 meters, MYSTIC provides a maximum angular resolution of λ/2B ∼ 0.7 mas. The instrument injects phase corrected light from the array into inexpensive, single-mode, polarization maintaining silica fibers, which are then passed via a vacuum feedthrough into a cryogenic dewar operating at 220 K for imaging. MYSTIC utilizes a high frame rate, ultra-low read noise SAPHIRA detector, and implements two beam combiners: a 6-telescope image plane beam combiner, based on the MIRC-X design, for targets as faint as 7.7 Kmag, as well as a 4-telescope integrated optic beam-combiner mode using a spare chip leftover from the GRAVITY instrument. MYSTIC is co-phased with the MIRC-X (J+H band) instrument for simultaneous fringe-tracking and imaging, and shares its software suite with the latter to allow a single observer to operate both instruments. Herein, we present the instrument design, review its operational performance, present early commissioning science observations, and more » propose upgrades to the instrument that could improve its K-band sensitivity to 10th magnitude in the near future. « less
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Mérand, Antoine; Sallum, Stephanie; Sanchez-Bermudez, Joel
Award ID(s):
1506540 1909165
Publication Date:
Journal Name:
SPIE Astronomical Instrumentation
Page Range or eLocation-ID:
Sponsoring Org:
National Science Foundation
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