Recent and Upcoming Upgrades for MIRC-X and MYSTIC on the CHARA Array

Noura Ibrahim; Mayra Gutierrez; John D. Monnier; Stefan Kraus; Jean-Baptiste Le Bouquin; Narsireddy Anugu; Theo ten Brummelaar; Sorabh Chhabra; Isabelle Codron; Julien Dejonghe; Aaron Labdon; Daniel Lecron; Daniel Mortimer; Denis Mourard; Gail Schaefer; Benjamin Setterholm; Manuela Arnó; Andrea Bianco; Michele Frangiamore; Laurent Jocou

arXiv · 2408.04038

Recent and Upcoming Upgrades for MIRC-X and MYSTIC on the CHARA Array

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Abstract

MIRC-X and MYSTIC are six-telescope near-infrared beam (1.08-2.38 ${\mu}$m) combiners at the CHARA Array on Mt Wilson CA, USA. Ever since the commissioning of MIRC-X (J and H bands) in 2018 and MYSTIC (K bands) in 2021, they have been the most popular and over-subscribed instruments at the array. Observers have been able to image stellar objects with sensitivity down to 8.1 mag in H and 7.8 mag in K-band under the very best conditions. In 2022 MYSTIC was upgraded with a new ABCD mode using the VLTI/GRAVITY 4-beam integrated optics chip, with the goal of improving the sensitivity and calibration. The ABCD mode has been used to observe more than 20 T Tauri stars; however, the data pipeline is still being developed. Alongside software upgrades, we detail planned upgrades to both instruments in this paper. The main upgrades are: 1) Adding a motorized filter wheel to MIRC-X along with new high spectral resolution modes 2) Updating MIRC-X optics to allow for simultaneous 6T J+H observations 3) Removing the warm window between the spectrograph and the warm optics in MYSTIC 4) Adding a 6T ABCD mode to MIRC-X in collaboration with CHARA/SPICA 5) Updating the MIRC-X CRED-ONE camera funded by Prof. Kraus from U. Exeter 6) Carrying out science verification of the MIRC-X polarization mode 7) Developing new software for ABCD-mode data reduction and more efficient calibration routines. We expect these upgrades to not only improve the observing experience, but also increase the sensitivity by 0.4 mag in J+H-bands, and 1 mag in K-band.

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Noura Ibrahim, Mayra Gutierrez, John D. Monnier, Stefan Kraus, Jean-Baptiste Le Bouquin, Narsireddy Anugu, Theo ten Brummelaar, Sorabh Chhabra, Isabelle Codron, Julien Dejonghe, Aaron Labdon, Daniel Lecron, Daniel Mortimer, Denis Mourard, Gail Schaefer, Benjamin Setterholm, Manuela Arnó, Andrea Bianco, Michele Frangiamore, Laurent Jocou. 2024-08-07. Recent and Upcoming Upgrades for MIRC-X and MYSTIC on the CHARA Array. https://arxiv.org/abs/2408.04038

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