MIRAC-5: A ground-based mid-IR instrumentwith the potential to detect ammonia in gas giants

TL;DR

MIRAC-5 is a ground-based mid-infrared instrument with advanced detectors and adaptive optics, capable of high-resolution imaging and potential ammonia detection in gas giants, complementing space telescopes like JWST.

Contribution

This paper introduces MIRAC-5 with a new GeoSnap detector, enabling high-resolution mid-infrared observations and the first ammonia detection in exoplanet atmospheres from the ground.

Findings

Potential to detect ammonia in gas giant atmospheres.

First continuum mid-infrared measurements for several gas giants.

High quantum efficiency and low noise of the GeoSnap detector.

Abstract

We present the fifth incarnation of the Mid-Infrared Array Camera (MIRAC-5) instrument which will use a new GeoSnap (3 - 13 microns) detector. Advances in adaptive optics (AO) systems and detectors are enabling ground-based mid-infrared systems capable of high spatial resolution and deep contrast. As one of the only 3 - 13 micron cameras used in tandem with AO, MIRAC-5 will be complementary to the James Webb Space Telescope (JWST) and capable of characterizing gas giant exoplanets and imaging forming protoplanets (helping to characterize their circumplanetary disks). We describe key features of the MIRAC-5 GeoSnap detector, a long-wave Mercury-Cadmium-Telluride (MCT) array produced by Teledyne Imaging Sensors (TIS), including its high quantum efficiency (> 65%), large well-depth, and low noise. We summarize MIRAC-5's important capabilities, including prospects for obtaining the first continuum mid-infrared measurements for several gas giants and the first 10.2-10.8 micron NH3 detection in the atmosphere of the warm companion GJ 504b (Teff ~550 K) within 8 hours of observing time. Finally, we describe plans for future upgrades to MIRAC-5 such as adding a coronagraph. MIRAC-5 will be commissioned on the MMT utilizing the new MAPS AO system in late 2022 with plans to move to Magellan with the MagAO system in the future.