MICS:: A new Mid-Infrared Camera and Spectrometer for ground-based astronomy

We have developed the Mid-Infrared Camera and Spectrometer (MICS), which is optimized for ground-based observations in the N-band (7.6-13.6 mu m) atmospheric window. The MICS has two observing capabilities: imaging and long slit low-resolution spectroscopy. The major characteristics of the MICS are nearly diffraction-limited performance, both in imaging and in spectroscopy and the capability to take a spectrum of the whole N-band range with a spectral resolving power of 100. The MICS employs a state-of-the-art two-dimensional array of 128 x 128 Si:As BIB detector, an aberration-corrected concave grating, and a high-speed readout system, which allows a compact design with high sensitivity. In this paper, we describe the design of MICS, including optics, cryogenics, and electronics, and its performance when used on the United Kingdom Infrared Telescope (UKIRT). We also discuss sky noise in the N band and observational techniques for efficient mid-infrared observations.