A mid-infrared (4 to 27 micron meters) imaging echelle spectrometer will be built for the Keck Telescope. The instrument, dubbed SADIE (San Diego Imaging Echelle), is to be a general purpose user instrument serving all of the University of California, Caltech, and University of Hawaii astronomical community as well as their collaborators. It is the only dedicated infrared spectroscopic instrument currently proposed for the Keck Telescope. Due to the huge light gathering power and unprecedented mid-IR spatial resolution of the Keck Telescope, SADIE will allow its user community to make significant advances in many areas of astrophysical interest. Such areas include, but are not restricted to, studies of (1) active galaxies and QSOs, (2) nearby normal galaxies, (3) star formation, (4) planetary nebulae (5) interstellar and circumstellar matter, (6) novae and supernovae, (7) the dynamics of stellar systems, and (8) solar systems objects. Because it is a general purpose instrument, SADIE will use a variety of gratings, including a low order echelle in Littrow configuration. SADIE's spectrometer optics feed a blocked impurity band conduction, direct readout array focal plane. Because of SADIE's versatile design, it will be capable of broad and narrow band imaging as well as spectroscopy at spectral resolutions of 100, 800, and 7000 at two plate scales, 0.4 and 0.2 arcsec per pixel. The 20 X 64 element array, built by Aerojet ElectroSystems, will provide background limited performance at all spectral resolutions. SADIE is designed to allow the incorporation of much larger arrays, a commitment by Aerojet exists to provide UCSD with samples of their new 100 X 100 pixel, capacitive feedback IBC arrays. If these arrays prove suitable, they will provide a natural upgrade for SADIE.
