IRCS grism spectroscopy
The camera section of IRCS provides a number of grisms which provide a low resolution (typically R < 1000) spectroscopic capability. Slit widths of 0.1-0.9'' are available, although there is significant light loss with the narrowest slits unless Adaptive Optics is used.
IRCS relies on AO188 for guiding without a separate autoguider. Please refer to the Guide to exposure time page for more information.
There is a damaged portion within Reflective 4 slit which corresponds to 0."15 slit, and 0."3 slit for 20 mas, and 52 mas, respetively. It is stronlgy suggested not to use these slits. In general, 0."225 slits are recommended to be used as alternatives.