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iSHELL is a high-resolution 1.1-5.3 micron spectrograph built at the Institute for Astronomy (IfA), for the NASA Infrared Telescope Facility (IRTF) on Maunakea. The instrument saw first light in Sept. 2016. iSHELL uses a silicon immersion grating to achieve high spectral resolution in a relativly compact instrument. iSHELL's detectors are a Raytheon Aladdin 3 512x512 InSb array in the guider and a Teledyne 2048x2048 Hawaii-2RG array for the spectrograph. Astronomical Research Cameras, Inc. controllers run both arrays. iSHELL's wavelength range is covered in 17 discrete settings of the cross disperser turret, while custom wavelength settings are available. A data reduction tool is available via SpeXtool5.
Slit widths: 0.375", 0.75", 0.8", 1.5" and 4.0"
J, H, and K-bands: R~75,000 matched to 0.375x5" slit, 3 cross disperser settings per band