UIST is a 1-5um imager-spectrometer with a 1024×1024 InSb array. The instrument is designed to switch quickly and accurately between imaging and spectroscopic modes; spectroscopic targets are acquired by first imaging the field. The mechanical layout shows the instrument’s key features.
In imaging mode ,there are two plate scales available, 0.12 arcsec per pixel or 0.06 arcsec per pixel, giving fields of view of 2×2 or 1×1 arcminute; subarray readout is possible. In spectroscopy mode only the 0.12″/pixel camera is used, though there is a choice of slit widths, and slitless spectroscopy is now possible. Integral field spectroscopy is available via an image slicing design which provides spectroscopy of a 3.3×6.0 arcsec (rotatable) area sampled every 0.48×0.24 arcsec. Polarimetry is also available with all imaging and long-slit spectroscopy modes. Finally, coronagraphic imaging and coronagraphic imaging polarimetry is also now possible. (The Fabry-Perot interferometer for the K window is not offered with UIST but is available with UFTI. )
UIST was built at the ATC in Edinburgh. Suzie Ramsay Howat was the project scientist. The instrument was delivered to Hawaii in August 2002, commissioned in October 2002, and has been available for observing since December 2002. UIST enquiries should be addressed to the instrument scientist, Watson Varricatt.
An appropriate reference for UIST would be: Ramsay Howat S.K. et al. (11 authors), 2004, “The commissioning of and first results from the UIST imager spectrometer”, In Proc Spie 5492, UV and Gamma-Ray Space Telescope Systems, eds. Hasinger G, Turner M.J., p.1160 (ADS link). UKIRT would also welcome an acknowledgment in papers resulting from UIST observations.