Field imaging far-infrared line spectrometer FIFI LS
Abstract
We present our design for a field-imaging, far-infrared line spectrometer for the SOFIA airborne observatory. The instrument will employ two parallel, medium resolution (R approximately 1700) grating spectrometers for simultaneous observations in the wavelength bands 42 - 110 micrometer and 110 - 210 micrometer. The Littrov mounted gratings are operated in first and second order. Large stressed and unstressed 16 X 25 pixel Ge:Ga photoconductor arrays are operated in the spectrometer channel, providing good spectral coverage with high responsivity. Image slicers in each spectrometer branch redistribute the 5 X 5 pixel field of view along the 1 X 25 pixel entrance slits of the spectrographs, providing both, spatial and spectral multiplexing. Thus, for each of the 25 spatial pixels, we are able to cover a velocity range of approximately 1500 km/s around a selected far infrared line, with an estimated sensitivity of approximately 2 X 10-15 W Hz-1/2 per pixel.
- Publication:
-
Infrared Spaceborne Remote Sensing VII
- Pub Date:
- December 1999
- DOI:
- 10.1117/12.372662
- Bibcode:
- 1999SPIE.3759...86R