Two Light Paths:
One light path for short wavelengths
(45 - 110 microns) and one light path for long wavelengths
(110 - 210 microns). This will allow simultaneous
observations in the two bands.
Simultaneous Spatial Imaging:
35" x 35" and 70" x 70" field of view,
for each light path respectively.
Each field of view resolved with 5 x 5 pixels.
3-D Imaging Capability:
Simultaneous imaging in both spatial
(2-D on the plane of the sky) and spectral
(in different wavelength channels) domains
for all 25 pixels in each band.
Good Spectral Resolution:
Spectral resolution of R = 1000 - 2000 in each band
(this corresponds to a velocity resolution of 150 - 300 km/s).
Each of the 25 spatial pixels has 16 pixels of spectral
This resolution is required to resolve spectral features in
astronomical sources, especially galaxies.
Instantaneous Spectral Coverage:
Spectral band coverage of
1500 km/s will allow FIFI LS to cover the
velocity distribution in entire galaxies and provide
good baseline coverage on both sides of any spectral line
in both bands.
2 Ge:Ga Photoconductor Arrays:
25x16 pixels each (an unstressed array for short wavelengths,
40 - 110 Microns, and a stressed array for long wavelengths,
110 - 220 Microns).
Long-Slit, Littrow-Mount Grating Spectrographs:
One for each spectrometer, operating in 1st or 1st/2nd order
(for the short and long wavelength bands respectively).