FIFI-LS instrument

Far Infrared Field-Imaging Line Spectrometer (FIFI-LS)

Facility-class Science Instrument
Principal Investigator:
Alfred Krabbe
Deutsches SOFIA Institut (DSI)
Universität Stuttgart - Institut für Raumfahrtsysteme, Stuttgart, Germany
Instrument Team Website

FIFI-LS is an integral field, far-infrared spectrometer. The instrument includes two independent grating spectrometers sharing a common field of view (FOV). The short wavelength spectrometer (blue channel) operates in the 51 – 120 μm wavelength region, and the long wavelength spectrometer (red channel) covers 115 – 200 μm. Each channel has a 5x5 pixel projection onto the sky, with the centers offset by 10”. The blue channel has a pixel size of 6”x6” yielding a 0.5 arcmin-square FOV, and the red channel has a pixel size of 12”x12” yielding a 1.0 arcmin-square FOV. Each spectrometer has a 25x16 pixel detector of Germanium Gallium-doped photoconductors. The 5x5 pixels FOV are re-organized along a 25x1 line, and then are dispersed by the spectrometers on 16 pixels in the spectral dimension. The spectral resolution ranges from 600 to 2,000 dependent on the observed wavelength, with higher values towards the long wavelength ends of each spectrometer.

Examples of FIFI-LS scientific observations and summary of specifications: FIFI-LS Flyer

Information applicable to the observing cycles can be found in their respective versions of the Observer's Handbook. Be sure that you are referencing the correct version of the handbook!

The latest sensitivities estimates can be found here and on SITE.

The FIFI-LS Guest Observer (GO) Data Handbook describes FIFI-LS data products, processing steps, calibration procedures, and known issues.

Primary References

Use when citing SOFIA/FIFI-LS results.

"FIFI-LS: The Field-Imaging Far-Infrared Line Spectrometer on SOFIA"
Fischer, et al., 2018, JAI, 7, 1840003-556.
DOI: 10.1142/S2251171718400032; ADS Bibliographic Code: 2018JAI.....740003F

"Spectral and Spatial Characterization and Calibration of FIFI-LS — The Field Imaging Spectrometer on SOFIA"
Colditz S. et al., 2018, JAI, Volume 7, 1840004-(12)556.
DOI: 10.1142/S2251171718400044; ADS Bibliographic Code: 2018JAI.....740004C 

Additional References

"FIFI-LS: the Facility Far-infrared Spectrometer for SOFIA"
Klein, R., et al., 2014, ProcSPIE, 9147, 91472X.
DOI: 10.1117/12.2055371; ADS Bibliographic Code: 2014SPIE.9147E..2XK

"FIFI-LS Getting Ready to Fly Aboard SOFIA"
Klein, R., et al., 2010, ProcSPIE 7735, 77351T.
DOI: 10.1117/12.856530 [pdf]

"FIFI-LS: The Far-infrared Integral Field Spectrometer for SOFIA"
Klein, R., et al., 2006, ProcSPIE 6269, 62691F.
DOI: 10.1117/12.671505 [pdf]

"Characterizing The System Performance of FIFI-LS: The Field-imaging Far-infrared Line Spectrometer for SOFIA,"
Raab et al., 2006, ProcSPIE 6269, 62691G.
DOI: 10.1117/12.671483 [pdf]

"FIFI-LS: a far-infrared 3D spectral imager for SOFIA"
Looney et al., 2003, Proc.SPIE, 4857, 47.
DOI: 10.1117/12.458631

"FIFI-LS: The Optical Design and Diffraction Analysis,"
Raab et al., 2003, ProcSPIE 4857, 166.
DOI: 10.1117/12.458629 [pdf]