Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver


CASIMIR is a sensitive submillimeter and far-infrared heterodyne receiver for SOFIA. The receiver uses sensitive superconducting tunnel junction (SIS) mixers to achieve double sideband receiver noise temperatures about 4-10 times the quantum limit. The continuously tunable local oscillators consist of HEMT power amplifiers followed by frequency multipliers.

CASIMIR will cover the 500-1500 GHz frequency range in five bands: 550 GHz, 750 GHz, 1 THz, 1.2 THz, and 1.4 THz. Four of these frequency bands can be used on a given flight. If desired, the selection of frequency bands may be changed between flights. The receiver will have an intermediate-frequency (IF) bandwidth of 4 GHz, which will be processed by a high resolution digital FFT spectrometer. Possible future enhancements include broadening the IF bandwidth, adding new higher frequency bands, and continuously incorporating the latest advancements in receiver and spectrometer technology.

This instrument will be used to study a wide range of astrophysical problems ranging from the evolution of galaxies to the birth and death of stars.

CASIMIR Performance Summary – Instrument sensitivity and resolution summary is provided to permit estimating feasibility of scientific investigations.