Balloon-borne far-infrared Michelson interferometer for atmospheric emission studies.

A series of far-ir Michelson interferometers utilizing the rapid-scanning technique have been designed and built for balloon-borne measurement of the emission spectrum of the stratosphere. Design criteria for such instrumentation are presented, and details of the evolution of these designs are discussed, including liquid helium-cooled bolometer detector systems, internal blackbody calibration, and atmospheric limb-scanning. Stratospheric emission spectra between 30 cm(-1) and 110 cm(-1) at a resolution of 0.07 cm(-2) are presented as examples of results taken at balloon altitudes, and the merits of this type of instrumentation for monitoring stratospheric trace gas constituent concentrations are discussed.