Terahertz Technology for ESPRIT - A Far-Infrared Space Interferometer

In the Terahertz regime the angular (and sometimes spectral) resolution of observing facilities is still very restricted despite the fact that this frequency range has become of prime importance for modern astrophysics. ALMA (Atacama Large Millimeter Array) with its superb sensitivity and angular resolution will only cover frequencies up to about 1 THz, while the HIFI instrument for ESA’a Herschel Space Observatory will provide limited angular resolution (10 to 30 arcsec) up to 2 THz. Observations of regions with star and planet formation require extremely high angular resolution as well as frequency resolution in the full THz regime. In order to open these regions for high-resolution astrophysics we propose a heterodyne space interferometer mission, ESPRIT (Exploratory Submm Space Radio-Interferometric Telescope), for the Terahertz regime inaccessible from ground and outside the operating range of the James Webb Space Telescope (JWST). ESPRIT will employ heterodyne receivers from 0.5 to 6 THz. The ESPRIT mission concept is described with an emphasis on Terahertz heterodyne receivers and cooling. The required technology development of mixers, local oscillators and integrated systems will be outlined