BSMILES - A Balloon borne Superconducting Submillimeter-Wave Limb-Emission Sounder for Atmospheric Research

A Balloon-borne Superconducting Submillimeter-Wave Limb-Emission Sounder (BSMILES) to measure vertical profile of stratospheric minor constituents was developed. BSMILES carries a 300mm-diameter offset parabolic antenna, a 650-GHz heterodyne SIS receiver, and an acousto-optical spectrometer. The SIS junction chip consists of two Nb/A10x/Nb junctions connected by a tuning inductance in parallel. The DSB receiver noise temperature of the SIS receiver is about 200 K. BSMILES was launched from Sanriku Balloon Center of Japan Aerospace Exploration Agency on August 30, 2003. The gondola was carried to an altitude of 31-33.8 km by a balloon of 80,000 m in volume and the observations were made for 3 hours. All systems operated normally and the emission line spectra of ozone at 650.733 GHz and chlorine monoxide at 649.45 GHz were measured. After the observations, the gondola was dropped and splashed on the Pacific Ocean and retrieved. Almost all systems were waterproofed and it turns out that they are reusable.