A NEAR-INFRARED AIRGLOW RADIOMETER WITH A LN(2) COOLED GE SENSOR FOR ROCKET EXPERIMENTS

A high sensitive airglow radiometer in the near infrared region for a rocket observation was developed. The radiometer is equipped with a Ge sensor cooled by liquid nitrogen. In comparison with a PbS sensor previously used, the Ge sensor has various advantages such as short response time, high sensitivity in the near infrared region and unnecessity of a high voltage. A liquid nitrogen tank of 500 cc capacity is set in a vacuum vessel. The tank is supported with 16 GFRP belts to minimize thermal coupling with the vessel. The sensor is cooled to 88K and no temperature variation is found for more than 2 hours after the tank is filled with liquid nitrogen. A rocket experiment of the O-2 1.27 mu m nightglow was carried out by using the developed radiometer on board the S-310-20 rocket launched from Kagoshima Space Center, Japan on January 28, 1990. The observation was successful, and excellent data were obtained.