Radiation tolerance analysis of IASI infrared detectors in the 3.4-15.5μm spectral range

摘要

IASI (Infrared Atmospheric Sounding Interferometer) is an infrared atmospheric sounder. The IASI instrument is currently operating on the Metop-A satellite (launched in October 2006). The core of the instrument is composed of a Fourier transform infrared spectrometer. The detection chain of the spectrometer includes 3 bands to cover the 3.4 to 15.5 μm spectral range. For each band, the IR detection is made by a 2 x 2 pixels array operating at ~93K. This paper presents an analysis of the radiation tolerance of the infrared detectors for each band. On ground, radiation tests have been performed to address sensitivity to gamma-rays and protons radiations. A special care has been taken to keep the detectors at cold temperature during tests. Performance evolutions (responsivity, relative spectral response, noise,... tested in CNES facilities) before and after radiations are given. First in orbit impacts of the radiations are also reviewed.