RADIATION ENVIRONMENT MEASUREMENTS WITH THE COSMIC-RAY EXPERIMENTS ON-BOARD THE KITSAT-1 AND POSAT-1 MICRO-SATELLITES

The success of the Cosmic Radiation Environment and Dosimetry (CREDO) experiment carried on-board the UoSAT-3 micro-satellite (launched in 1 990) has lead to the development of a new: instrument called the Cosmi c-Ray Experiment (CRE) which has flown on-board the KITSAT-1 and PoSAT -1 micro-satellites, launched in 1992 and 1993 respectively. The resul ts from both CRE instruments show excellent agreement with those of CR EDO for the galactic cosmic-ray environment. However, there are some d ifferences in the CRE and CREDO response to the trapped proton environ ment of the South Atlantic Anomaly which can be explained by the diffe rences in the detector response time. The fit between the flight resul ts and predictions from the standard models is generally good, but som e differences are noted. The CRE and CREDO instruments should provide continuous coverage of the near-Earth radiation environment across a c omplete solar cycle. This is important in view of the dynamic nature o f the radiation environment - as amply demonstrated by the results fro m the CRRES spacecraft [1].