ABSTRACT
In modelling the action of the high energy component of space radiation in a space ship, the secondary radiation resulting from the interaction of 76 GeV protons with a target was used. The radiation flow consisted of neutrons, mesons of different kinds and charges, protons and gamma-quanta of wide energy spectrum. We studied the influence of radiation on the survival of E. coli B and T4Br+ bacteriophage, on the growth, dry weight and survival of Vicia faba, on the frequency of chromosome aberrations, and number of cells with abnormal mitoses, on the rate of post-irradiation recovery according to these characteristics, and also on the yield of the r-mutants of T4Br+ bacteriophage, their distribution and biochemical identification. The probability of strong interactions with intra-nuclear cascade processes was minor. Their action on the background of the main mass of radiation with an RBE of less than 1 could be considerably masked. Nevertheless, the RBE of combined secondary radiation was sufficiently greater than 137Cs radiation; from approximate curves, it was from 1.2 to 4.0 times as great and in single experimental points it was more than 5. The spectrum of mutation was also different.