Long-term measurements of the neutron flux aboard the ''MIR''-type space station

In order to monitor the radiation environment, radiometric instruments were accommodated aboard the ''Mir'' and most of the ''Salyut'' space stations. These instruments registered the neutron flux in the energy range from thermal to several MeV. This paper briefly describes the instrument and contains results of the neutron flux measurements performed during 1975-1980. The results reported here were compared with measurements obtained on board the OGO-6 orbital observatory. Measurement data obtained aboard the Salyut-6 space station enabled a determination to be made of the integrated neutron flux distribution (mainly local) in the region of the South Atlantic magnetic anomaly and estimation of the albedo neutron flux on the geomagnetic equator (0.06 ± 0.02 cm-2 s-1) and on the 45o and 60o geomagnetic latitude (0.43±0.1 and 0.58±0.15 cm-2 s-1, respectively). The angular distribution of albedo neutrons is described by the following expression: f(θ)=1+0.615 cos4θ. (author)