[Method of irradiating bioobjects and results of dosimetric measurements on the biosatellite "Cosmos-690"]. / Metodika oblucheniia bioob''ektov i rezul'taty dozimetricheskikh izmerenii na biosputnike "Kosmos-690".

The paper describes the design and experimental conditions of rat irradiation aboard the biosatellite Cosmos-690. An essential dose gradient due to different distances between the gamma-source and irradiated rats as well as due to the presence of construction components and equipment in the beam was made up by a special dose-equilibrating filter. The spectral distribution of scattered radiation reached maximum in the region of 0.1--0.3 Mev. The average dosage in the location of the main group of animals was 800 +/- 85 rad and that in the location of an additional group was 220 +/- 25 rad.

Irradiation of bio-objects aboard the Cosmos 690 biosatellite.

Animals on the Cosmos 690 were exposed to Cs 137 gamma-radiation of 320 curies. The on board emitter was a spherical container made of tungsten alloy with a gamma source placed in the centre. A special dose filter provided a uniform +/-10% distribution of the dose field. Animal containers were equipped with thermoluminescent dosimeters. Radiation was monitored by an on-board dosimeter and displayed. The emitter was controlled by commands from the ground. On the tenth flight day the emitter was turned on and bio-objects were exposed for 24 hours. The dose received by bio-objects located in different areas of the biosatellite varied from 200 to 1000 rad. The flight experiment confirmed entirely the reliability of the radiation system.