Austrian radiation dose measurements onboard space station mir and the international space station iss - overview and comparison
Abstract
The Atominstitut of the Austrian Universities has conducted various space research missions in the last 12 years in cooperation with the Institute for Biomedical Problems in Moscow. They dealt with the exact determination of the radiation hazards for cosmonauts and the development o precise measurement devices.f Special emphasis will be laid on the last experiment on space station MIR the goal of which was the determination of the depth distribution of absorbed dose and dose equivalent in a water filled phantom. The first results from dose measurements onboard the International Space Station will also be discussed.. The phantom with a diameter of 35 cm was developed at the Institute for Biomedical Problems and had 4 channels where dosemeters can be exposed in different depths. The exp osure period covered the timeframe from May 1997 to February 1999. Thermoluminescent dosemeters (TLDs) were exposed inside the phantom, either parallel or perpendicular to the hull of the spacecraft. For the evaluation of the linear energy transfer (LET), the High Temperature Ratio (HTR) - method was applied. Based on this method a mean quality factor and, subsequently, the dose equivalent is calculated according to the Q(LET ) relationship proposed in ICRP 26. An increased contribution of neutrons could be detected inside the phantom. However the total dose equivalent did not increase over the depth of the phantom. As the first Austrian measurements on the ISS dosemeter packages were exposed for 248 days, starting in February 2001 at six different locations onboard the ISS. The Austrian dosemeter sets for this first exposure on the ISS contained 5 different kinds of passive thermoluminescent dosemeters. First results showed a position dependent absorbed dose rate and LET at the ISS. Dose rates ranged from 180 to 280 μGy/d. The differences in dose measurements onboard the 2 space stations will be discussed.
- Publication:
-
34th COSPAR Scientific Assembly
- Pub Date:
- 2002
- Bibcode:
- 2002cosp...34E2588B