Described is the Liulin-5 active dosimetric telescope designed for measurement of the space radiation dose depth-distribution in a human phantom on the Russian Segment of the International Space Station (ISS). The Liulin-5 experiment is a part of the international project MATROSHKA-R on ISS. The MATROSHKA-R project is aimed to study the depth- dose distribution at the sites of critical organs of the human body, using models of human body-anthropomorphic ant spherical tissue-equivalent phantoms. The aim of Liulin-5 experiment is a long term (4–5 years) investigation of the radiation environment dynamics inside the spherical tissue-equivalent phantom, mounted in different compartments. Energy deposition spectra, linear energy transfer spectra, and flux and dose rates for charged particles will be measured simultaneously with near real time resolution at different depths of the phantom by means of three silicon detectors. Data obtained together with data from other active and passive dosimeters will be used to estimate the radiation risk to the crewmembers, which verify the models of radiation environment in low Earth orbit. Presented are the test results of the prototype unit. Liulin-5 will be flown on the ISS in the year 2003.
Research Containing: Radiation Monitoring/*instrumentation
A passive neutron-bubble dosemeter (BD), developed by Bubble Technology Industries, has been used for space applications. Both the bubble detector-personal neutron dosemeter and bubble detector spectrometer have been studied at ground-based facilities in order to characterise their response due to neutrons, heavy ion particles and protons. This technology was first used during the Canadian-Russian collaboration aboard the Russian satellite BION-9, and subsequently on other space missions, including later BION satellites, the space transportation system, Russian MIR space station and International Space Station. This paper provides an overview of the experiments that have been performed for both ground-based and space studies in an effort to characterise the response of these detectors to various particle types in low earth orbit and presents results from the various space investigations.
Results of measuring neutron dose inside the Russian segment of the International Space Station using bubble detectors in experiment Matreshka-R
Distribution of neutron equivalent dose both inside and outside the spherical phantom (experiment Matryeshka-R) was determined with the help of dedicated research equipment "Bubble-dosimeter". Equipment is built up from an automatic bubbles counter and 8 bubble detectors of neutrons with energy ranging from approximately 200 keV to 15 MeV. Measurements inside the ISS were made in several 7-day sessions in the period from April 2006 till October 2007 (ISS increments 13-15). According to the bubble detectors on the outside of the phantom, ambient neutron dose H*(10) was equal to 0.1 mSv/d or approximately 20% of the dose from charged particles inside the ISS. In the tissue-equivalent phantom, neutron dose was 1.2 +/- 0.2 times less as compared with the phantom surface which characterized the degree of dose attenuation in cosmonaut's body.
The results are presented of measurements high-energy particles in a customary manned space station orbit (a 350–450-km altitude, a 51.6° inclination; Salyut-6 and 7, MIR). The particles were recorded by the chambers composed of the Lavsan (polyethyleneterephtalate) solid-state nuclear track detector layers mounted outside a spacecraft for 1–3 years. A high resolution has been attained in the charge and energy spectra of 30–200 MeV/n Fe group particles. The results of measuring the particle fluxes in the space station orbits are used to restore the initial particle energy spectra in terms of the models that describe the galactic and solar cosmic rays and their penetration to the Earth's magnetosphere. The analysis demonstrates a high effectiveness of the described methods when applied to quite a number of space physics problems.