Annual report - 2008
DOBIES :
Dosimetry for Biological Experiments in Space
The objective of this project is to develop a standard dosimetric method (as a combination of different techniques) to measure onboard a spacecraft accurately the absorbed doses and equivalent doses in biological samples. Knowledge of the absorbed doses and equivalent doses is very important for a good understanding of the observed behavior of biological samples in space. Together with the microgravity condition, the cosmic radiation is a very important factor contributing to the different behavior of biological samples in space compared to earth conditions.
A measurement and calculation procedure for such measurements is to be developed and a standard measurement kit will be made for different biological and microbiological samples (in vitro cells, tissue, bone,), different packaging materials and different positions in a spacecraft. A special case would be the dosimetry of samples that are located in external modules, like the EXPOSE hardware.
This objective can be achieved by studies of the LET dependencies of the different types of detectors. This requires irradiations in standard high energy particle fields on earth. By measuring the LET spectra during some space flights, the influence of different locations and packaging materials can be assessed. Knowing the LET spectra and the responses of the different types of detectors, the doses can be calculated for different sample materials and geometries. The results of the real dosimetric experiments during different flights will lead to an optimization of the methodology and calculations tested.
In conclusion, the DOBIES experiments will study the responses of different detector types in real and simulated space radiation fields. This will lead to a unique recommendation and description on dosimetric systems for radiobiological experiments in space.
DESCRIPTION OF WORK PERFORMED
Different types of dosimeters are used:
- Thermoluminescent (TL) detectors of different composition;
- Two different types of optically stimulated (OSL) detectors (Al2O3:C); and
- Track etch detectors (American Technical Plastics CR-39 and Page CR-39).
While first two type of detectors are used for low LET, the last one mostly for high LET component of complex space radiation field. The combination of both types of detectors will allow better characterisation of it. Research on the responses of these different detectors is needed to be able to correct for the specific radiation field in space. Therefore ground based experiments are necessary as well as for space irradiations. Ground based experiments have been realised:
1. In photon radiation reference beam; a good agreement for OSL, and TLD detector of three laboratories (SCK/CEN, OSU, NPI) has been observed.
2. Different ground reference experiments have been (or will be) performed to simulate the radiation flux found in space (in terms of spectral shape) with the aid of accelerators or reactors:
a) Ground based tests have included characterising response of TLD’s, OSLD’s and track etch detectors to neutrons, , Belgium in November 2006. Here mono-energetic neutron beams available at the JRC-IRMM in Geel at were used.. These experiment was just repeated and extended with higher neutron doses and other neutron energies with new irradiations in November 2006 and/or 2007.
b) Irradiations have also been done at the iThemba laboratory (Cape Town) where high energy neutrons (100 MeV and 200 MeV) have been used to irradiate the DOBIES detectors.
c) At the CERF field (CERN, Switzerland) we were able to simulate with accelerators the neutron spectrum encountered in the space at the level of the ISS. In total, three exposures have been performed at CERN and treated during DOBIES program, i.e. between 2006 and 2008 years.
d) Several series of irradiation at heavy ion beams (accelerators HIMAC, NSRL, LUML, Dubna) have been performed and analysed during 2006 to 2008 years, beams of ions (from He to Ar, with LET 2 to 600 keV?m) were used.
e) Particular irradiations have been done at Dubna, Russia in 2007. Here proton beams were used to characterise our detectors, at the entrance and in Bragg peak region. These results obtained permitted better to understand the importance of secondary protons in space radiation fields.
All results mentioned have been analysed, discussed and partly already published.
During the period of DOBIES project, team and its members participated by using TLD, OSL, and TED at several space flights space flights:
1) The flight with BASE-A biological experiments (October 2006). The differences between the responses of the different detectors were analysed and prepared for publication.
2) Space experiment MATROSKA, MTR III, together with SPD experiments. The were realised April _ October 2007, the results have been analysed and partialy published.
3) Space intercomparison SI 2, in which in total 12 laboratories have been participated. It was also realised between April and October 2007. The publication of results will be performed when all results are available.
4) The flights with BASE-B/C biological experiments (October 2008). The differences between the responses of the different detectors are now analysed.
REPORTS
Jadrníčková, I., Spurný, F.: Dosimetry and microdosimetry onboard International Space Station for Radiobiology; Experiment BASE A, program DOBIES. Report DRD NPI AS CR 578/07, Prague January 2007
Spurný, F., Jadrníčková, I., Vanhavere, F. etal. (2008) Comparison of different Tors, OSLs and track etch detectors (TED) in high energy proton beam; program DOBIES. Report DRD NPI AS CR 598/08, Prague April 2008
Jadrníčková, I., Yasuda, N., Uchihori, Y., Shurshakov, V., Spurný, F. etal. (2008) Inter Comparison of the Radiation Doses Obtained by Various Passive Detectors Exposed at the Low Near-Earth Orbits during Phase I of the MATROSHKA-R Experiment. (IBMP-NIRS-003) Report, June, 42 page
Spurný, F., Brabcová, K., Jadrníčková, I. Shurshakov V. (2008) Dosimetry characteristics of radiation fields onboard the ISS; December2005 - September 2006: Experiment MATROSHKA III.–Report DRD NPI AS CR 600/08, Prague, April 2008
Spurný, F., Brabcová, K., Jadrníčková, I. (2008) Response of LET spectrometer based on rack etching at some neutron sources Report DRD NPI AS CR 601/08, Prague, April 2008
Spurný, F., Brabcová, K., Jadrníčková, I. (2008) Response of LET spectrometer based on track etching at some neutron sources – full analysis. Report DRD NPI AS CR 602/08, Prague, May 2008
CONTRIBUTION ON SCIENTIFIC MEETINGS
Goosens, O., Vanhavere, F., Leys, N., O’Sullivan, D., Spurny, F., Yukihara, E. and McKeever, S. Dosimetry for microbial experiment in the Space station using different track-etch and luminescent detectors. (presentation at the Workshop on Radiation Monitoring on the ISS 11 (WRMISS 11), Oxford, 2006
Participation to ESA IWG: Noordwijk: May 2007: Presentation by F. Vanhavere on the DOBIES
Jadrníčková, I., Spurný, F. Dosimetry and microdosimetry onboard International Space Station for Radiobiology; Experiment BASE A, program DOBIES. DOBIES meeting, Mol, Belgium, March 2007
Vanhavere, F., Genicot, J.L., O’Sullivan, D., Zhou, D., Spurny, F., Jadrníčková, I., Sawakuchi, G. O, and Yukihara, E. G. Dosimetry of Biological Experiments in Space (DOBIES) with Luminescence (OSL and TL) and Track Etch Detectors. Poster presentations at Solid State Dosimetry Conference 15, Delft, July 2007
Jadrníčková, I., Spurný, F., Dachev, C., and Ploc O. Upgrading of some instrumentation devoted to increase space radiation environment understanding AOGS 2007, Bangkok, July–August 2007
Spurný, F., Vanhavere, F, Further achievements in space- and aircraft exposure studies and related topics. XXIX. DRO, Dlouhé Stráně, November 2007
Jadrníčková, I., Spurný, F., Shurshakov V.A. Oboard spacecraft phantom measurements with thermoluminescent and track-etch detectors. XXIX. DRO, Dlouhé Stráně, November 2007
Kodaira, S.,Yasuda, N., Jadrníčková, I., Spurný, F. Variation of dose quantities from CR-39 detectors onboard ISS Russian segment: etching and angular correction.
Spurný, F., Brabcová, K., Jadrníčková, I., Uchihori, Y., Yasuda, N. Fragmentations as seen in C 290MeV/u, and Ne 400 MeV/u HIMAC ion beams by MDU-Liulin energy deposition spectrometer. WRMISS 13, Krakow 2008
Spurný, F., Jadrníčková I., Vanhavere, F., Brabcová, K. Neutron dosimetry and microdosimetry with track etch based LET spectrometer. 21.-23. – IRPA 12, Buenos Aires, October 19-24, 2008
PUBLICATIONS
Spurný, F., Ploc, O. and Datchev, Ts. (2007) To the neutron contribution to the exposure evel onboard International Space Station. Radiat. Prot. Dosim., 125(1-4), 519-523,
Spurný F. Jadrníčková, I., 2007. Dependence of relative thermoluminescent detectors response on the linear energy transfer. Radiat.Meas/ .Doi.10.1016/j.radmeas.2007.11.04
Jadrníčková, I., Spurný, F., 2007. LET spectrometry with track etch detectors – principles and use. Radiat.Meas. .RM 3346, accepted for publication
Vanhavere, F., Spurný, F. etal. Characterising passive dosemeters for Dosimetry of Biological experiments in Space (DOBIES). 14.-17. - COSPAR 37, Montreal, July 2008, submitted to Radiation Measurements
Spurný F. Jadrníčková, I. . (2008) Dependence of relative thermoluminescent detectors response on the linear energy transfer. Radiat.Meas/ .Doi.10.1016/j.radmeas.2007.11.04
Jadrníčková, I., Spurný, F. (2008) LET spectrometry with track etch detectors - use in high-energy radiation fields Radiat Measur. 43/2-6, 683-687
Vanhavere, F., Spurny, F., Jadrníčková, I., etal., (2008). Dosimetry of Biological Experiments in Space (DOBIES) with Luminescence (OSL and TL) and Track Etch Detectors .Meas. Rad.Measur. 43, 694-697
Spurny, F. and Dachev, T. P. (2008) New results on radiation effects on human health. Acta Geographica 57, 125-140
czechspace.cz
