The applicant shall possess sufficient knowledge and experience in the field of nuclear techniques, especially radiation protection and dosimetry. He/she shall be able to work also independently, has new ideas and his/her English is sufficient for performing literature survey in the field.
Contaminations and selectivity of silicon detector charged particle detectors for space weather and space dosimetry measurements
Fizikai Tudományok Doktori Iskola
MTA Centre for Energy Research
29-33 Konkoly Thege Miklós út, H-1121 Budapest, Hungary
The space radiation in orbit may considerably vary with time and from one location to the other in the Earth’s magnetosphere. Monitoring the changes in the space weather and conducting space radiation measurements in orbit are, therefore, particularly important. By having more detailed data, the uncertainties in the existing space radiation models can be improved. Several types of detector systems have been developed or under development in the Space Dosimetry Research Group at the Centre for Energy Research, Hungarian Academy of Sciences to measure different components of space radiation. The TRITEL three-dimensional silicon detector system is dedicated for space dosimetry and measurement of the linear energy transfer (LET) spectrum of charged particles, whereas the RADTEL telescope of the RadMag space weather instrument will measure the energy spectra of protons, electrons and heavier ions for space weather purposes.
Candidate will evaluate the effects of cross-contaminations in the different types of energy deposition spectra in the case of different shielding configurations by means of Monte Carlo calculations. For that, Candidate will be familiarized with and learn the use of the Geant4 Radiation Analysis for Space (GRAS) Monte Carlo tool developed and used by the European Space Agency and based on the Geant 4 toolkit for the simulation of the passage of particles through matter developed in the European Organization for Nuclear Research (CERN). Candidate will model TRITEL and RADTEL geometries in different shielding configurations and perform sensitivity analysis on the results. Candidate shall recommend simple silicon detector geometries to be used for ground measurements with protons, heavy ions, and possibly electrons and define the measurement setup and parameters of the measurements. The Candidate shall use those data for validation of the simulations performed. Candidate shall select the physics models to be used and, if necessary, perform cross-comparison with calculations performed with other radiation transport tools, e.g. FLUKA. Candidate will define optimal telescope geometries for different orbits by performing Monte Carlo simulations and using realistic primary spectra based on estimations using standard space radiation models recommended by the European Cooperation for Space Standardization (ECSS). Candidate will recommend and elaborate techniques for reducing contaminations in the measurement data to improve performance of the detector systems. Algorithms will be also developed to make possible corrections for cross-contamination of data; uncertainties will be also estimated.