- Nuclear fuel contains large quantities of nuclear material, such as uranium and plutonium. According to the IAEA safeguards rules and requirements, these types material should be subject to domestic and independent international controls. The purpose of this kind of investigations is to determine the type and quantity of the nuclear materials with level of precision that it can detect the fact and extent of any theft. Accordingly, the various nuclear facilities are required to keep a record of their nuclear material balances, which may be verified at any time by staff of independent regulatory authorities (IAEA, EURATOM) in order to meet the non-proliferation objectives.
- The main objective of the doctoral research is to develop a non-destructive nuclear analytical method and calculation model for the reliable and accurate determination of the nuclear material content of spent fuel, which is independent of the methods applied by the nuclear power plant itself. One of the most suitable measurement techniques for this purpose is gamma spectrometry, which can be performed safely and relatively quickly compared to other nuclear analytical methods. It is not possible to directly measure the gamma irradiation of fissionable isotopes in spent fuel, but it is already possible to determine the gamma activity of fission products. The gamma spectrometric information obtained can be used to determine the uranium and plutonium content of spent fuel, which can be determined by calculation in the light of their irradiation history. In order to implement the computational model, it may consider the use of deterministic and Monte-Carlo based codes, taking into account the available computational accuracy and their expected runtime.
- In addition to the routine use of 134Cs and 137Cs isotopes, other fission products (106Ru, 154Eu, etc.) should be investigated to calculate fuel burnup. This is because the activity ratio of the two caesium isotopes is not independent of the fuel burn-out history, and the relatively short half-life of the 134Cs isotope limits the applicability of the method.
- To the purpose of safeguards investigations, the analytical problem outlined above is also worth analysing from a forensic perspective. In the course of such investigations, the history of the fuel elements shall be reconstructed on the basis of the results of direct nuclear spectroscopic measurements and other publicly available information. The new analytical technique outlined above would allow the detection of relevant but hidden information in criminal cases where the evidence includes a spent fuel.
Expected results: Having such a new nuclear analytical method would significantly expand the range of safeguards verification methods for domestic spent fuel and nuclear forensic analysis that are likely to be of international interest.
Requirements for the candidate:
- MSc in Physics or equivalent diploma
- professional interest in gamma spectrometry, its deterministic modelling and MC simulation,
- English language skills,
- experimental capability,
- IT and programming ability.