Concept of a BNCT line with in-pool fission converter at MARIA reactor in Swierk

Abstract

BNCT facility in the Institute of Atomic Energy in Otwock-Swierk is under construction at the horizontal channel H2 of the research reactor MARIA. Measurements of the neutron energy spectrum performed at the front of the H2 experimental channel, have shown that flux of epithermal neutrons (above 10 keV) at the BNCT irradiation port was below 10 9 n cm 2 s 1 i.e. it was too low to be directly used for the BNCT treatment. Therefore, a fission converter will be placed between the reactor core and the periphery of the graphite reflector of MARIA reactor. The uranium converter will be powered by the densely packed EK-10 fuel elements with 10% enrichment. Preliminary calculations have shown that the total neutron flux in the converter will be about 10 13 n cm 2 s 1 and flux of epithermal neutrons at the entrance to the filter/moderator of the beam will be about 2•10 9 n cm 2 s 1 .

Summary of recent BNCT Polish programme and future plans

“…6 (Pytel et al, 2009). It was planned to use the same unemployed H2 horizontal channel to deliver the neutron beam outside the pool, from the converter to the irradiation room.…”

“…Test were performed by pumping method. Detailed calculations of neutron, heat transfer and flow analyses in steady state and transient, the activity of fission products and the radiological risk of gamma radiation emitted are included in the internal NCBJ document called "Safety Analyses of BNCT converter" (Pytel et al, 2009). In order to determine the heat generation in the fuel EK-10, the calculations of the reactor core with neutron converter were done using WIMS-ANL/REBUS codes (J.…”

MARIA Reactor Irradiation Technology Capabilities towards Advanced Applications

“…The newly reconstructed H2 channel will supply a new radiobiological research facility with the neutron beam of epithermal energies. It will be primarily dedicated to boron neutron capture therapy (BNCT) research [28,29]. The epithermal energies are achieved by the means of a uranium based neutron converter.…”