Studies of recombination chambers filled with nitrogen for BNCT dosimetry

Dosimetric characterization of therapy beams for boron neutron capture therapy (BNCT) involves determination of dose components and among them the “nitrogen” dose due to protons generated by neutron capture on 14N. In this work, investigations were carried out using a graphite recombination chamber in order to determine the 14N capture, gamma, and fast neutron dose components. The separation of the dose components is based on differences in the shape of the saturation curve, depending on the LET spectrum of the investigated radiation. The measurements were performed in reference radiation fields at the Institute of Atomic Energy at Świerk and at a reactor beam of the INP Řež (the Czech Republic). The gamma component was determined with an accuracy of about 5%, while the variations in its value could be monitored with an accuracy of about 0.5%. Relative changes in the beam components (thermal/fast neutrons) could be detected on line with an accuracy of about 5%. It was shown that the chamber with tissue-equivalent cups could be used for the determination of the 14N capture dose at different depths in tissue

Improved dosimetry for BNCT by activation foils, modified thermoluminescent detectors and recombination chambers

Boron neutron capture therapy (BNCT) is an experimental therapy of selected tumours, based on a nuclear reaction initiated by the capture of thermal neutron by the 10B nucleus. After 10B had been delivered selectively to tumour cells, it can be activated by neutrons to deliver locally lethal high-LET radiation. BNCT beams are complex mixed radiation fields, because of broad neutron energy range, presence of gamma contamination and necessity of precise determination of several dose components. The paper present

Ambient dose equivalent measurements in secondary radiation fi elds at proton therapy facility CCB IFJ PAN in Krakow using recombination chambers

This work presents recombination methods used for secondary radiation measurements at the Facility for Proton Radiotherapy of Eye Cancer at the Institute for Nuclear Physics, IFJ, in Krakow (Poland). The measurements of H*(10) were performed, with REM-2 tissue equivalent chamber in two halls of cyclotrons AIC-144 and Proteus C-235 and in the corridors close to treatment rooms. The measurements were completed by determination of gamma radiation component, using a hydrogen-free recombination chamber. The results were compared with the measurements using rem meter types FHT 762 (WENDI-II) and NM2 FHT 192 gamma probe and with stationary dosimetric system