Experimental study on the performance of an epithermal neutron flux monitor for BNCT

Techniques to Measure Absolute Neutron Spectrum and Intensity for Accelerator Based Neutron Source for BNCT

“…The activity of 72 Ga was measured after the irradiation and compared with the calculation result to discuss the validity of the monitor. As a result, the agreement was acceptable to show that the monitor would be utilized in real scenes of ABNS-BNCT [10].…”

“…Boron Neutron Capture Therapy (BNCT) is known to be a new cancer treatment for the next generation. Administering 10 B including compound, 10 B is accumulated in tumor cells. Neutrons are then irradiated from outside of a human body to induce a neutron-10 B reaction, n + 10 B → α + 7 Li.…”

“…This is more-or-less the same as the size of a human body cell. As a result, if 10 B is accumulated only in tumor cells, only the tumor cells can be killed. BNCT can be regarded as a cell selective cancer therapy with charged particles.…”

The new design and validation of an epithermal neutron flux detector using 71Ga(n,γ)72Ga reaction for BNCT

“…Because of the intense epithermal neutron flux of the BNCT neutron beam, that is, not less than 1 × 10 9 n/cm 2 /s, the activation detector is more suitable than the active detector for characterizing the field of the BNCT neutron beam [1]. Thus, two types of activation neutron flux detectors, i.e., the epithermal neutron flux detector [2][3][4][5][6] and the neutron flux detectors from 20 keV to 1 MeV [4,[7][8][9], using 71 Ga(n, γ) 72 Ga reaction have been developed by the authors' group for determining the epithermal neutron flux and the neutron flux from 20 keV to 1 MeV of the BNCT neutron beam. These detectors are designed to be spherical to minimize the effect of neutron incidence direction dependence.…”

The neutron flux monitors from 20 keV to 1 MeV for BNCT: performance study using accelerator-based neutron sources

“…However, fast neutrons from 20 keV to 1 MeV still remain and they are difficult to completely remove. Such fast neutrons have larger relative biological effectiveness [1], therefore, in order to estimate the unwanted invasive radiation dose to treated patients and improve the measurement accuracy of the epithermal neutron flux monitor developed for BNCT [2][3][4][5][6], two monitors with gallium nitride (GaN) wafers as activation material have been developed using Monte Carlo simulations to predict the neutron fluxes from 20 keV to 1 MeV for ABNSs [4,7,8]. The schematic views of the neutron flux monitors from 20 keV to 1 MeV (named monitor 1 and monitor 2) are shown in figure 1.…”