Experimental Verification of the Nuclear Data of Gadolinium for Neutron Capture Therapy

Abstract

We prepared the nuclear data of gadolinium, for the simulation calculation and the dose estimation in order to confirm the effectiveness of gadolinium neutron capture therapy (GdNCT), from the viewpoints of physics and engineering. Then, the experimental verifications of this nuclear data have been performed using Kyoto University Research Reactor (KUR). As a series of the verifications, the energy spectrum of the prompt gamma rays from the ¹⁵⁷Gd(n, γ) ¹⁵⁸Gd reaction was confirmed using a prompt gamma-ray analysis (PGA) system, installed at the E-3 neutron guide tube in KUR. For the discrete components of the released gamma rays, especially, the spectrum peaks at 79.5keV, 182keV and 6750keV were focused on, because these peaks have the sufficient intensities for measurement and can be easily discriminated from the other components. It was confirmed that the relative relations for the gamma-ray intensity among these peaks were agreed within the experimental uncertainties, between our prepared nuclear data and the PGA-measured data.

Keywords:

• gadolinium neutron capture therapy
• gadolinium 157
• neutron capture
• gamma-ray energy spectrum
• electron energy spectrum
• prompt gamma-ray analysis