Thermoluminescent properties of Tb3+-doped B2O3–Na2O–CaO–P2O5 glasses for neutron detection

Abstract

We fabricated Tb3+-doped B2O3–Na2O–CaO–P2O5 glasses using 10B- or 11B-enriched raw materials to develop new thermoluminescent (TL) glass materials for neutron detection. We investigated TL properties of the glass materials after X-ray and thermal neutron irradiation. A TL glow peak was observed at 376 K after X-ray irradiation, and the integrated TL intensities of the 10B- and 11B-enriched glasses were similar. This result indicates that the 10B- and 11B-enriched glasses had similar sensitivities to X-rays. A broad peak was observed in the 350–650 K range for the 10B- and 11B-enriched glasses after neutron irradiation, and the 10B-enriched glass exhibited higher TL intensities than the 11B-enriched glass in the neutron fluence range of 1.0 × 105–1.0 × 1011 neutron cm−2. This result indicates that γ-rays and high-energy particles in the 10B(n, α)7Li reaction efficiently induced thermoluminescence in the 10B-enriched glass. The TL intensity derived from the 10B(n, α)7Li reaction linearly increased with the thermal neutron fluence in the neutron fluence range of 1.0 × 105–1.0 × 1011 neutron cm−2. The 10B- and 11B-enriched glasses exhibited a wider dynamic range and lower minimum detectable neutron fluence than quite a few TL materials for neutron detection. Therefore, TL glass materials for neutron detection were successfully developed.