Synthesis and characterization of borate glasses for thermal neutron scintillation and imaging

Abstract With the aim of finding promising neutron scintillators, different compositions have been synthesized in the glassy phase and subsequently characterized for their performance as the scintillation screen of thermal neutron imaging systems. Three new compositions having Li, B, and Gd as principal constituents, doped with Eu have been synthesized by the melt quenching method and investigated the first time for neutron imaging in the present study. The concentration of luminescent activator, Eu3+ has been optimized by performing X-ray induced emission of these glass samples. Beam purity investigation along with the luminescence ability of the commercial screen have been also performed prior to the thorough evaluation of the thermal neutron scintillation characteristics of the compositions. The glass samples have been exposed to thermal neutrons for 5 and 10 min separately at the beam port of the research reactor for their performances in conventional direct film neutron radiography technique. The glasses containing Gd have been found to have higher light yield due to energy transfer from Gd ions to Eu activators. However, the composition of 60Li2O3:10Y2O3:28.5B2O3:1.5Eu2O3 (mol%) has been observed to have low light but good thermal neutron discrimination property from the gamma background despite having lesser X-ray luminescence among all three.