Radiation hardness of polycrystalline ceramic scintillators for radioisotope batteries

Abstract

The usefulness of GYGAG(Ce) transparent polycrystalline ceramic garnet scintillators as the conversion medium in alpha and beta-fueled radioisotope batteries was explored through 0.5 to 3.5 MeV helium ion, alpha, and 0.5-2 MeV electron irradiations. Absorption spectra and light yields were measured before and after irradiations. Within experimental error no degradation in light yield was observed for the electron-irradiated samples as measured via beta or gamma excitation. A small increase in optical absorption near the emission wavelength was observed following the largest dose electron irradiation. Significant reduction in light yield was observed following helium ion irradiation. Partial recovery of the light yield was observed following annealing in oxygen above 400oC for helium ion irradiated samples. These results suggest that GYGAG(Ce) may prove useful for beta-fueled scintillation-based radioisotope batteries by allowing for higher energy beta emitters, increased power densities, and long service lifetimes.

Compositional regulation of multi-component GYGAG:Ce scintillation ceramics: Self-sintering-aid effect and afterglow suppression

“…To meet the needs of advanced nuclear medical imaging devices and high-energy physics, scintillators with higher performance are urgently required [1][2][3][4][5]. Multicomponent garnets with the chemical composition of (Gd,Lu,Y) 3 (Ga,Al,Y) 5 O 12 have attracted wide attention because of their high stopping power, high light yield (LY), fast scintillation decay, and strong radiation stability [6][7][8][9]. It should be noted that due to the flexibility of ion substitution in the garnet lattice, these physicochemical properties and scintillation performance are tunable through component design [10][11][12][13][14].…”