Tenebrescence has been reported to have a high potential for personal ultraviolet (UV) detection. Color changes can detect UV doses and can also be used as visual sensors for X-rays. Hackmanite is known to exhibit tenebrescence. This study investigated the kinetics of electron-trapping levels contributing to the luminescence of Na8Al6Si6O24(Cl,S)2 hackmanite using thermoluminescence. The glow curves were measured at a heating rate of 5 K/s on hackmanite irradiated with X-rays. The physical parameters of the electron-trapping levels were evaluated by analyzing them using the deconvolution, peak shape, and initial rise methods. The Na8Al6Si6O24(Cl,S)2 hackmanite had at least five trapping levels, with activation energies of 0.78, 1.12, 1.86, 1.26, and 1.18 eV and corresponding peak trap lifetimes of 3.59, 2.71, 1.47, 3.34, and 3.91 s, respectively. The estimated migration time was 15.0 s.
Keywords: F-center; activation energy; hackmanite; tenebrescence; thermoluminescence.