Thermoluminescence behavior of magnesium oxide exposed to gamma and ultraviolet radiations

Abstract

Magnesium oxide (MgO) has been investigated as a possible candidate for gamma (γ) dosimetry. One thermoluminescence (TL) peak was observed in the red emission band around 372 °C in the pristine sample. The glow curves indicate that the main TL peaks appear at nearly the same temperatures after γ and ultraviolet irradiations. The dose response has a linear behavior at intermediate dose levels 1–100 Gy, and then becomes sublinear at high dose levels 0.5–50 kGy. The dose dependence of the phototransfer TL signal is recorded in the γ dose range from 0.05 to 50 Gy. Fading studies over a period of 75 days show that the γ-irradiated aliquots faded by 32% when exposed to 1 Gy. Comparison of the results from the present work with those found in the literature shows that differences are sample- and instrument-dependent. The results further predict the potential of MgO as a phosphor in accident and industrial dosimetry taking into consideration the fading effects.

Keywords:

• thermoluminescence
• gamma
• ultraviolet irradiations
• dose response
• fading