Time Resolved Photoluminescence From a Phosphate Glass (Gd-300) Irradiated With Heavy Ions and Gamma Rays

Abstract

The time-resolved photoluminescence from a phosphate-glass photoluminescence dosimeter (GD-300) was compared for different quality radiations: relativistic heavy ions (12C and 40Ar) and 60Co gamma rays. The intensities of photoluminescence afterglow at 2-7 micro(s) after pulsed UV excitation, i.e., in the time range used for conventional dosimetry, soon reached stable conditions for all radiations. Whereas the early photoluminescence emission at the range less than 0.4 micro(s) was notably unstable for gamma rays only; it continued decreasing even at 2 d after irradiation. In contrast, the photoluminescence afterglows for the heavy ions were stable over the whole range after excitation. These results indicate that the process of photoluminescence-center formation is different for heavy ions and gamma rays.

Changes in Optical Transmission Caused by Gamma Ray Induced Coloring in Photoluminescence Dosimeter

“…3, time-resolved PL emissions are shown as averages of 30 readouts; background signals were negligibly small in all cases. The curves of PL afterglow showed similar shapes despite the dose levels; changes in the curve shapes as seen for heavy ion irradiation (Yasuda and Ishidoya 2003) were not observed for high dose gamma rays. The PL intensities, however, showed non-linear responses to gamma-ray doses.…”

“…Also, it is desirable to investigate reasons why PLDs show low efficiencies for heavy charged, high-LET particles Fujitaka 2000, 2002;Yasuda and Ishidoya 2003), compared to thermoluminescence dosimeters (Yasuda 2001(Yasuda , 2002. Such a peculiar feature of PLDs may relate to coloring that should happen in a small-scale densely-ionized region along the track of a particle.…”

Radiation Safety

“…Because the personnel monitoring is to measure and confirm individually the personal dose, badge types are employed to equip on radiation workers. Now, OSLs (Optical Stimulate Luminescence, TLDs (Thermo Luminescence Detectors), film badges (13), and Glass dosimeters (14), etc are used to measure theγ(X)ray dose. For a dose due to high energy neutrons, CR-39 neutron track detectors are employed, mainly.…”

Chemical and physical characteristics of self-fabricated radiophotoluminescent glass dosimeter

“…In contrast, the readout process does not eliminate the luminescent centers in radiophotoluminescent glass dosimeters (RPLGDs), the RPLGDs could be read repeatedly. The RPLGD was first applied in radiation measurement by Schulman in 1951 (Yasuda and Ishidoya, 2003;Asahi Techno Glass Corporation, 2004). The Schulman's selffabricated RPLGD consisted of 25% of KPO 3 , 25% of Ba(PO 3 ) 2 , 50% of Al(PO 3 ) 2 and appropriate amounts of AgPO 3 .…”