GAMMA AND ENCLOSURE DOSIMETRY FOR TL ESR DATING WITH THE NEW AL2O3-C TL DOSIMETER/

Al2O3:C manufactured by LAIKS-CORUND, Ekaterineburg, Russia, offers se veral advantages for the measurement of environmental radiation; stabi lity, low self-dose, high sensitivity and energy deposition features u nder gamma and beta irradiation very similar to quartz and quartz-like TL minerals. In the present work those properties were tested for in situ gamma dosimetry, by comparison with other dosimetric techniques. It was confirmed that this phosphor is very well adapted to this purpo se. On the other hand, the new alumina can be made insensitive to exte rnal alpha radiation by means of thermal treatments. This alpha-insens itized alumina is very interesting for enclosure dosimetry in the pers pective of quartz inclusion dating. In this technique, the quartz grai ns to be dated are faithfully simulated by alumina: the phosphor allow s us to measure directly the dose that would be experienced by quartz grains (HF etched, as usual). However, because the attenuation of beta radiation by coarse grains must be taken into account in inclusion da ting, the role of this factor was theoretically and experimentally-wit h Al2O3-explored. The preliminary experiments indicated that enclosure dosimetry with this new alumina was a promising technique.