1995 Volume 44 Issue 9 Pages 603-607
Alanine/electron spin resonance (ESR) dosimetry has excellent characteristics such as wide measurable range, stability after irradiation, and high precision. Different types of dosimeter and easy-handling readout systems have been developed, mainly for dosimetry of process control in radiation processing over high dose range from 100 Gy to 100 kGy. Alanine dosimeter consisted of tissue-equivalent material is expected to be also useful in radiotherapy dosimetry at doses below 100 Gy.
In this paper, for application of alanine polystyrene (PS) dosimeters to low dose range below 100 Gy, 18 MV X-rays and 6-20 MeV electron beams were used to study on zero-dose response of unirradiated dosimeters, feasibility to subtract zero-dose response from dose response of irradiated ones, dose estimation to normalize dose response to that at 1 kGy, and uncertainty in dose estimation procedure.
Álanine-PS dosimeters have already enough potential to measure doses higher than 10 Gy within precision of ±3%, although further improvement in sample preparation and ESR signal intensity manipulation procedure are necessary to reduce zero-dose response and to get higher signal/noise ratio.
