MEASUREMENTS OF THE BRAGG PEAK DEPTH BY A PPC-40 IONIZATION CHAMBER AND A DIGITAL IMAGING DETECTOR

Abstract

Experimental measurements of the Bragg peak depth by two methods: the air ionization chamber and the digital imaging detector (DIDE) for proton energies of 50, 100, and 170 MeV are compared. The principle of operation of a new detector type, i.e., the DIDE for measuring the energy release region of the proton beam passing through a water phantom is considered. The DIDE detector is a coordinate meter of the Bragg peak depth profile which, using a known energy dependence of the dose, i.e., “quality curve,” can recalculate the coordinate to the doze depth profile (with controlled accelerator output stability). It is indicated that the binning (pixel summing) mode is most important for light collection from radioluminescence. In measuring the coordinate region of energy release (Bragg peak) by the detector, the result appears almost instantaneously and with an accuracy regulated by the IAEA.