Evaluation of a PTW diamond detector for electron beam measurements

A PTW Riga diamond detector has been evaluated for use in electron beam dosimetry, by comparing results with those obtained using a diode (Scanditronix p-Si) and an ionization chamber (Scanditronix RK). The directional response of the diamond at 6 MeV and 15 MeV is more uniform than that of the diode, but for both detectors there is a dip in response when the beam axis is perpendicular to the detector stem. Spatial resolution of the diode detector, measured beneath a 2 mm wide slit, is slightly better than that of the diamond detector with detector stems both parallel and perpendicular to the beam axis. Diamond and diode depth-dose curves both agree well with corrected ionization chamber results at 15 MeV, while at 6 MeV the diamond is in better agreement. This indicates that the diode provides better spatial resolution than the diamond for measuring profiles, but the diamond is preferable for low-energy depth-dose measurements.