A synthetic diamond probe for both low-energy mammography X-rays and high-energy electron therapy beams

Although diamond has been studied for dosimetry principally due to its near-tissue equivalence, its use in both low-energy X-rays and high-energy electron beams has not been reported. This report is based on dosimetric studies of a synthetic diamond probe when subjected to diagnostic mammography X-ray photons and megavoltage electron therapy beams. The probe, constructed using entirely tissue-equivalent Perspex body, was configured for radiation dose measurement in either ‘edge-on’ or ‘flat-on’ exposure geometry without having first to re-orient the diamond within the body of the detector, and it was designed to be compatible with commercial electrometer systems. The radiation response of the diamond tested showed negligible energy dependence; its minimal background signal, high sensitivity (547.52 nC Gy −1 mm −3) and suitability for measurements in small radiation fields of steep dose gradients due to its small size make it suitable for clinical dosimetry. The presented probe has the potential advantage of replacing conventional radiation dosimeters. ► A tissue-equivalent synthetic diamond probe for X-rays and electron beams. ► Different exposure geometries for X-rays (‘edge-on’) and electron beams (‘flaton’). ► Linear absorbed dose response, negligible energy and minimal angular dependence. ► Probe has high sensitivity with potential to replace conventional dosimeters. ► Probe is compatible with commercially available electrometer systems.