Dose per Pulse Monitoring of MeV Photon Beams

Modern dynamic radiotherapies in cancer treatment are oriented to release high dose values in the shortest irradiation time. For these techniques, fast detectors and dedicated conditioning electronics will play a fundamental role for beam diagnostics to verify the necessary quality assurance requirements of treatments. This work describes a measurement system based on a single-crystal synthetic diamond able to monitor the dose released by each X-ray pulse generated by a medical LINAC. A gated-integration method, performed by a specifically designed electronics, has been used to measure the charge photogenerated in diamond by each impinging X-pulse. Exploiting the synchronization signal available in a LINAC apparatus, our system allows performing pulse-beam diagnostics with an acquisition time limited to the period around each pulse. Therefore, the proposed solution represents an effective tool for real-time dosimetry in modern radiotherapy applications and assures a better accuracy in comparison to conventional electrometer-based measurement systems that require longer acquisition periods.