[Radiotherapy Dosimeter Calibration for Absorbed Dose to Water Using Medical Accelerators].

A calibration service using a medical accelerator has been launched to calibrate a radiotherapy dosimeter in terms of an absorbed dose to water. The radiotherapy dosimeter calibrated by the calibration service can measure the absorbed dose to water without a beam quality conversion factor. In this paper, an overview of the calibration service for a high-energy photon beam and a high-energy electron beam was described, as well as methods of absorbed dose measurement and cross-calibration using the calibrated radiotherapy dosimeter. And the development status of a dose standard for a particle beam was reported.