A research of the X-rays energy response of ionization chamber dosimeter used in radiation therapy

The X-rays energy response of three types of ionization chamber dosimeter was researched used by the radiation beam of the primary exposure standard for medium energy X-rays (60∼250 kV). Ten instruments of every type dosimeter were calibrated, the average value and the standard deviation of energy response were obtained, and we also analyzed and evaluated the results. The energy response of two types of ionization chamber is below 4%, it is suitable for application in radiotherapy according to the verification regulation of ionization chamber dosimeters used in radiotherapy. (authors)