An ionization chamber is a type of gas-filled radiation detector that is widely used for detection and measurement purposes. It works by using a principle of operation that involves the ionization of gas molecules in the chamber. This ionization is caused by radiation, which then produces an electrical current that can be measured. There are several types of ionization chambers, each with its own construction and purpose.
The most common use of an ionization chamber is for dosimetry, which is the measurement of absorbed dose in radiation beams from X-ray generators and cobalt 60 sources. To ensure accuracy, calibration of the chamber must be done regularly. High-pressure xenon ionization (HPXe) chambers are ideal for use in uncontrolled environments since they have a consistent response over a wide range of temperatures. A consistent formalism can be used to determine the reference air kerma from the energy deposition in a primary standard cavity ionization chamber.
This work has been developed for the Laguna Verde Nuclear Power Plant to obtain the voltage plateau, sensitivity graph, and operating voltage of three types of ionization chambers used in its process radiation monitoring systems. Radiation monitoring in a synchrotron light source installation can also be done using magnetically levitated electrode ionization chambers. Ionization chambers can also be used to monitor the radiation output of particle accelerators with greater precision. They are also used in pediatric X-ray equipment with thermoluminescent dosimeters and cylindrical ionization chambers to measure performance curves.
The wide range of reference air kerma rates of brachytherapy sources requires the use of large volume ionization chambers. When using such ionization chambers, the ion recombination correction factor k sat must be determined. An ionization chamber can also be used with a circuit to monitor radiation output with greater precision. CT dosimetry is performed with a pencil-type ionization chamber with a sensitive volume length of 10 cm. In addition, a high-resolution position-sensitive ionization chamber has been developed and built for use in studies involving rapid ionization waveforms produced in large volume discharge chambers.
The calculated absorbed water dose for therapy ionization chambers can be used as a reference for future calibration of beam output in radiation therapy dosimetry.
