An ionization chamber is a device composed of a cylinder containing a gas, such as nitrogen, argon, or a gas mixture, under a given pressure. This cylinder is equipped with electrodes that collect electrical charges. These chambers are used in radiography to provide higher resolution images and reduce the radiation dose required. They are also used in tracking detectors, such as the 16,000 Micro Strip gas chambers used in the CMS detector, to measure the fingerprints of charged particles with an accuracy of one hundredth of a millimeter.
The gas used in an ionization chamber can be nitrogen, argon, or a mixture of both. In some cases, dimethyl ether is also added to the mixture. The readings of air-filled ionization chambers are influenced by magnetic fields. To reduce this effect, the chamber can be filled with a gas mixture instead of air.
The construction and characteristics of the cylindrical ion pulse ionization chamber (CIPIC) with a working volume of 3.2 L have been described. This chamber consists of a gas-permeable silicone structure that allows the transfer of gas to the chamber. Simulation of the interaction of X-rays with a gas in an ionization chamber by the Monte Carlo method has also been reported. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at higher temperatures; a hydride heating means for selectively heating the metal hydride to temperatures sufficiently high to release hydrogen gas from the metal hydride; and dampers positioned between the metal hydride and the chamber to selectively allow hydrogen to flow or not to flow between said metal hydride and said chamber.
A 14-liter spherical ionization chamber has been developed for accurate measurement of ambient radiation dose rate. A three-electrode ionization chamber for gamma-ray dosimetry of fission product activity has also been designed and developed. The hybrid spark chamber allowed us to obtain a good counting plateau by configuring the gas multiplication in the proportional space of the chamber moderately high. The reduced dispersion material in the chamber gas and in the inner liner separating the drift chamber from the silicon vertex detector provides a reduction of the multiple dispersion component of the moment resolution and an extension of the usable measurement length in the silicon. The size of the test chamber can be mechanically adjusted by the use of novel bellows to reduce and optimize the amount of gas space in a test chamber surrounding the hermetically sealed object under test.
A waste gas analyzer (RGA) was connected to the cryostat chamber to study the behavior of the main gases within this chamber with temperature. In conclusion, nitrogen, argon, or a mixture of both are typically used as gases in an ionization chamber. In some cases, dimethyl ether is also added to this mixture. The readings of air-filled ionization chambers are influenced by magnetic fields, so it is recommended to fill them with a gas mixture instead of air.
