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Gaseous ionization detectors are radiation detection instruments used in particle physics to detect the presence of ionising particles, and in radiation protection applications to measure ionizing radiation. They use the ionising effect of radiation upon a gas-filled sensor. If a particle has enough energy to ionize a gas atom or molecule, the resulting electrons and ions cause a current flow which can be measured. Gaseous ionisation detectors form an important group of instruments used for radiation detection and measurement. This article gives a quick overview of the principal types, and more detailed information can be found in the articles on each instrument. The accompanying plot shows the variation of ion pair generation with varying applied voltage for constant incident radiation. There are three main practical operating regions, one of which each type utilises. ==Types== The three basic types of gaseous ionization detectors are: *ionization chambers *proportional counters *Geiger-Müller tubes All of these have the same basic design of two electrodes separated by air or a special fill gas, but each uses a different method to measure the total number of ion-pairs that are collected.〔McGregor, Douglas S. "Chapter 8 - Detection and Measurement of Radiation." Fundamentals of Nuclear Science and Engineering, Second Edition. By J. Kenneth Shultis and Richard E. Faw. 2nd ed. CRC, 2007. 202-222. Print.〕 The strength of the electric field between the electrodes and the type and pressure of the fill gas determines the detector's response to ionizing radiation. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Gaseous ionization detectors」の詳細全文を読む スポンサード リンク
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