低レベル放射線自動計測システムに用いられる磁気浮上装置  [in Japanese] Magnetically levitating equipment used for an automatically measuring system of low level radioactive rays(DEPARTMENT OF ELECTRICAL ENGINEERING)  [in Japanese]

An Ionization chamber has some superior characters. One of them can be detected γ-rays in spite of a simple equipment. So the chamber has been widely used for monitoring air pollution by radioactivity. However, measurement of γ-rays in the atmosphere by using the ionization chamber is difficult because of its low sensitivity. We have developed the high sensitive ionization chamber for γ-rays constructed a magnetically levitating electrode without any insulating support. The developed equipment was applied the measurement of γ-rays in atmosphere. By using two those equipments, we have detected extremely small doses of γ-rays in the atmosphere and various gases.