Ion chamber with a flat sensitivity response characteristic

摘要

An ion chamber exhibiting a flat response to a wide range of incident gamma energy is provided by a high-pressure fill gas mixture of a first major constituent, low atomic number gas which exhibits a reduced gamma response at low gamma energy levels, and a second minor constituent, high atomic number gas which exhibits an increased gamma response at low gamma energy levels. The preferred fill gas mixture is nitrogen as the major constituent and xenon as the minor constituent.