Development of a Portable α-Ray Counter for Promoting Correct Understanding about Radiation

To promote correct understanding about radiation, radiation counters are now widely used for educational purposes. A radiation counter which detects α-rays and β-rays respectively, has been developed and is available commercially, but there is no portable counter for educational use which detects α-rays. People in general are very concerned about plutonium because of its toxicity and possible use in nuclear weapons. In this regard, we have developed a portable α-ray counter in order to demonstrate the nature of a-emitting radionuclides such as Pu-239. We use a Si surface barrier type semiconductor as a detector, and the total system is compact and light in weight, easily handled and inexpensive. Four kinds of samples which exist around us are prepared.