The Beta stopper is an ingenious idea from our friends at CLEAPSS
The Beta stopper is an aluminium cylinder made to fit over a standard 14mm diameter Radium source
The source is inserted in a hollow and secured in place with a nylon screw
The Aluminium is thick enough to block all of the alpha and beta emissions, allowing only the gamma radiation through
The Beta stopper is a very inexpensive alternative to buying a new Co‐60 source and gives great results when used for the gamma radiation inverse square law experiment
