Embedded Files
Our secondary mission consists of two parts, of which the Geiger Müller tube is one. Now, before we go into our version of it, we should all understand the basic principles behind the tube. The tube is built of two parts, the anode (i.e. a central wire in the middle of the tube) and the cathode (a metal casing or wire around the anode) with an gaseous mixture in between. This all is tied together with a strong electrical voltage between the anode and the cathode.
When a radioactive particle enters the tube and ionizes one of the gas molecules it starts a chain reaction called a Townsend avalanche. The strong voltage difference accelerates the now free electron towards the anode, and on its way there it collides with other gas molecules, releasing even more electrons. This is how we can detect these radioactive particles even when there are so few of them! When these electrons finally reach the anode, it results in a current we can measure.
All this is then hooked up to a counter that records any current that flows trough the system.
GM-tube and counter,
Our version will be bare bones, but nevertheless working GM-tube. The cathode is an aluminum tube cut to size with a metal wire running through. Our first version of the tube would have been just this with end caps made of heat-shrink plastic and a small valve to fill it with argon.
Our current plan for the GM-tube, is a glass container
Page updated
Report abuse