I did a course on Nuclear Physics last year. This page seems to be saved in my favourites from when I was doing the assignment.
http://hyperphysics....ructcon.html#c1I remember it was quite good, but then again that was for a uni project, so It may not be all that great for you. Geiger-Muller counters aren't exactly the best way of measuring ratiation. Well, they may be the best way, but theres a few problems with them that you should take into account. The tubes have a "paralytic time' of about 50-200 microseconds, meaning that after counting a disintergration, the tube cannot register a second one until the paralytic time is up. Hence, high radiation sources aren't going to measure correctly. Also take into account that alpha particles only travel a few centimetres in air, and as such a lot of readings may not actually reach your counter. Also, beta particles traveling away from the detector can bounce back and register extra counts(this is called back-scattering). Another important thing to note is that radioactive decay by definition is random. As such, you will need to conduct a statistical analysis to check that fluctuations are in fact random. If you have any questions, feel free to ask, though the internet isn't the best medium for quick responses.
Edit: You can guess who handed in a lab report yesterday on Geiger-Muller Counters
This post has been edited by SimeSublime: 10 September 2004 - 10:16 AM
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