Recent content by Chrispy92

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    Graduate Estimating the order of magnitude of a ratio of two cross sections

    Cheers for the reply but that's not really what I was asking. I'm really just looking for HOW an estimate can be made with the information I've been given. It might be too specific a question but I might as well try.
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    Graduate Estimating the order of magnitude of a ratio of two cross sections

    The question is "Make a simple estimate of the order of magnitude of the ratio of the cross sections (electron,positron->2photons) and (electron,positron->3photons)" Now I know that cross section is proportional to (1/q^4)*(Phase space factor)*(Coupling constant) where q^2 = E^2 - p^2. We are...