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Poisson Distro.

  1. Feb 1, 2008 #1
    Why does particle emission follow a poisson?

    Thanks in advance
  2. jcsd
  3. Feb 1, 2008 #2


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    This is a vague question.

    What particle? And what property exactly that follows a poisson distribution? I can show you the energy spectrum of beta decay that follows nowhere near a poisson distribution.

    If you wish to get some degree of a rational response, you should make some effort into presenting a clear question.

  4. Feb 1, 2008 #3

    Ben Niehoff

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    He probably means that particle emission follows a Poisson process.

    If an event has a constant probability per unit time of occurring (i.e., the probability of X happening in the next 10 seconds is always a constant [itex]\lambda[/itex]), then that event can be modeled as a Poisson process. Google it to find a derivation.
  5. Feb 1, 2008 #4
    thanks a lot, sorry about the lack of detail, i was trying to type it before my laptop battery died... what i meant was what ben said. i was looking for the derivation in specific.
  6. Feb 1, 2008 #5


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    The possion distribution is derived from the binomial distribution in with two limits. i. the probablity for one event goes to zero and ii. the number of trials goes to infinty. I dont remember it 100%, so better look it up on google or in a reference in introductory statistics. And that is also why one can say (as Ben Niehoff) that the probablity is constant [itex]\lambda[/itex]
    and so on.

    The reason for WHY radioactive decay follow poisson is that is a probibalistic process, and that you have a large sample.
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