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Half-life functions

  1. May 11, 2003 #1


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    Greetings !

    I'd like to ask a few questions about
    half-life (not the PC game :wink:) functions:

    1. Are they of the same shape for all
    nuclear particle decay reactions currently
    known and observed ?

    2. What is the function mathematicly (and
    it's relevant shape of course) ?

    3. What are the physical parameters if they
    are known (I guess not though) ?

    4. Can the shape of the function help find
    a solution to the cause of the nuclear decay
    (if there is such a thing at all) ?

    Thanks ! :smile:

    Live long and prosper.
  2. jcsd
  3. May 11, 2003 #2

    Tom Mattson

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    Do you mean N=N0e-kt?

    That is valid only for large samples, as it treats the number of radioactive species as continuous. But yes, that can be used to model large samples of any radioisotope.

    See above: Decaying exponential.

    You need to know the initial amount of radioactive species (N0). You can find the half life by measuring the amount of radioactive species at some later time.

    No, it cannot. For that you have to look at the gauge theories describing the appropriate reaction. For instance, α-decay is a strong interaction, and β-decay is a weak interaction.

    No, thank you for getting me out of the philosophy forum. I needed some air!
  4. May 11, 2003 #3
    Is it understood why an atom will decay when it does, or does it just still seem spontaneous even after someone understands quantum mechanics, standard model, etc.
  5. May 11, 2003 #4

    Tom Mattson

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    It is indeed impossible to predict when any single nucleus will decay. All we can do is predict averages over large samples.
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