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Muon decay constant

  1. Sep 18, 2010 #1
    muon decay constant/ muon flux

    where can i find the decay constant of a muon (the lambda which appears in):
    [URL]http://upload.wikimedia.org/math/3/f/2/3f28b1c0d4362b86a89f976d83d81070.png[/URL]

    thanks

    edit:
    oh the wiki page http://en.wikipedia.org/wiki/Exponential_decay
    gives the relationship that the decay constant is the reciprocal of the mean lifetime
    is that correct?
     
    Last edited by a moderator: Apr 25, 2017
  2. jcsd
  3. Sep 18, 2010 #2

    phyzguy

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    Typically you will find the half-life tabulated, which for the muon is about 2 microseconds. As the Wikipedia article you cited states, the decay constant is related to the half-life as follows:
    [tex]\lambda = \frac{ln(2)}{t_{1/2}}[/tex]
     
  4. Sep 18, 2010 #3
  5. Sep 18, 2010 #4

    Vanadium 50

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    Bob seems to be suggesting that positively and negatively charged muons have different lifetimes. This is not the case.
     
  6. Sep 18, 2010 #5
    i can see that the ratio is almost 1:1 for the mean lifetimes :)

    but my other question is where on earth are you supposed to obtain simple data on muon flux at different altitudes - like at the height where they are generally created and at ground level? im not looking for partial differential equations and all that, just for example the number of muons through a metre sqaured area per second at a height of 5000m and the number of muons through a metre squared per second at ground level
     
    Last edited: Sep 18, 2010
  7. Sep 18, 2010 #6
    The measurement of both positive and negative charged muon lifetimes is an important test to verify that they are equal, as required by CPT invariance. See second table on page 2 of

    http://pdg.lbl.gov/2004/listings/s004.pdf

    Bob S
     
  8. Sep 18, 2010 #7

    Vanadium 50

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    True, but irrelevant to what the OP asked. Please don't sidetrack the thread.
     
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