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Homework Help: Neutrino Annihilation

  1. Apr 26, 2010 #1
    1. The problem statement, all variables and given/known data

    Is the following process a valid interaction?

    [tex]\nu_\mu \bar{\nu}_e \rightarrow e^+ \mu[/tex]

    2. Relevant equations

    none

    3. The attempt at a solution

    I'm not sure whether lepton number must be conserved at each vertex, or just for the overall process. I can draw a Feynmann diagram with a Z0 boson as the exchange particle, but I'm not convinced that this is correct.
     
  2. jcsd
  3. Apr 26, 2010 #2

    vela

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    Yes, it is, but it's not mediated by the Z boson.
     
  4. Apr 26, 2010 #3
    In that case, it must be a photon?
     
  5. Apr 26, 2010 #4

    vela

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    No. If the process involves neutrinos, it's a weak interaction.
     
  6. Apr 26, 2010 #5
    I think I'm being distracted by thinking that there's no transfer of charge between the initial and final states.

    Had another go, and now have a diagram that looks like a scattering process with the exchange of a W+ boson.
     
  7. Apr 26, 2010 #6

    vela

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    Sounds right!
     
  8. Apr 26, 2010 #7
    Thanks!
     
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