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jazznaz
Apr26-10, 06:50 AM
1. The problem statement, all variables and given/known data

Is the following process a valid interaction?

\nu_\mu \bar{\nu}_e \rightarrow e^+ \mu

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.

vela
Apr26-10, 02:54 PM
Yes, it is, but it's not mediated by the Z boson.

jazznaz
Apr26-10, 03:11 PM
In that case, it must be a photon?

vela
Apr26-10, 03:12 PM
No. If the process involves neutrinos, it's a weak interaction.

jazznaz
Apr26-10, 03:16 PM
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.

vela
Apr26-10, 03:19 PM
Sounds right!

jazznaz
Apr26-10, 03:20 PM
Thanks!