- #1
HypnoFunk
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Hello there,
I am looking at the decays of Heavy sterile neutrinos in the their mass states to Z bosons.
Using the feynman rules, how would I go about calculating the decay amplitude. I have only ever seen cases where the Z boson is a propagator. Would my expression look something like this:
[itex]
M = \kappa\frac{g}{2\cos\theta_{W}}\overline{\nu_{1}}(2)\gamma^{\mu}P_{L}N_{m}(1)\epsilon_{\mu}^{*}(3)
[/itex]
where [itex]\kappa[/itex] is some constant. Essentially the Feynman diagram looks like a standard weak vertex between two neutrinos. The only difference is that one of them is Heavy (GeV-TeV) scale. However my question really is about whether I just take the standard vertex and include the [itex]\epsilon^{*\mu}[/itex] vector for the outgoing Z-boson.
The standard vertex factor reads
[itex]
-i\frac{g}{2\cos\theta_{W}}\kappa\gamma^{\mu}P_{L}
[/itex]
Is it enough for me to just add [itex]\epsilon^{\mu *}[/itex] for the outgoing Z boson?
Thank you to anyone who can help.
I am looking at the decays of Heavy sterile neutrinos in the their mass states to Z bosons.
Using the feynman rules, how would I go about calculating the decay amplitude. I have only ever seen cases where the Z boson is a propagator. Would my expression look something like this:
[itex]
M = \kappa\frac{g}{2\cos\theta_{W}}\overline{\nu_{1}}(2)\gamma^{\mu}P_{L}N_{m}(1)\epsilon_{\mu}^{*}(3)
[/itex]
where [itex]\kappa[/itex] is some constant. Essentially the Feynman diagram looks like a standard weak vertex between two neutrinos. The only difference is that one of them is Heavy (GeV-TeV) scale. However my question really is about whether I just take the standard vertex and include the [itex]\epsilon^{*\mu}[/itex] vector for the outgoing Z-boson.
The standard vertex factor reads
[itex]
-i\frac{g}{2\cos\theta_{W}}\kappa\gamma^{\mu}P_{L}
[/itex]
Is it enough for me to just add [itex]\epsilon^{\mu *}[/itex] for the outgoing Z boson?
Thank you to anyone who can help.
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