(adsbygoogle = window.adsbygoogle || []).push({}); 1. The declaration of the problem, all variables and data given / known

Calculate the decay amplitude of ## \pi ^ 0 ## in an electron-positron pair ## \pi^0 \rightarrow e^+ e^- ##, assuming that the interaction is of the form

## \mathcal {L}_{int} = g \: \partial_{\mu} \phi \: \overline{\psi} \: \gamma ^ {\mu} \: \gamma^5 \: \psi ##

where g is a coupling constant, ## \phi ## is the scalar field corresponding to ## \pi^0 ## and ## \psi ## is the electron field.

2. Relevant equations

3. The attempt of a solution

I don't know how to deduce in general the Feynman rules for a given Lagrangian. We made some examples with some theories (## \phi^4 ##, scalar Yukawa, QED scalar, QED) but for example the term ## \partial_{\mu} \phi ## confuses me

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# Homework Help: How to deduce the Feynman rules?

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