In his book "Modern Particle Physics" Mark Thomson has the following Figures for $e^{+}e^{-}\rightarrow \mu^{+}\mu^{-}$:

(i) Concerning the first Feynman diagram in Figure 6.2: Couldn't the intermediate loop also contain $\mu^{-}\mu^{+}$?

(ii) Concerning the second Feynman diagram in Figure 6.2: This is how I understand what is drawn. Could sb please tell me whether my understanding is correct?

(iii) Concerning the third Feynman diagram in Figure 6.2: Here I drew my understanding of the diagram:

So basically an $e^{-}$ emits a photon $\gamma$ but is still an $e^{-}$ and this emitted photon is absorbed by a muon $\mu^{-}$ which still stays a muon $\mu^{-}$. Is that diagramm correct? :-)

Thanks a lot!

In his book "Modern Particle Physics" Mark Thomson has the following Figures for $e^{+}e^{-}\rightarrow \mu^{+}\mu^{-}$:

(i) Concerning the first Feynman diagram in Figure 6.2: Couldn't the intermediate loop also contain $\mu^{-}\mu^{+}$?

(ii) Concerning the second Feynman diagram in Figure 6.2: This is how I understand what is drawn. Could somebody please tell me whether my understanding is correct?

(iii) Concerning the third Feynman diagram in Figure 6.2: Here I drew my understanding of the diagram:

So basically an $e^{-}$ emits a photon $\gamma$ but is still an $e^{-}$ and this emitted photon is absorbed by a muon $\mu^{-}$ which still stays a muon $\mu^{-}$. Is that diagram correct? :-)