Lets see the reaction:

$e^- \mu^- \to e^- \pi^- \nu_\mu$

I suppose, that this reaction occurs as follows

$e^- \mu^- \to e^- \mu^- \pi^+ \pi^- \to e^- \pi^- \nu_\mu$

Is it possible at energy less than 2*140 MeV?


The same is for the analogous proton-muon reaction

$p^+ \mu^+ \to p^+ \pi^+ \bar{\nu}_\mu$

What are the **experimental data**?


P.S. This query is important enough. The main solar reaction is

$p^+ p^+ \to d^+ e^+ \nu_e $

If this reaction occurs as follows

$p^+ p^+ \to p^+ p^+ e^- e^+ \to p^+ n \nu_e e^+ \to d^+ e^+ \nu_e$

then  it would require the energy of more than 2*0.511 MeV to take place. Cross section of the main solar reaction will be different.