# Electron-positron annihilation to neutrinos

I was wondering, even though the electron-positron annihilation prefers to give us photons, it can turn into neutrinos as well - as far as I understand. My question is, since the equations I have seen is:

$$\nu \bar{\nu} \leftrightarrow e^{+}e^{-}$$

Do this process only give out electron neutrinos, or can it actually create tau and muon neutrinos as well ?

Energy wise, it makes sense, that it is only electron neutrinos, but neutrinos are always strange imo, so maybe they can do stuff I don't really know.

## 1 Answer

Electron positron annihilations can give mu and tau neutrinos as well as electron neutrinos. For a calculation of the probabilities see for example Mu and Tau Neutrino Thermalization and Production in Supernovae: Processes and Timescales.

You might also be interested to read DavidZ's answer to Why does electron-positron annihilation prefer to emit photons?.

• Ah, great. Just what I needed :) – Denver Dang Nov 27 '14 at 10:58