Answer to Question #88625 in Atomic and Nuclear Physics for Sridhar

Question

An electron capture reaction
1)a neutrino is created
2)antineutrino is created
3)beta + is emitted
4)beta- is emitted

Answer 1

The electron capture process looks like the following:

$$p+e^{-} \, \rightarrow \, n + \nu_e$$

Hence, in order to save the lepton flavour number we see electron neutrino appearing in the right hand side of the process expression.

Answer: 1) a neutrino is created.