Wikipedia says Carbon-14 is formed in the atmosphere by the reaction:
1n + 14N → 14C + 1p
This looks like neutron capture. However, I would expect neutron capture to result in 15N. However, "proton emission" seems to be a rare phenomenon:
15N → 14C + 1p
So, my first question is, does the reaction happen in two stages, or is the proton ejected "immediately"?
Secondly, is this overall type of reaction 1n + → + 1p common? Are there any other examples of such reactions, other than with 14N?