Neutron energies at which C14 is produced

[radagast]

Some time back a friend (PhD Nuclear Engineer), told me that the energies a neutron needed to form C14 from nitrogen were (and this is where my memory gets real fuzzy) around 15 MEV. Furthermore that neither nuclear explosions or the Sun produced neutrons of this energy. The implications were they were formed in supernovas and survived due to relativistic time dialation.

This just seems to tickle my BS meter, but having no knowledge of nuclear physics, to speak of, I'd rather hear some confirmation of this before I go accepting it as likely or dismissing it.

 

[eagleone]

No you probably miss heard that. Eg. C14 forms from N14 and slow neutrons from secondary cosmic radiation in atmosphere, if you substitute this neutrons with neutrons of higher eng. You’ll get tritium from N14 (in atmosphere again :)...

Well,C14 is not the best survivor with it’s half time live of ~5730 :)...

p.s. Hope this data is correct after all I’m no n. physicist (although by may neighbor I’m nuclear biologist