Glossary
The CNO Cycle

While on the Main Sequence the primary nuclear reactions within the core of Sun involve the conversion of hydrogen (1H) to Helium (4He) (and "by-products"). The CNO cycle is an independent route to the PP Chains possible when the star contains a significant amount of Carbon (12C) . There are two routes, both following the same initial steps:
12C + 1H converted to 13N + photon
13N converted to 13C + e+ + nue
13C + 1H converted to 14N + photon
14N + 1H converted to 150 + photon
150 converted to 15N + e+ + nue
(where e+ is a positron and nue is an electron-neutrino).

However hereafter there are two possible routes, the first obviously being the dominant one:
  • (99.96% probable)
    15N + 1H converted to 12C + 4He

  • (0.04% probable)
    15He + 1H converted to 16O + photon
    16He + 1H converted to 17F + photon
    17F converted to 170 + e+ nee
    17O + 1H converted to 14N + 4He