Dredging operational cycle

The sodium yields are also different in the FST model sodium is first created and the destroyed, when the Ne-Na cycle becomes fully operative. In the MLT models the 3rd dredge-up becomes so efficient that Sodium is eventually produced due to 22 Ne burning in the MLT framework the AGB ejecta are expected to have great mass fractions of sodium. 

This cycle operates in the interiors of main sequence stars parallel to the CKO cycle. It produces nuclei of 23Na which together with the products of CNO cycle at a later phase of evolution are dredged up. 

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