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We follow the scenario of formation of second generation stars in globularclusters by matter processed by hot bottom burning (HBB) in massive asymptoticgiant branch (AGB) stars and Super AGB stars (SAGB). In the cluster NGC 2419 weassume the presence of an extreme population directly formed from the AGB andSAGB ejecta, so we can directly compare the yields for a metallicity Z=0.0003with the chemical inventory of the cluster NGC 2419. At such a low metallicity,the HBB temperatures (well above 108K) allow a very advanced nucleosynthesis.Masses of about 6Mo deplete Mg and synthesize Si, going beyond Al, so thislatter element results only moderately enhanced; sodium can not be enhanced.The models are consistent with the observations, although the predicted Mgdepletion is not as strong as in the observed stars. We predict that the oxygenabundance must be depleted by a huge factor in the Mg poor stars. The HBBtemperatures are close to the region where other p capture reactions on heaviernuclei become possible. We show that high potassium abundance found in Mg poorstars can be achieved during HBB, by p captures on the argon nuclei, if therelevant cross section(s) are larger than listed in the literature or if theHBB temperature is higher. Finally, we speculate that some calcium productionis occurring owing to proton capture on potassium. We emphasize the importanceof a strong effort to measure a larger sample of abundances in this cluster.

Super AGB and AGB evolution and the chemical inventory in NGC 2419