SIMBAD references

We present full stellar evolution and parametric models of the surface abundance evolution of ¹⁶O, ²²Ne, ²³Na, and the magnesium isotopes in an extremely metal poor intermediate-mass star (M_ZAMS=5 M_☉, where ZAMS stands for the zero-age main sequence, and Z=0.0001). ¹⁶O and ²²Ne are injected into the envelope by the third dredge-up following thermal pulses on the asymptotic giant branch. These species and the initially present ²⁴Mg are depleted by hot bottom burning (HBB) during the interpulse phase. As a result, ²³Na, ²⁵Mg, and ²⁶Mg are enhanced. If the HBB temperatures are sufficiently high for this process to deplete oxygen efficiently, ²³Na is first produced and then depleted during the interpulse phase. Although the simultaneous depletion of ¹⁶O and enhancement of ²³Na is possible, the required fine-tuning of the dredge-up and HBB casts some doubt on the robustness of this process as the origin of the O-Na anticorrelation observed in globular cluster stars. However, a very robust prediction of our models are low ²⁴Mg/²⁵Mg and ²⁴Mg/²⁶Mg ratios whenever significant ¹⁶O depletion can be achieved. This seems to be in stark contrast to recent observations of the magnesium isotopic ratios in the globular cluster NGC 6752.