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arXiv · 1806.07279

Sliding along the Eddington Limit -- Heavy-Weight Central Stars of Planetary Nebulae

Lisa Löbling
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Abstract

Due to thermal pulses, asymptotic giant branch (AGB) stars experience periods of convective mixing that provide ideal conditions for slow neutron-capture nucleosynthesis. These processes are affected by large uncertainties and are still not fully understood. By the lucky coincidence that about a quarter of all post-AGB stars turn hydrogen-deficient in a final flash of the helium-burning shell, they display nuclear processed material at the surface providing an unique insight to nucleosynthesis and mixing. We present results of non-local thermodynamic equilibrium spectral analyses of the extremely hot, hydrogen-deficient, PG 1159-type central stars of the Skull Nebula NGC 246 and the "Galactic Soccerballs" Abell 43 and NGC 7094.

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Lisa Löbling. 2018-06-19. Sliding along the Eddington Limit -- Heavy-Weight Central Stars of Planetary Nebulae. https://doi.org/10.3390/galaxies6020065

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