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The Nature of the Driving Mechanism in the Pulsating Hybrid PG 1159 Star Abell 43

P. -O. Quirion·G. Fontaine·P. Brassard
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Abstract

We extend our previous pulsational stability analyses of PG 1159 stars by modeling the hybrid PG 1159 type star Abell 43. We show that the standard kappa-mechanism due to the ionization of C and O in the envelope of this H-rich PG 1159 star is perfectly able to drive g-mode pulsations. Thus, contrary to a recent suggestion, there is no need to invoke any new or exotic mechanism to explain the pulsational instabilities observed in this particular star. Our expected instability band for l = 1 modes extends in period from ~ 2604 s to ~ 5529 s, which is consistent with the available photometric observations of Abell 43. We also suggest that efforts to detect luminosity variations in its sibling NGC 7094 be pursued.

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P. -O. Quirion, G. Fontaine, P. Brassard. 2005-05-29. The Nature of the Driving Mechanism in the Pulsating Hybrid PG 1159 Star Abell 43. https://doi.org/10.1051/0004-6361%3A20053394

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