arXiv 0705.21152007-05-15astro-ph

Abell 43: Longest period Planetary Nebula Nucleus variable

J. -E. Solheim, G. Vauclair, A. S. Mukadam, R. Janulis, V. Dobrovolskas

备注：: 5 pages, 5 figures, to be published in Astronomy and Astrophysics
DOI：: 10.1051/0004-6361:20077364

英文摘要：

Based on 24h high speed photometry of the hybrid PG 1159 star Abell 43, we have detected 6 sighificant pulsations with periods between 2380 s and 6075 s. A short (4h) run on the almost spectroscopic twin NGC 7094 central star resulted in detection of 3 low amplitude pulsations with periods between 2000 s and 5000 s. The results are close to predictions for g-mode pulsations driven by the kappa-mechanism induced by the partial ionization of carbon and oxygen.

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