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arXiv · 2502.17577

An Extremely Hot Pulsating Pre-White Dwarf from OGLE

P. Pietrukowicz·K. Werner·M. J. Mroz·M. Ratajczak
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Abstract

We show that the blue 18.3-minute variable object discovered in the Galactic disk by the OGLE-III survey and named OGLE-GD-WD-0001 is a pulsating pre-white dwarf of PG 1159 spectral type. With an effective temperature of about 160,000 K it is among the hottest known pulsators being located close to the blue edge of the GW Virginis instability strip. The long-term OGLE observations indicate that the object has a positive period change rate of about $5 \times 10^{-10}$ $s~s^{-1}$ and thus already contracts. There are no traces of a planetary nebula around this star.

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P. Pietrukowicz, K. Werner, M. J. Mroz, M. Ratajczak. 2025-02-24. An Extremely Hot Pulsating Pre-White Dwarf from OGLE. https://arxiv.org/abs/2502.17577

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