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arXiv · 1405.5075

Discovery of a new PG1159 (GW Vir) Pulsator

S. O. Kepler·Luciano Fraga·Don Earl Winget·Keaton Bell·Alejandro H. Corsico·Klaus Werner
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Abstract

We report the discovery of pulsations in the spectroscopic PG 1159 type pre-white dwarf SDSS J075415.12+085232.18. Analysis of the spectrum by Werner, Rauch and Kepler (2014) indicated Teff=120 000+/-10 000 K, log g=7.0+/-0.3, mass M=0.52+/-0.02 Msun, C/He=0.33 by number. We obtained time-series images with the SOAR 4.1 m telescope and 2.1 m Otto Struve telescope at McDonald Observatory and show the star is also a variable PG 1159 type star, with dominant period of 525 s.

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S. O. Kepler, Luciano Fraga, Don Earl Winget, Keaton Bell, Alejandro H. Corsico, Klaus Werner. 2014-05-20. Discovery of a new PG1159 (GW Vir) Pulsator. https://doi.org/10.1093/mnras%2Fstu1019

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