Pulsation in the white dwarf HE 1017-1352: confirmation of the class of hot DAV stars

TL;DR

This paper confirms that the white dwarf HE 1017-1352 exhibits pulsations characteristic of a new class of hot DA white dwarf stars, expanding understanding of stellar pulsation phenomena.

Contribution

It provides the first detection of pulsations in HE 1017-1352, confirming it as part of a newly identified class of hot DAV white dwarfs.

Findings

Detected four pulsation periods between 508 s and 869 s

Confirmed pulsation modes are consistent with high radial order g-modes

Identified a long period of 1.52 hours likely related to stellar rotation

Abstract

We report the detection of periodic variations on the T_eff ~32 000 K DA white dwarf star HE 1017-1352. We obtained time series photometry using the 4.1 m SOAR telescope on three separate nights for a total of 16.8 h. From the frequency analysis we found four periods of 605 s, 556 s, 508 s and 869 s with significant amplitudes above the 1/1000 false alarm probability detection limit. The detected modes are compatible with low harmonic degree g-mode non-radial pulsations with radial order higher than ~ 9. This detection confirms the pulsation nature of HE 1017-1352 and thus the existence of the new pulsating class of hot DA white dwarf stars. In addition, we detect a long period of 1.52 h, compatible with a rotation period of DA white dwarf stars.