Searching for new white dwarf pulsators for TESS observations at Konkoly Observatory

TL;DR

This study identified two new white dwarf pulsators suitable for TESS, expanding the catalog of known ZZ Ceti stars and providing preliminary asteroseismic data, with additional variable stars discovered in the field.

Contribution

First identification of new white dwarf pulsators for TESS, including detailed frequency analysis and preliminary asteroseismic insights, along with discovery of other variable stars.

Findings

Two new ZZ Ceti stars identified: EGGR 120 and WD 1310+583.

17 significant pulsation frequencies determined for WD 1310+583.

Additional variable stars discovered in the observed fields.

Abstract

We present the results of our survey searching for new white dwarf pulsators for observations by the TESS space telescope. We collected photometric time-series data on 14 white dwarf variable-candidates at Konkoly Observatory, and found two new bright ZZ Ceti stars, namely EGGR 120 and WD 1310+583. We performed the Fourier-analysis of the datasets. In the case of EGGR 120, which was observed on one night only, we found one significant frequency at 1332 microHz with 2.3 mmag amplitude. We successfully observed WD 1310+583 on eight nights, and determined 17 significant frequencies by the whole dataset. Seven of them seem to be independent pulsation modes between 634 and 2740 microHz, and we performed preliminary asteroseismic investigations of the star utilizing six of these periods. We also identified three new light variables on the fields of white dwarf candidates: an eclipsing binary, a candidate delta Scuti/beta Cephei and a candidate W UMa-type star.