Thirty Two New Bright ZZ Ceti Stars from TESS: Adding Cycles 4 and 5

TL;DR

This paper reports the discovery of 32 new pulsating white dwarf stars from TESS data, providing detailed seismological analysis to estimate their structural parameters and rotation periods.

Contribution

It introduces 32 newly identified ZZ Ceti stars from TESS data and performs comprehensive asteroseismological analysis to determine their physical properties.

Findings

Median stellar mass of pulsators is 0.609 Msun.

Rotation periods range from 4 hours to 1 day.

Consistent mass estimates from asteroseismology and photometry.

Abstract

Analyzing all 120 s and 20 s light curves obtained by the TESS satellite up to Sector 69 - the end of the fifth year of observations - for all known white dwarfs and white dwarf candidates up to G=17.5 mag, we report the discovery of 32 new pulsating DA white dwarf stars. For all objects, we obtained the period spectra and performed a seismological analysis using full evolutionary models to estimate the structural parameters, such as effective temperature, stellar mass, and hydrogen envelope mass. The median stellar mass for the pulsators from asteroseismology is 0.609 Msun, in agreement with the median value from photometric and spectroscopic determinations, 0.602 Msun, excluding the low and extremely-low mass objects. Finally, we found rotational-splitting multiplets for 9 stars, which led to rotation periods between 4 h and 1 d.