# Precise determination of stellar parameters of the ZZ Ceti and DAZ white dwarf GD 133 through asteroseismology

## TL;DR

This study uses asteroseismology to precisely determine the physical parameters of the white dwarf GD 133, revealing insights into its structure, rotation, and potential planetary system.

## Contribution

The paper presents the first detailed asteroseismological analysis of GD 133, providing accurate stellar parameters and rotation period based on multi-year photometric data.

## Key findings

- Stellar mass estimated at 0.630 solar masses
- Effective temperature determined as 12400 K
- Rotation period approximately 7 days

## Abstract

An increasing number of white dwarf stars show atmospheric chemical composition polluted by heavy elements accreted from debris disk material. The existence of such debris disks strongly suggests the presence of one or more planet(s) whose gravitational interaction with rocky planetesimals is responsible for their disruption by tidal effect. The ZZ Ceti pulsator and polluted DAZ white dwarf GD 133 is a good candidate for searching for such a potential planet. We started in 2011 a photometric follow-up of its pulsations. As a result of this work in progress, we used the data gathered from 2011 to 2015 to make an asteroseismological analysis of GD 133, providing the star parameters from a best fit model with $M$/$M_{\odot}$ = 0.630 $\pm$ 0.002, $T_{\rm eff}$ = 12400 K $\pm$ 70 K, log($M_{\rm He}/M$) = -2.00 $\pm$ 0.02, log($M_{\rm H}/M$) = -4.50 $\pm$ 0.02 and determining a rotation period of $\approx$ 7 days.