Pulsational frequencies of the eclipsing delta-Scuti star HD 172189

TL;DR

This study analyzes 210 hours of photometric data of the eclipsing delta-Scuti star HD 172189, identifying pulsation frequencies and refining its orbital parameters to aid asteroseismological modeling.

Contribution

It provides the first detailed frequency analysis of HD 172189 and improves the orbital period measurement, supporting future asteroseismological and dynamical studies.

Findings

Six pulsation frequencies identified with high confidence

Refined orbital period of the binary system

Detection of additional pulsation mode at lower confidence

Abstract

The eclipsing delta-Scuti star HD 172189 is a probable member of the open cluster IC 4756 and a promising candidate target for the CoRoT mission. The detection of pulsation modes is the first step in the asteroseismological study of the star. Further, the calculation of the orbital parameters of the binary system allows us to make a dynamical determination of the mass of the star, which works as an important constraint to test and calibrate the asteroseismological models. From a detailed frequency analysis of 210 hours of photometric data of HD 172189 obtained from the STEPHI XIII campaign we have identified six pulsation frequencies with a confidence level of 99% and a seventh with a 65% confidence level in the range between 100-300 uHz. In addiction, three eclipses were observed during the campaign, allowing us to improve the determination of the orbital period of the system.