Analysis of TESS field eclipsing binary star V948 Her: a pulsating or non-pulsating star?

TL;DR

This study analyzes the eclipsing binary V948 Her using TESS data to determine if it pulsates, revealing it is a non-pulsator despite its primary star being inside the δ Scuti instability strip, thus aiding understanding of non-pulsating stars.

Contribution

The paper provides precise fundamental parameters of V948 Her and clarifies its non-pulsating nature despite its primary star being in the instability strip.

Findings

V948 Her is a non-pulsator with no significant pulsation frequencies.

The primary star is located inside the δ Scuti instability strip.

The system's age is approximately 1 Gyr.

Abstract

Pulsating stars occupy a significant place in the H-R diagram and it was thought that all stars inside the classical instability strip should pulsate. However, recent studies showed that there are many non-pulsating stars placed inside the classical instability strip. The existence of these non-pulsating stars is still a mystery. To deeply understand the properties of these non-pulsating and pulsating stars, one needs precise fundamental stellar parameters (e.g mass). For this purpose, the eclipsing binaries are unique systems. Hence, in this study, we present the TESS data analysis of one candidate pulsating eclipsing binary system V948\,Her. TESS data were used for the binary modelling with the literature radial velocity measurements and the precise fundamental parameters of the system were obtained. The system's age was derived as 1$\pm$0.24 Gyr. The positions of the binary components in the H-R diagram were examined and the primary component was found inside the $\delta$\,Scuti instability strip. However, in the frequency analysis of TESS data, we found no significant pulsation frequencies. Only the harmonics of the orbital periods were obtained in the analysis. Therefore, the system was classified as a non-pulsator. V948\,Her is an important object to understand the nature of non-pulsating stars inside the $\delta$\,Scuti instability strip.