A photometric monitoring of bright high-amplitude delta Scuti stars. I. The double-mode pulsation of V567 Ophiuchi

TL;DR

This study investigates the double-mode pulsation of the high-amplitude delta Scuti star V567 Ophiuchi through extensive photometric observations, revealing two independent frequencies and refining its pulsation periods.

Contribution

First detailed analysis of V567 Ophiuchi's double-mode pulsation using new and existing data, clarifying its secondary period and contributing to asteroseismology.

Findings

Identified two independent pulsation frequencies f_1=6.6879 c/d and f_2=11.8266 c/d.

Confirmed the secondary period with re-analysis of literature data.

Discussed potential implications for stellar structure and evolution.

Abstract

We present the first results of an observational project, which addresses the period changing behaviour of a sample of high-amplitude delta Scuti stars. In this paper we discuss the double-mode nature of V567 Ophiuchi. It was observed on 15 nights in two consecutive years in order to resolve the long-standing ambiguity related to its secondary period. A frequency analysis of almost 5000 individual single-filtered CCD V measurements resulted in two independent frequencies (f_1=6.6879 c/d and f_2=11.8266 c/d) with a ratio of f_1/f_2=0.565. Earlier data taken from the literature were used to refine the dominant period, and the re-analysis supports the existence of the secondary period. Possible asteroseismological implications are briefly discussed.