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

L. L. Kiss·A. Derekas·Sz. Meszaros·P. Szekely
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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.

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L. L. Kiss, A. Derekas, Sz. Meszaros, P. Szekely. 2002-08-18. A photometric monitoring of bright high-amplitude delta Scuti stars. I. The double-mode pulsation of V567 Ophiuchi. https://doi.org/10.1051/0004-6361%3A20021201

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