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A ~ 14 Days Star with Two Phase-Locked Modes of Pulsation in the Eros Database

J. P. Beaulieu·R. Buchler·M. J. Goupil·Z. Kollath
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Abstract

Using CCD photometry obtained by the EROS collaboration in 1991-1993, we have discovered an LMC variable star with a light curve that is oscillating with a mean period of $\sim 14$ days and an amplitude of $\sim$ 0.3 mag. The oscillations appear with irregular amplitude variations. The Fourier spectrum shows that the pulsation of this star is phase locked between two modes of frequencies $f_0$ and 1.5$\times f_0$. Moreover, this object has strong $H α$ and $H β$ emission lines and neutral lines of Helium that suggest a spectral type between late O and early B. In a preliminary analysis, we derive a luminosity of $ L=3.4-3.8L_\odot$ and an effective temperature in the range $\log(T_{eff}) =3.85-4.2$.

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J. P. Beaulieu, R. Buchler, M. J. Goupil, Z. Kollath. 1997-08-08. A ~ 14 Days Star with Two Phase-Locked Modes of Pulsation in the Eros Database. https://arxiv.org/abs/astro-ph/9708074

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