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arXiv · 1806.00769

Periodicity in the Light Curve of P Cygni - Indication for a Binary Companion?

Amir M. Michaelis·Amit Kashi·Nino Kochiashvili
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Abstract

We use observations of the Luminous Blue Variable (LBV) P Cygni spanning seven decades, along with signal processing methods, to identify a periodicity in the stellar luminosity. We find a distinct period of $4.7 \pm 0.3$ years together with shorter periods. The periodicity is a possible indication of a binary companion passing in an eclipse-like event from the dense LBV wind, and if so it is the first observational indication that P Cygni is a binary system. This may support models that contribute giant LBV eruptions to interaction with a binary companion. We discuss other interpretations for the periodicity as well.

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Amir M. Michaelis, Amit Kashi, Nino Kochiashvili. 2018-06-24. Periodicity in the Light Curve of P Cygni - Indication for a Binary Companion?. https://doi.org/10.1016/j.newast.2018.06.001

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