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

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.

arXiv commentAccepted to New Astronomy

References in corpus (6)

• NGC 300 OT2008-1 As a Scaled-Down Version of the Eta Carinae Great Eruption
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