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arXiv · 1402.6551

Amplitude variability in satellite photometry of the non-radially pulsating O9.5V star zeta Oph

Ian D. Howarth·K. J. F. Goss·I. R. Stevens·W. J. Chaplin·Y. Elsworth
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Abstract

We report a time-series analysis of satellite photometry of the non-radially pulsating Oe star zeta Oph, principally using data from SMEI obtained 2003--2008, but augmented with MOST and WIRE results. Amplitudes of the strongest photometric signals, at 5.18, 2.96, and 2.67/d, each vary independently over the 6-year monitoring period (from ca. 30 to <2 mmag at 5.18/d), on timescales of hundreds of days. Signals at 7.19/d and 5.18/d have persisted (or recurred) for around two decades. Supplementary spectroscopic observations show an H-alpha emission episode in 2006; this coincided with small increases in amplitudes of the three strongest photometric signals.

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Ian D. Howarth, K. J. F. Goss, I. R. Stevens, W. J. Chaplin, Y. Elsworth. 2014-03-08. Amplitude variability in satellite photometry of the non-radially pulsating O9.5V star zeta Oph. https://doi.org/10.1093/mnras%2Fstu398

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