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Photometric Periodicities of Be/X-ray Pulsars in the Small Magellanic Cloud

P. C. Schmidtke·A. P. Cowley
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Abstract

Analysis of the longterm photometric variability of 7 Be/X-ray-pulsar systems in the Small Magellanic Cloud has been carried out. We find a variety of types of variability are present, including: longterm irregular changes, periodic orbital outbursts due to interaction between the stars (weeks to months), low-amplitude quasi-periodic variations of the equatorial disk (days), and nonradial pulsations of the Be primary star (hours). This is the first time nonradial pulsations have been identified in Be/X-ray binaries, although they were previously known in some single Be stars.

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P. C. Schmidtke, A. P. Cowley. 2005-06-29. Photometric Periodicities of Be/X-ray Pulsars in the Small Magellanic Cloud. https://doi.org/10.1086/491705%2010.1086%2F505752

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