# X-Ray Variability in the Young Massive Triple θ2 Orionis A

@article{Schulz2006XRayVI,
title={X-Ray Variability in the Young Massive Triple $\theta$2 Orionis A},
author={Norbert S. Schulz and Paola Testa and David P. Huenemoerder and Kazunori Ishibashi and Claude R. Canizares},
journal={The Astrophysical Journal},
year={2006},
volume={653},
pages={636-646}
}
• Published 20 August 2006
• Physics
• The Astrophysical Journal
Massive stars rarely show intrinsic X-ray variability. One exception is θ2 Ori A, which has shown strong variability over the last 5 years. We observed a large outburst of the X-ray source with the High Energy Transmission Grating Spectrometer on board Chandra and compare the emissivity and line properties in states of low and high flux. The low state indicates temperatures well above 25 MK. In the high state we find high emissivities in the range from 3 to over 100 MK. The outburst event in…

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