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arXiv · 0712.3270

First Observation of Planet-Induced X-ray Emission: The System HD 179949

S. H. Saar·M. Cuntz·V. L. Kashyap·J. C. Hall
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Abstract

We present the first observation of planet-induced stellar X-ray activity, identified for the HD 179949 system, using Chandra / ACIS-S. The HD 179949 system consists of a close-in giant planet orbiting an F9V star. Previous ground-based observations already showed enhancements in Ca II K in phase with the planetary orbit. We find an ~30% increase in the X-ray flux over quiescent levels coincident with the phase of the Ca II enhancements. There is also a trend for the emission to be hotter at increased fluxes, confirmed by modeling, showing the enhancement at ~1 keV compared to ~0.4 keV for the background star.

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S. H. Saar, M. Cuntz, V. L. Kashyap, J. C. Hall. 2008-02-15. First Observation of Planet-Induced X-ray Emission: The System HD 179949. https://doi.org/10.1017/s1743921308016414

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