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arXiv · 1608.02945

A planet in an 840-d orbit around a Kepler main-sequence A star found from phase modulation of its pulsations

Simon J. Murphy·Timothy R. Bedding·Hiromoto Shibahashi
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Abstract

We have detected a 12 M$_{\rm Jup}$ planet orbiting in or near the habitable zone of a main-sequence A star via the pulsational phase shifts induced by orbital motion. The planet has an orbital period of $840\pm20$ d and an eccentricity of 0.15. All known planets orbiting main-sequence A stars have been found via the transit method or by direct imaging. The absence of astrometric or radial-velocity detections of planets around these hosts makes ours the first discovery using the orbital motion. It is also the first A star known to host a planet within 1$\sigma$ of the habitable zone. We find evidence for planets in a large fraction of the parameter space where we are able to detect them. This supports the idea that A stars harbor high-mass planets in wide orbits.

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Simon J. Murphy, Timothy R. Bedding, Hiromoto Shibahashi. 2016-08-09. A planet in an 840-d orbit around a Kepler main-sequence A star found from phase modulation of its pulsations. https://doi.org/10.3847/2041-8205%2F827%2F1%2Fl17

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