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arXiv · 1911.11954

The Pan-Pacific Planet Search. VIII. Complete results and the occurrence rate of planets around low-luminosity giants

Robert A. Wittenmyer·R. P. Butler·Jonathan Horner·Jake Clark·C. G. Tinney·B. D. Carter·Liang Wang·John Asher Johnson·Michaela Collins
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Abstract

Our knowledge of the populations and occurrence rates of planets orbiting evolved intermediate-mass stars lags behind that for solar-type stars by at least a decade. Some radial velocity surveys have targeted these low-luminosity giant stars, providing some insights into the properties of their planetary systems. Here we present the final data release of the Pan-Pacific Planet Search, a 5-year radial velocity survey using the 3.9m Anglo-Australian Telescope. We present 1293 precise radial velocity measurements for 129 stars, and highlight six potential substellar-mass companions which require additional observations to confirm. Correcting for the substantial incompleteness in the sample, we estimate the occurrence rate of giant planets orbiting low-luminosity giant stars to be approximately 7.8$^{+9.1}_{-3.3}$\%. This result is consistent with the frequency of such planets found to orbit main-sequence A-type stars, from which the PPPS stars have evolved.

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Robert A. Wittenmyer, R. P. Butler, Jonathan Horner, Jake Clark, C. G. Tinney, B. D. Carter, Liang Wang, John Asher Johnson, Michaela Collins. 2019-11-27. The Pan-Pacific Planet Search. VIII. Complete results and the occurrence rate of planets around low-luminosity giants. https://doi.org/10.1093/mnras%2Fstz3378

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