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arXiv · 1811.03043

Retired A Stars and Their Companions VIII: 15 New Planetary Signals Around Subgiants and Transit Parameters for California Planet Search Planets with Subgiant Hosts

Jacob K. Luhn·Fabienne A. Bastien·Jason T. Wright·John A. Johnson·Andrew W. Howard·Howard Isaacson
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Abstract

We present the discovery of 7 new planets and 8 planet candidates around subgiant stars, as additions to the known sample of planets around "retired A stars" (Johnson et al. 2006). Among these are the possible first 3-planet systems around subgiant stars, HD 163607 and HD 4917. Additionally, we present calculations of possible transit times, durations, depths, and probabilities for all known planets around subgiant (3 < log g < 4) stars, focused on possible transits during the TESS mission. While most have transit probabilities of 1-2%, we find that there are 3 planets with transit probabilities > 9%.

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Jacob K. Luhn, Fabienne A. Bastien, Jason T. Wright, John A. Johnson, Andrew W. Howard, Howard Isaacson. 2018-11-07. Retired A Stars and Their Companions VIII: 15 New Planetary Signals Around Subgiants and Transit Parameters for California Planet Search Planets with Subgiant Hosts. https://doi.org/10.3847/1538-3881%2Faaf5d0

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