Exoplanet Classification and Yield Estimates for Direct Imaging Missions
AuthorKopparapu, Ravi Kumar
Batalha, Natalie M.
Mulders, Gijs D.
AffiliationUniv Arizona, Lunar & Planetary Lab
Keywordsplanets and satellites: atmospheres
planets and satellites: gaseous planets
planets and satellites: terrestrial planets
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationRavi Kumar Kopparapu et al 2018 ApJ 856 122
Rights© 2018. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractFuture NASA concept missions that are currently under study, like the Habitable Exoplanet Imaging Mission (HabEx) and the Large Ultra-violet Optical Infra Red Surveyor, could discover a large diversity of exoplanets. We propose here a classification scheme that distinguishes exoplanets into different categories based on their size and incident stellar flux, for the purpose of providing the expected number of exoplanets observed (yield) with direct imaging missions. The boundaries of this classification can be computed using the known chemical behavior of gases and condensates at different pressures and temperatures in a planetary atmosphere. In this study, we initially focus on condensation curves for sphalerite ZnS, H2O, CO2, and CH4. The order in which these species condense in a planetary atmosphere define the boundaries between different classes of planets. Broadly, the planets are divided into rocky planets (0.5-1.0 R-circle plus), super-Earths (1.0-1.75 R-circle plus), sub-Neptunes (1.75-3.5 R-circle plus), sub-Jovians (3.5-6.0 R-circle plus), and Jovians (6-14.3 R-circle plus) based on their planet sizes, and "hot," "warm," and "cold" based on the incident stellar flux. We then calculate planet occurrence rates within these boundaries for different kinds of exoplanets, eta(planet), using the community coordinated results of NASA's Exoplanet Program Analysis Group's Science Analysis Group-13 (SAG-13). These occurrence rate estimates are in turn used to estimate the expected exoplanet yields for direct imaging missions of different telescope diameters.
VersionFinal published version
SponsorsNASA Astrobiology Institute's Virtual Planetary Laboratory lead team - NASA [NNH05ZDA001C]; GSFC Sellers Exoplanet Environments Collaboration (SEEC) - NASA Planetary Science Divisions Internal Scientist Funding Model
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