Abstract
We investigate directly imaging exoplanets around eclipsing binaries using the eclipse as a natural tool for dimming the binary and thus increasing the planet to star brightness contrast. At eclipse, the binary becomes pointlike, making coronagraphy possible. We select binaries where the planet-star contrast would be boosted by >10× during eclipse, making it possible to detect a planet that is ⪆10× fainter or in a star system that is ∼2-3× more massive than otherwise. Our approach will yield insights into planet occurrence rates around binaries versus individual stars. We consider both self-luminous (SL) and reflected light (RL) planets. In the SL case, we select binaries whose age is young enough so that an orbiting SL planet would remain luminous; in U Cep and AC Sct, respectively, our method is sensitive to SL planets of ∼4.5 and ∼9 M J with current ground- or near-future space-based instruments and ∼1.5 and ∼6 M J with future ground-based observatories. In the RL case, there are three nearby (≲50 pc) systems - V1412 Aql, RR Cae, and RT Pic - around which a Jupiter-like planet at a planet-star separation of ⪆20 mas might be imaged with future ground- and space-based coronagraphs. A Venus-like planet at the same distance might be detectable around RR Cae and RT Pic. A habitable Earth-like planet represents a challenge; while the planet-star contrast at eclipse and planet flux are accessible with a 6-8 m space telescope, the planet-star separation is 1/3-1/4 of the angular separation limit of modern coronagraphy.
Original language | English (US) |
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Article number | 131 |
Journal | Astronomical Journal |
Volume | 160 |
Issue number | 3 |
DOIs | |
State | Published - Sep 2020 |
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science
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Compilation of 289 eclipsing binaries parameters
Bellotti, S. (Creator), Zabludoff, A. I. (Creator), Belikov, R. (Creator), Guyon, O. (Creator) & Rathi, C. (Creator), Centre de Donnees Strasbourg (CDS), 2020
DOI: 10.26093/cds/vizier.51600131, https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/160/131
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