DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Transit least-squares survey. IV. Earth-like transiting planets expected from the PLATO mission

Heller, René and Harre, Jan-Vincent and Samadi, R. (2022) Transit least-squares survey. IV. Earth-like transiting planets expected from the PLATO mission. Astronomy & Astrophysics, 664, A11. EDP Sciences. doi: 10.1051/0004-6361/202141640. ISSN 0004-6361.

[img] PDF - Published version

Official URL: https://www.aanda.org/articles/aa/full_html/2022/09/aa41640-21/aa41640-21.html


In its long-duration observation phase, the PLATO satellite (scheduled for launch in 2026) will observe two independent, non-overlapping fields, nominally one in the northern hemisphere and one in the southern hemisphere, for a total of four years. The exact duration of each pointing will be determined two years before launch. Previous estimates of PLATO’s yield of Earth-sized planets in the habitable zones (HZs) around solar-type stars ranged between 6 and 280. We use the PLATO Solar-like Light curve Simulator (PSLS) to simulate light curves with transiting planets around bright (mV ≤ 11) Sun-like stars at a cadence of 25 s, roughly representative of the > 15, 000 targets in PLATO’s high-priority P1 sample (mostly F5-K7 dwarfs and subdwarfs). Our study includes light curves generated from synchronous observations of 6, 12, 18, and 24 of PLATO’s 12 cm aperture cameras over both 2 yr and 3 yr of continuous observations. Automated detrending is done with the W¯otan software, and post-detrending transit detection is performed with the transit least-squares (TLS) algorithm. Light curves combined from 24 cameras yield true positive rates (TPRs) near unity for planets ≥1.2 R⊕ with two transits. If a third transit is in the light curve, planets as small as 1 R⊕ are recovered with TPR ∼ 100 %. We scale the TPRs with the expected number of stars in the P1 sample and with modern estimates of the exoplanet occurrence rates and predict the detection of planets with 0.5 R⊕ ≤ Rp ≤ 1.5 R⊕ in the HZs around F5-K7 dwarf stars. For the long-duration observation phase (2 yr + 2 yr) strategy we predict 11–34 detections, and for the (3 yr + 1 yr) strategy we predict 8–25 discoveries. These estimates neglect exoplanets with monotransits, serendipitous detections in stellar samples P2–P5, a dedicated removal of systematic effects, and a possible bias of the P1 sample toward brighter stars and high camera coverage due to noise requirements. As an opposite effect, Earth-sized planets might typically exhibit transits around P1 sample stars shallower than we have assumed since the P1 sample will be skewed toward spectral types earlier than the Sun-like stars assumed in our simulations. Moreover, our study of the effects of stellar variability on shallow transits of Earth-like planets illustrates that our estimates of PLATO’s planet yield, which we derive using a photometrically quiet star similar to the Sun, must be seen as upper limits. In conclusion, PLATO’s detection of about a dozen Earth-sized planets in the HZs around solar-type stars will mean a major contribution to this as yet poorly sampled part of the exoplanet parameter space with Earth-like planets.

Item URL in elib:https://elib.dlr.de/189311/
Document Type:Article
Title:Transit least-squares survey. IV. Earth-like transiting planets expected from the PLATO mission
AuthorsInstitution or Email of AuthorsAuthor's ORCID iDORCID Put Code
Heller, RenéMax-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, GermanyUNSPECIFIEDUNSPECIFIED
Harre, Jan-VincentUNSPECIFIEDhttps://orcid.org/0000-0001-8935-2472UNSPECIFIED
Samadi, R.LESIA, Observatoire de Paris, Universite PSL, CNRS, Sorbonne Universite, Univ. Paris Diderot, Sorbonne Paris Cite, 5 Place Jules Janssen, 92195, Meudon, France );UNSPECIFIEDUNSPECIFIED
Date:September 2022
Journal or Publication Title:Astronomy & Astrophysics
Refereed publication:Yes
Open Access:Yes
Gold Open Access:No
In ISI Web of Science:Yes
Page Range:A11
Publisher:EDP Sciences
Keywords:methods: data analysis – occultations – planets and satellites: detection – stars: solar-type – techniques: photometric
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Space Exploration
DLR - Research area:Raumfahrt
DLR - Program:R EW - Space Exploration
DLR - Research theme (Project):R - Project PLATO - PMC and Science
Location: Berlin-Adlershof
Institutes and Institutions:Institute of Planetary Research > Extrasolar Planets and Atmospheres
Deposited By: Harre, Jan-Vincent
Deposited On:31 Oct 2022 14:51
Last Modified:31 Oct 2022 14:51

Repository Staff Only: item control page

Help & Contact
electronic library is running on EPrints 3.3.12
Website and database design: Copyright © German Aerospace Center (DLR). All rights reserved.