K2-291b: A Rocky Super-Earth in a 2.2 day Orbit

© 2019. The American Astronomical Society. All rights reserved.. K2-291 is a solar-type star with a radius of R ∗ = 0.899 ±0.034 R and mass of M ∗ = 0.934 ±0.038 M . From the K2 C13 data, we found one super-Earth planet (R p = 1.589 -0.072+0.095 R ⊕ ) transiting this star on a short period orbit (P...

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Format: Article
Language:English
Published: American Astronomical Society 2021
Online Access:https://hdl.handle.net/1721.1/132398
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description © 2019. The American Astronomical Society. All rights reserved.. K2-291 is a solar-type star with a radius of R ∗ = 0.899 ±0.034 R and mass of M ∗ = 0.934 ±0.038 M . From the K2 C13 data, we found one super-Earth planet (R p = 1.589 -0.072+0.095 R ⊕ ) transiting this star on a short period orbit (P = 2.225177 -6.8e-5+6.6e-5 days). We followed this system up with adaptive-optic imaging and spectroscopy to derive stellar parameters, search for stellar companions, and determine a planet mass. From our 75 radial velocity measurements using High Resolution Echelle Spectrometer on Keck I and High Accuracy Radial velocity Planet Searcher in the northern hemisphere on Telescopio Nazionale Galileo, we constrained the mass of K2-291 b to M p = 6.49 ±1.16 M ⊕ . We found it necessary to model correlated stellar activity radial velocity signals with a Gaussian process (GP) in order to more accurately model the effect of stellar noise on our data; the addition of the GP also improved the precision of this mass measurement. With a bulk density of ρ = 8.84 -2.03+2.50 g cm -3 , the planet is consistent with an Earth-like rock/iron composition and no substantial gaseous envelope. Such an envelope, if it existed in the past, was likely eroded away by photoevaporation during the first billion years of the star's lifetime.
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spelling mit-1721.1/1323982022-04-01T17:27:48Z K2-291b: A Rocky Super-Earth in a 2.2 day Orbit © 2019. The American Astronomical Society. All rights reserved.. K2-291 is a solar-type star with a radius of R ∗ = 0.899 ±0.034 R and mass of M ∗ = 0.934 ±0.038 M . From the K2 C13 data, we found one super-Earth planet (R p = 1.589 -0.072+0.095 R ⊕ ) transiting this star on a short period orbit (P = 2.225177 -6.8e-5+6.6e-5 days). We followed this system up with adaptive-optic imaging and spectroscopy to derive stellar parameters, search for stellar companions, and determine a planet mass. From our 75 radial velocity measurements using High Resolution Echelle Spectrometer on Keck I and High Accuracy Radial velocity Planet Searcher in the northern hemisphere on Telescopio Nazionale Galileo, we constrained the mass of K2-291 b to M p = 6.49 ±1.16 M ⊕ . We found it necessary to model correlated stellar activity radial velocity signals with a Gaussian process (GP) in order to more accurately model the effect of stellar noise on our data; the addition of the GP also improved the precision of this mass measurement. With a bulk density of ρ = 8.84 -2.03+2.50 g cm -3 , the planet is consistent with an Earth-like rock/iron composition and no substantial gaseous envelope. Such an envelope, if it existed in the past, was likely eroded away by photoevaporation during the first billion years of the star's lifetime. 2021-09-20T18:22:14Z 2021-09-20T18:22:14Z 2020-10-19T17:33:43Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/132398 en 10.3847/1538-3881/AAFE83 Astronomical Journal Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Astronomical Society The American Astronomical Society
spellingShingle K2-291b: A Rocky Super-Earth in a 2.2 day Orbit
title K2-291b: A Rocky Super-Earth in a 2.2 day Orbit
title_full K2-291b: A Rocky Super-Earth in a 2.2 day Orbit
title_fullStr K2-291b: A Rocky Super-Earth in a 2.2 day Orbit
title_full_unstemmed K2-291b: A Rocky Super-Earth in a 2.2 day Orbit
title_short K2-291b: A Rocky Super-Earth in a 2.2 day Orbit
title_sort k2 291b a rocky super earth in a 2 2 day orbit
url https://hdl.handle.net/1721.1/132398