Bibcode
Souto, D.; Cunha, K.; García-Hernández, D. A.; Zamora, O.; Allende Prieto, C.; Smith, V. V.; Mahadevan, S.; Blake, C.; Johnson, J. A.; Jönsson, H.; Pinsonneault, M.; Holtzman, J.; Majewski, S. R.; Shetrone, M.; Teske, J.; Nidever, D.; Schiavon, R.; Sobeck, J.; García Pérez, A. E.; Gómez Maqueo Chew, Y.; Stassun, K.
Bibliographical reference
The Astrophysical Journal, Volume 835, Issue 2, article id. 239, 12 pp. (2017).
Advertised on:
2
2017
Journal
Citations
41
Refereed citations
38
Description
We report the first detailed chemical abundance analysis of the
exoplanet-hosting M-dwarf stars Kepler-138 and Kepler-186 from the
analysis of high-resolution (R ∼ 22,500) H-band spectra from the
SDSS-IV–APOGEE survey. Chemical abundances of 13 elements—C,
O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, and Fe—are extracted from
the APOGEE spectra of these early M-dwarfs via spectrum syntheses
computed with an improved line list that takes into account
H2O and FeH lines. This paper demonstrates that APOGEE
spectra can be analyzed to determine detailed chemical compositions of
M-dwarfs. Both exoplanet-hosting M-dwarfs display modest sub-solar
metallicities: [Fe/H]Kepler-138 = ‑0.09 ± 0.09
dex and [Fe/H]Kepler-186 = ‑0.08 ± 0.10 dex. The
measured metallicities resulting from this high-resolution analysis are
found to be higher by ∼0.1–0.2 dex than previous estimates
from lower-resolution spectra. The C/O ratios obtained for the two
planet-hosting stars are near-solar, with values of 0.55 ± 0.10
for Kepler-138 and 0.52 ± 0.12 for Kepler-186. Kepler-186
exhibits a marginally enhanced [Si/Fe] ratio.
Related projects
Traces of Galaxy Formation: Stellar populations, Dynamics and Morphology
We are a large, diverse, and very active research group aiming to provide a comprehensive picture for the formation of galaxies in the Universe. Rooted in detailed stellar population analysis, we are constantly exploring and developing new tools and ideas to understand how galaxies came to be what we now observe.
Ignacio
Martín Navarro
Nucleosynthesis and molecular processes in the late stages of Stellar Evolution
Low- to intermediate-mass (M < 8 solar masses, Ms) stars represent the majority of stars in the Cosmos. They finish their lives on the Asymptotic Giant Branch (AGB) - just before they form planetary nebulae (PNe) - where they experience complex nucleosynthetic and molecular processes. AGB stars are important contributors to the enrichment of the
Domingo Aníbal
García Hernández
Chemical Abundances in Stars
Stellar spectroscopy allows us to determine the properties and chemical compositions of stars. From this information for stars of different ages in the Milky Way, it is possible to reconstruct the chemical evolution of the Galaxy, as well as the origin of the elements heavier than boron, created mainly in stellar interiors. It is also possible to
Carlos
Allende Prieto