Carbon abundance of stars in the LAMOST-Kepler field

Abstract

The correlation between host star iron abundance and the exoplanet occurrence rate is well-established and arrived at in several studies. Similar correlations may be present for the most abundant elements, such as carbon and oxygen, which also control the dust chemistry of the protoplanetary disk. In this paper, using a large number of stars in the Kepler field observed by the LAMOST survey, it has been possible to estimate the planet occurrence rate with respect to the host star carbon abundance. Carbon abundances are derived using synthetic spectra fit of the CH G-band region in the LAMOST spectra. The carbon abundance trend with metallicity is consistent with the previous studies and follows the Galactic chemical evolution (GCE). Similar to [Fe/H], we find that the [C/H] values are higher among giant planet hosts. The trend between [C/Fe] and [Fe/H] in planet hosts and single stars is similar; however, there is a preference for giant planets around host stars with a sub-solar [C/Fe] ratio and higher [Fe/H]. Higher metallicity and sub-solar [C/Fe] values are found among younger stars as a result of GCE. Hence, based on the current sample, it is difficult to interpret the results as a consequence of GCE or due to planet formation.

arXiv commentAccepted for publication in The Astronomical Journal

References in corpus (46)

• Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler
• Spectroscopic [Fe/H] for 98 extra-solar planet-host stars: Exploring the probability of planet formation
• The NASA Exoplanet Archive: Data and Tools for Exoplanet Research
• Giant Planet Occurrence in the Stellar Mass-Metallicity Plane
• Spectroscopic parameters for 451 stars in the HARPS GTO planet search program. Stellar [Fe/H] and the frequency of exo-Neptunes
• Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program.Galactic stellar populations and planets
• The SEGUE Stellar Parameter Pipeline. I. Description and Initial Validation Tests
• The metal-rich nature of stars with planets
• C/O ratio as a Dimension for Characterizing Exoplanetary Atmospheres
• The peculiar solar composition and its possible relation to planet formation
• Terrestrial Planet Occurrence Rates for the Kepler GK Dwarf Sample
• The California-Kepler Survey. IV. Metal-rich Stars Host a Greater Diversity of Planets
• Revised Radii of Kepler Stars and Planets Using Gaia Data Release 2
• The Compositional Diversity of Extrasolar Terrestrial Planets: I. In-Situ Simulations
• Revised Stellar Properties of Kepler Targets for the Q1-17 (DR25) Transit Detection Run
• The Exoplanet Census: A General Method, Applied to Kepler
• Enhanced lithium depletion in Sun-like stars with orbiting planets
• Chemical Clues on the Formation of Planetary Systems: C/O vs Mg/Si for HARPS GTO Sample
• The remarkable solar twin HIP 56948: a prime target in the quest for other Earths
• Chemical abundances of 451 stars from the HARPS GTO planet search program: Thin disc, thick disc, and planets
• The Age of the Solar Neighbourhood
• Li abundances in F stars: planets, rotation and galactic evolution
• Carbon-Enhanced Metal-Poor Stars in the Inner and Outer Halo Components of the Milky Way
• Searching for the signatures of terrestial planets in solar analogs
• Searching for the signatures of terrestrial planets in F-, G-type main-sequence stars
• Li depletion in solar analogues with exoplanets: Extending the sample
• Exploring the alpha-enhancement of metal-poor planet-hosting stars. The Kepler and HARPS samples
• Overabundance of alpha-elements in exoplanet host stars
• Hot Jupiters are Destroyed by Tides While Their Host Stars are on the Main Sequence
• An accurate and self-consistent chemical abundance catalogue for the APOGEE/Kepler sample
• C, S, Zn and Cu abundances in planet-harbouring stars
• On the origin of stars with and without planets. Tc trends and clues to Galactic evolution
• A Super-Solar Metallicity For Stars With Hot Rocky Exoplanets
• Kepler Exoplanet Candidate Host Stars are Preferentially Metal Rich
• Properties and occurrence rates of $Kepler$ exoplanet candidates as a function of host star metallicity from the DR25 catalog
• LAMOST observations in the Kepler field. II. Database of the low-resolution spectra from the five-year regular survey
• Spectral Properties of Cool Stars: Extended Abundance Analysis of Kepler Objects of Interest
• Parent Stars of Extrasolar Planets. XI. Trends with Condensation Temperature Revisited
• Analysis of membership probability in nearby young moving groups with Gaia DR2
• CNO behaviour in planet-harbouring stars. II. Carbon abundances in stars with and without planets using the CH band
• Parent Stars of Extrasolar Planets - XIV. Strong Evidence of Li Abundance Deficit
• Host star metallicity of directly imaged wide-orbit planets: implications for planet formation
• Behaviour of elements from lithium to europium in stars with and without planets
• Exoplanet hosts reveal lithium depletion: Results from a homogeneous statistical analysis
• Galactic chemical evolution of exoplanet host stars: Are high-mass planetary systems young?
• Kinematics of Vega-like stars: lifetimes and temporal evolution of circumstellar dust disks

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• The Gaia spectroscopic catalogue of exoplanets and host stars
• Chemical composition of planetary hosts: C, N, and $\alpha$-element abundances
• Caveats about measuring carbon abundances in stars using the CH band