Abundances of Refractory Elements for G-type Stars with Extrasolar Planets

TL;DR

This study analyzes chemical abundances in G-type stars with and without exoplanets, revealing differences linked to planetary properties and metallicity, especially for refractory elements like Mn, Mg, and Ti.

Contribution

It provides new insights into the chemical signatures associated with planet-hosting stars and their relation to planetary characteristics and metallicity.

Findings

Planet-host stars have higher [Mn/Fe] ratios across all metallicities.

Metal-poor planet-host stars tend to have low-mass planets rather than gas giants.

Distinct abundance patterns correlate with planetary mass and orbital properties.

Abstract

We confirm the difference of chemical abundance between stars with and without exoplanet, as well as present the relation between chemical abundances and the physical properties of exoplanets such as planetary mass and semi-major axis of planetary orbit. We have obtained the spectra of 52 G-type stars with BOES (BOAO Echelle Spectrograph) and carried out the abundance analysis for 12 elements of Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Co, and Ni. We first have found that the [Mn/Fe] ratios of planet-host stars are higher than those of comparisons in the whole metallicity range, and in metal-poor stars of [Fe/H] $<$ -0.4, the abundance difference have been larger than in metal-rich samples, especially for the elements of Mg, Al, Sc, Ti, V, and Co. When examined the relation between planet properties and metallicities of planet-host stars, we have observed that planet-host stars with low-metallicity tend to bear several low-mass planets ($< M_J$) instead of a massive gas-giant planet.