Testing the Planet-Metallicity Correlation in M-dwarfs with Gemini GNIRS Spectra

HOBSON, M; JOFRÉ, E.; GARCÍA, L.; PETRUCCI, R.; GOMEZ, M.

REVISTA MEXICANA DE ASTRONOMíA Y ASTROFíSICA

UNIV NACIONAL AUTONOMA MEXICO

Lugar: México; Año: 2018

0185-1101

While the planet-metallicity correlation for FGK main-sequence stars hosting giant planets is well established, it is less clear for M-dwarf stars. We determine stellar parameters and metallicities for 16 M-dwarf stars, 11 of which host planets, with near-infrared spectra from the Gemini Near-Infrared Spectrograph (GNIRS). We find that M-dwarfs with planets are preferentially metal-rich compared to those without planets. This result is supported by the analysis of a larger catalogue of 18 M stars with planets and 213 M stars without known planets T15, and demonstrates the utility of GNIRS spectra to obtain reliable stellar parameters of M stars. We also find that M dwarfs with giant planets are preferentially more metallic than those with low-mass planets, in agreement with previous results for solar-type stars. These results favor the core accretion model of planetary formation.