Exoplanet host stars are rich in alpha-elements

Overabundance of α-elements in exoplanet host stars

Investigation of the metallicity of exoplanet host stars for elements other than iron. Seems to be a particularly strong correlation for magnesium.

Now adding the Kepler candidates as well as the HARPS sample. The results suggest that early planet formation could happen in the galaxy's thick disc where the chemical conditions (alpha-enhancement) would be more favourable.

Exploring the α-enhancement of metal-poor planet-hosting stars. The Kepler + HARPS samples