Cool Stars 14 - Submitted Abstract # 316
This version created on 05 October 2006

Metallicities and Planet Formation


Jeff Valenti, STScI
Debra Fischer, SFSU

Spectroscopic analysis of stars with and without known planets
constrains models of giant planet formation.  Multiple studies have
demonstrated conclusively that higher metallicity stars are much more
likely to have giant planets that are detectable by current radial
velocity surveys.  The enhanced metallicity of stars with planets does
not depend significantly on whether the convection zone is shallow (F
dwarfs) or deep (K dwarfs, subgiants), so the metallicity enhancement
is not caused by accretion of rocky debris.  The metallicity
distribution of stars with known planets does not depend significantly
on orbital period, so there is no evidence that the metallicity
enhancement is caused by planetary migration.  The current hypothesis
is that high metallicity in a protoplanetary disk enhances planet core
formation and subsequent envelope accretion.  

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