Parent Stars of Extrasolar Planets. VII. New Abundance Analyses of 30 Systems

Chris Laws, Guillermo Gonzalez, Kyle M. Walker, Sudhi Tyagi, Jeremey Dodsworth, Keely Snider, Nicholas B. Suntzeff
2003 Astronomical Journal  
The results of new spectroscopic analyses of 30 stars with giant planet and/or brown dwarf companions are presented. Values for Teff and [Fe/H] are used in conjunction with Hipparcos data and Padova isochrones to derive masses, ages, and theoretical surface gravities. These new data are combined with spectroscopic and photometric metallicity estimates of other stars harboring planets and published samples of F, G, and K dwarfs to compare several subsets of planet bearing stars with similarly
more » ... s with similarly well-constrained control groups. The distribution of [Fe/H] values continues the trend uncovered in previous studies in that stars hosting planetary companions have a higher mean value than otherwise similar nearby stars. We also investigate the relationship between stellar mass and the presence of giant planets and find statistically marginal but suggestive evidence of a decrease in the incidence of radial velocity companions orbiting relatively less massive stars. If confirmed with larger samples, this would represent a critical constraint to both planetary formation models as well as to estimates of the distribution of planetary systems in our galaxy.
doi:10.1086/374626 fatcat:u6a2tqngrjbrzdsssyx7qg7pya