The Astrophysical Journal, 720:1290–1302, 2010 September 10 doi:10.1088/0004-637X/720/2/1290 C 2010. The American Astronomical Society. All rights reserved. Printed in the U.S.A. STELLAR PARAMETERS AND METALLICITIES OF STARS HOSTING JOVIAN AND NEPTUNIAN MASS PLANETS: A POSSIBLE DEPENDENCE OF PLANETARY MASS ON METALLICITY∗ L. Ghezzi1, K. Cunha1,2,3,V.V.Smith2,F.X.deAraujo´ 1,4, S. C. Schuler2, and R. de la Reza1 1 Observatorio´ Nacional, Rua General Jose´ Cristino, 77, 20921-400, Sao˜ Cristov´ ao,˜ Rio de Janeiro, RJ, Brazil;
[email protected] 2 National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719, USA 3 Steward Observatory, University of Arizona, Tucson, AZ 85121, USA Received 2010 May 12; accepted 2010 July 15; published 2010 August 19 ABSTRACT The metal content of planet-hosting stars is an important ingredient that may affect the formation and evolution of planetary systems. Accurate stellar abundances require the determinations of reliable physical parameters, namely, the effective temperature, surface gravity, microturbulent velocity, and metallicity. This work presents the homogeneous derivation of such parameters for a large sample of stars hosting planets (N = 117), as well as a control sample of disk stars not known to harbor giant, closely orbiting planets (N = 145). Stellar parameters and iron abundances are derived from an automated analysis technique developed for this work. As previously found in the literature, the results in this study indicate that the metallicity distribution of planet-hosting stars is more metal rich by ∼0.15 dex when compared to the control sample stars.