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The results of new spectroscopic analyses of 30 stars with giant planet and/or brown dwarf companions are presented. Values for T eff 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 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.

We have searched for optical coronal lines in the 3100-3700 A ˚region of eight M dwarf stars with rather low levels of activity. This brief survey supplements a similar search in 15 active stars published in 1991. No coronal lines could be identified. However, the emission spectra including lines of H i, He i, Ca ii, Ca i, Si i, and Fe i are described and illustrated. Radial velocities of the emission lines show no systematic differences from the stellar absorption lines. Coronae with temperatures similar to those in the solar corona seem to be rare among the M dwarfs, although at least one example has been found by Schmitt & Wichmann.