Two jupiter-mass planets orbiting HD 154672 and HD 205739

Abstract

We report the detection of the first two planets from the N2K Doppler planet search program at the Magellan telescopes. The first planet has a mass of Msin i = 4.96 M Jup and orbits the G3 IV star HD 154672 with an orbital period of 163.9 days. The second planet orbits the F7 V star HD 205739 with an orbital period of 279.8 days and has a mass of Msin i = 1.37 M Jup. Both planets are in eccentric orbits, with eccentricities e = 0.61 and e = 0.27, respectively. Both stars are metal rich and appear to be chromospherically inactive, based on inspection of their Ca II H and K lines. Finally, the best Keplerian model fit to HD 205739b shows a trend of 0.0649 m s-1 day-1, suggesting the presence of an additional outer body in that system. © 2008. The American Astronomical Society. All rights reserved.