Two Jupiter-Mass Planets Orbiting HD 154672 and HD 205739

TL;DR

This paper reports the discovery of two Jupiter-mass exoplanets orbiting stars HD 154672 and HD 205739, with detailed orbital parameters and evidence suggesting a possible additional body in one system.

Contribution

First detection of two Jupiter-mass planets from the N2K Doppler survey, providing new data on exoplanet characteristics and system dynamics.

Findings

Both planets are in eccentric orbits.

Stars are metal-rich and chromospherically inactive.

Potential additional outer body in the HD 205739 system.

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 M sin i = 4.96 M_Jup and is orbiting the G3 IV star HD154672 with an orbital period of 163.9 days. The second planet is orbiting the F7 V star HD205739 with an orbital period of 279.8 days and has a mass of M sin 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 HD205739b shows a trend of 0.0649 m/s/day, suggesting the presence of an additional outer body in that system.