Physical Sciences and Mathematics Commons^™

Five New Multicomponent Planetary Systems, Steve Vogt, R. Paul Butler, Geoffrey W. Marcy, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, Jason T. Wright, John A. Johnson

Information Systems and Engineering Management Research Publications

We report Doppler measurements for six nearby G- and K-type main-sequence stars that show multiple low-mass companions, at least one of which has planetary mass. One system has three planets, the fourth triple-planet system known around a normal star, and another has an extremely low minimum mass of 18 M⊕. HD 128311 (K0 V) has two planets (one previously known) with minimum masses (M sin i) of 2.18MJ and 3.21MJ and orbital periods of 1.26 and 2.54 yr, suggesting a possible 2 : 1 resonance. For HD 108874 (G5 V), the velocities reveal two planets (one previously known) having minimum …