Long-Period Objects in the Extrasolar Planetary Systems 47 Ursae Majoris and 14 Herculis*

摘要: The possible existence of additional long-period planetary-mass objects in the extrasolar planetary systems 47 UMa and 14 Her is investigated. We combine all available radial velocity data on these stars, spanning up to 18 yr. For system, we show that while a second planet improves fit data, there still substantial ambiguity as orbital parameters proposed companion c. also present new observations clearly support system. With period 6906 ± 70 days, c may be 4 : 1 resonance with inner planet. revised solutions for seven previously known planets, incorporating recent obtained 2.7 m Harlan J. Smith Telescope at McDonald Observatory.