The Gemini NICI Planet-Finding Campaign: Planet Frequency for Young Moving Group Stars

We report results of a direct imaging survey for giant planets of a sample of 79 young FGK stars which are members of the β Pic, TW Hya, AB Dor, Tucana-Horologium, or Hercules-Lyra moving groups and were observed as part of the Gemini-NICI Planet Finding Campaign. For this sample, we obtained median contrasts of Δ(mag)=14.0 mag at 1'' in in combined ADI+SDI mode. We found numerous candidate companions in our survey images. The vast majority of these candidates were eliminated as background objects either from archival observations or NICI followup. However, four co-moving brown dwarf or stellar companions were discovered in the moving group sample, including PZ Tel B and CD -35 2722B. From a Bayesian analysis for a wide range of parameters and power-law models of planet distributions, we restrict the planet frequency for 1-20 M_{Jup} objects at semi-major axes from 10-150 AU to <10.5% or less at a 98% confidence level. This survey is the deepest search to date for giant planets around young Moving Group stars.