The Gemini NICI Planet-Finding Campaign

Abstract

Our team is carrying out a multi-year observing program to directly image and characterize young extrasolar planets using the Near-Infrared Coronagraphic Imager (NICI) on the Gemini-South 8.1-meter telescope. NICI is the first instrument on a large telescope designed from the outset for high-contrast imaging, comprising a high-performance curvature adaptive optics (AO) system with a simultaneous dual-channel coronagraphic imager. Combined with state-of-the-art AO observing methods and data processing, NICI typically achieves ≈2 magnitudes better contrast compared to previous ground-based or space-based planet-finding efforts, at separations inside of ≈2 ′′ . In preparation for the Campaign, we carried out efforts to identify previously unrecognized young stars as targets, to develop a rigorous quantitative method for constructing our observing strategy, and to optimize the combination of angular differential imaging and spectral differential imaging. The Planet-Finding Campaign is in its second year, with first-epoch imaging of 174 stars already obtained out of a total sample of 300 stars. We describe the Campaign's goals, design, target selection, implementation, on-sky performance, and preliminary results. The NICI Planet-Finding Campaign represents the largest and most sensitive imaging survey to date for massive ( ∼ >1 M Jup ) planets around other stars. Upon completion, the Campaign will establish the best measurements to date on the properties of young gas-giant planets at ∼ >5-10 AU separations. Finally, Campaign discoveries will be well-suited to long-term orbital monitoring and detailed spectrophotometric followup with next-generation planet-finding instruments.Keywords: Extrasolar planets; brown dwarfs; high contrast imaging; adaptive optics; near-IR instrumentation.Email: mliu@ifa.hawaii.edu Figure 1. Left: NICI at Mauna Kea Infrared in Hilo, Hawaii, prior to acceptance testing. Right: Block diagram of NICI optical configuration, including the 85-element curvature AO system, the focal & pupil plane mask mechanisms, and the two IR imaging channels. NICI is the first imager for a 8-10 meter telescope designed expressly for exoplanet imaging and is now in routine operation at the Gemini-South 8.1-meter Telescope.

A New High Contrast Imaging Program at Palomar Observatory

“…Direct imaging surveys (e.g., Masciadri et al 2005;Biller et al 2007;Lafrenière et al 2007a;Nielsen et al 2008;Carson et al 2009;Chauvin et al 2010;Leconte et al 2010;Liu et al 2010) hold the promise of quickly settling some of the most basic puzzles about exoplanetary systems, such as the true fraction of stars hosting planets, the dependence of this fraction on stellar environment, and a more robust measure of multiplicity in exoplanetary systems. Future surveys can also quickly assess the distribution of planets beyond 5-10 AU.…”