This award is in support of the Gemini NICI Planet-Finding Campaign. Dr. Liu and collaborators will be conducting the largest and most sensitive direct imaging survey to date for massive (>1 Jupiter Mass) planets orbiting other stars. NICI (the Near-Infrared Coronagraphic Imager) is the new high contrast adaptive optics camera on the Gemini-South 8.1-meter telescope, tailored to direct detection of extrasolar planets through dual-channel methane-band imaging. NICI is expected to provide excellent sensitivity to planetary companions around young (< 100 million years) stars in the extended solar neighborhood.
In addition to providing images of the planets themselves, three specific issues in extrasolar planet formation are expected to be addressed through this work: 1) the distribution of planets in the outer (> 5-10 AU) regions of other solar systems, 2) the dependence of planet frequency on stellar host mass, and 3) the spectrophotometric properties of young extrasolar planets. Target selection will be optimized through Monte Carlo simulations and it is expected that several giant planets will be detected among the 150 young stars to be surveyed.
The research goals of this project will be accomplished in tandem with the training of a postdoctoral research associate at all stages of the project. This next generation of scientists will receive training in the rapidly growing fields of exoplanets and science with adaptive optics, as well as hands-on experience with real-time observing on an 8-meter telescope. In particular, development of observational techniques and expertise with high contrast adaptive optics systems is an important step toward future high angular resolution ground-based astronomy. Undergraduate students are also expected to be involved in the work through the Institute for Astronmy's ongoing NSF Research Experiences for Undergraduates program. Dr. Liu will also continue to participate in ongoing outreach efforts through public lectures and discussions, where this research and the results will be prominently featured.
One of the most exciting astronomical developments in the past 15 yearshas been the discovery and characterization of extrasolar planets ---planets in orbit around stars other than our Sun, a.k.a. "exoplanets".Direct detection of gas-giant exoplanets is now becoming possible,opening the door to new avenues of understanding distinct from radialvelocity and transit detections. We have completed an unprecedented250-star high-contrast imaging campaign to detect and characterize young(<~1 Gyr) extrasolar planets and brown dwarfs using the Near-InfraredCoronagraphic Imager (NICI) on the Gemini-South 8.1-meter telescope. NICI is the first instrument designed from the outset for high-contrastimaging on a large telescope, comprising a high-performance adaptiveoptics (AO) system with a simultaneous dual-channel coronagraphicimager. In combination with state-of-the-art AO observing and dataanalysis, the NICI Campaign achieves about 2 magnitudes better contrastcompared to any previous ground-based or space-based planet-findingefforts inside of ~2 arcsec separations. Overall, the NICIPlanet-Finding Campaign represents the largest and most sensitiveimaging survey to date for brown dwarfs and Jovian-mass planets aroundother stars. To date, the NICI Campaign has discovered three new substellar (~30Mjup) companions to young stars. These objects will be prime targets forfuture photometric and spectroscopic followup to understand theirproperties. More broadly, our final goal is to quantify the mass andseparation distributions of outer (>~5–10 AU) planets with this largehomegenous dataset, since the physics behind planet formation is encodedin these quantities.
