Adaptive Optics at the Institute for AstronomyThe Adaptive Optics Laboratory at the Institute for Astronomy (IfA), led by Mark Chun and Christoph Baranec, develop innovative technologies and systems that counteract the image-blurring effect of Earth's atmosphere. The ‘imaka project, led by Chun, is working toward extremely large corrected fields of view at visible and near-infrared wavelengths. By correcting for the atmosphere just close to the telescope, the team has demonstrated corrected fields of view larger than previously thought possible. Robo-AO, led by Baranec, is a fully robotic system that can observe hundreds of objects per night at near Hubble Space Telescope resolution. Don Hall develops new photon-counting near-infrared detectors that are used in several adaptive optics systems: Robo-AO, the pyramid wavefront sensor for Keck, and with SCExAO at Subaru.
Current Adaptive Optics Projects
`Imaka is an instrument concept for an extremely wide-field ground-layer adaptive optics on Maunakea, Hawaii. The instrument leverages Maunakea’s unique conditions: excellent seeing, weak free-atmosphere seeing, and its highly-confined boundary layer turbulence with a ground-layer adaptive optics system to deliver high-resolution images over fields of view of several tens of arcminutes. The `imaka instrument on the UH2.2-meter telescope provides some of the finest wide-field images ever obtained from the ground over a field of view nearly an order of magnitude larger than other sites. The project is aptly named after the Hawaiian word `imaka meaning “scenic viewpoint”.
Wavefront sensing in the infrared is highly desirable for the study of M-type stars and cool red objects, as they are sufficiently bright in the infrared to be used as the adaptive optics guide star. This aids in high contrast imaging, particularly for low mass stars where the star-to-planet brightness ratio is reduced. The combination of infrared detector technology with the highly sensitive Pyramid wavefront sensor (WFS) can extend the capabilities of current telescopes and meet the requirements for future instruments, such as those proposed for the giant segmented mirror telescopes. We are building a new infrared Pyramid WFS for Keck, a key sub-system of the Keck Planet Imager and Characterizer (KPIC) that will take advantage of the combination. The Keck infrared pyramid wavefront sensor project is lead at IfA by Charlotte Bond.
Don Hall has worked with Leonardo (formerly Selex) to develop and characterize the SAPHIRA infrared avalanche photo-diode (APD) arrays including implementing a traveling test camera. This camera has been demonstrated on-sky for imaging at the IRTF telescope, for tip-tilt sensing and science with the Robo-AO system, and for speckle imaging with the Subaru SCExAO system. UH will be implementing faster readout electronics suitable for high order AO wavefront sensing.
People Working at the Lab
- Charlotte Bond
- Dora Fohring
IfA Graduate Students
- Max Service
- Maisa Salama
- Ryan Dungee
- James Ou