NExScI

NASA Exoplanet Science Institute

Serving
the
Exoplanet
Science
Community

About
 |
Conferences
 |
Sagan
Program
 |
NASA
Keck
Time
 |
Data
&
Tools
 |
Missions

Adaptive Optics Limits with the Keck Interferometer

  • Sensitivity is lower than single telescope AO due to the dichroic which sends light to the interferometer.
  • Sensitivity somewhat dependent on object color.
  • R < 12 for all V2 modes.
  • R < 10 for NULLING mode.
  • R < 14 for Dual Field Phase Referenced mode (ASTRA-DFPR).
    • See the Keck Observatory AO page for more details.
    • While the AO is locked on a star, light from a nearby offset star may be sent to the interferometer. The maximum offset is about 15 arcsec, but depends on position angle: please contact NExScI for details. The minimum offset is about 0.2 arcsec. A single component of a pair that is closer than that may be selected for interferometer measurements by adjusting the angle tracker (KAT) settings: please refer to the KAT section. Offset guiding may result in decreased observing efficiency. Offset guiding is NOT available for the NULLING mode.
    • The image rotators are used in vertical angle mode.

    Return to KI Sensitivities page
    Return to the KI Support page

    The NASA Exoplanet Science Institute is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program.