Sodium guide star adaptive optics system for astronomical imaging in the visible and near-infrared
- Lawrence Livermore National Lab., CA (United States)
- Science Applications International Corp., Palm Beach Gardens, FL (United States)
We are building an adaptive-optic telescope system that is based on the use of an artificial guide star created by laser-induced fluorescence of the sodium mesospheric layer. This paper discusses the system design for mid-visible to near-infrared compensation of a one meter telescope at Livermore and near-infrared compensation of the ten meter Keck telescope at Mauna Kea. We calculate the expected Strehl ratio and resolution for a 69 channel deformable mirror system and also for a possible 241 channel system upgrade. With the 69 actuator system we expect near diffraction limited resolution, about 0.2 arcsec, with a Strehl ratio of about 0.5 at [lambda]=0.8,[mu]m on the 1m telescope, and resolution of about 0.05 arcsec with a Strehl ratio of about 0.5 at [lambda]=2.0 [mu]m on the 10m telescope. Resolution will be limited by the performance of the tip/tilt correction loop, which uses an off-axis natural guide star as a reference. The effects which degrade tip/tilt correction are described in a companion paper. At Livermore, our design uses an existing high power (1 kW) laser source, which is expected to provide an approximately 6'th magnitude artificial guide star. This strong beacon signal allows a short integration time in the wavefront sensor so that temporal changes in the atmospheric turbulence can be tracked accurately. For Mauna Kea, we explore how the system to be built for the Livermore site would perform in the infrared, assuming a 100 W laser source.
- Research Organization:
- Lawrence Livermore National Lab., CA (United States)
- Sponsoring Organization:
- USDOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 6653753
- Report Number(s):
- UCRL-JC-109606; CONF-9203139-4; ON: DE93009543
- Resource Relation:
- Conference: Laser guide star adaptive optics workshop, Albuquerque, NM (United States), 10-12 Mar 1992
- Country of Publication:
- United States
- Language:
- English
Similar Records
Sodium guide star adaptive optics system for astronomical imaging in the visible and near-infrared
Sodium guide star adaptive optics system for astronomical imaging in the visible and near-infrared. Revision 1
Related Subjects
GENERAL PHYSICS
47 OTHER INSTRUMENTATION
TELESCOPES
LASER GUIDANCE
ASTRONOMY
LASER RADIATION
MESOSPHERE
NEAR INFRARED RADIATION
OPTICAL SYSTEMS
SODIUM
VISIBLE RADIATION
ALKALI METALS
EARTH ATMOSPHERE
ELECTROMAGNETIC RADIATION
ELEMENTS
INFRARED RADIATION
METALS
RADIATIONS
661320* - Auroral
Ionospheric
& Magnetospheric Phenomena- (1992-)
440600 - Optical Instrumentation- (1990-)