Atmospheric Turbulence Characteristics Inferred from Optical Measurements at Lick Observatory

摘要

This thesis used images of stars and wavefront sensor measurements taken at Lick Observatory on Mt. Hamilton, California by the Laser Guide Star Project of Lawrence Livermore National Laboratory over the period from February, 1993 to March, 1995. The observations were a part of the development of an adaptive optics system to be used on the Shane 120 inch telescope at Lick. Speckle images were made with a CCD camera operating with a fast shutter. For wavefront measurements, a tip-tilt tracking and control loop was used to correct for tip-tilt at a point in the optical train ahead of a Shack-Hartmann lenslet array. The latter measured slopes of the tip-tilt corrected wavefront at each subaperture. Output from the wavefront sensor was used for wavefront reconstruction and subsequent driving of a deformable mirror. Long exposure images were interleaved with wavefront measurements using the same CCD camera used for speckle imaging.