Resolution limits for ground based astronomical imaging using adaptive optics

Details Resolution limits for ground based astronomical imaging using adaptive optics Resolution limits for ground based astronomical imaging using adaptive optics

Mar 1992

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1992lgsa.workr..10o&link_type=abstract

Presented at the Laser Guide Star Adaptive Optics Workshop, Albuquerque, NM, 10-12 Mar. 1992

Physics

Optics

Adaptive Optics, Astronomy, Image Processing, Images, Imaging Techniques, Optical Correction Procedure, Telescopes, Apertures, Atmospheric Effects, Atmospheric Turbulence, Earth Atmosphere, Feedback Control, Mirrors, Steering, Vibration

Scientific paper

We study the residual jitter present in astronomical images after the effect of the earth's atmosphere has been compensated using a fast steering mirror. This residual jitter places a limit on the resolution that can be achieved for long exposure images even when more elaborate adaptive optics systems are used to correct the image. We assume that the fast guiding system uses a star as its reference source. Then, from the observed characteristics of galactic stellar populations, we are able to predict the optimal performance of the fast guiding system as a function of the sky covering factor: that is the fraction of the sky for which the given level of performance can be achieved. The performance for a particular sky covering factor is optimized by choosing the appropriate closed-loop bandwidth and guide star magnitude. The performance also depends on a number of atmospheric and system parameters; however, we find that the optimal performance is relatively insensitive to all but two of these parameters, the telescope aperture size, and the strength of the atmospheric turbulence. Therefore, we consider two specific examples: first, a ten meter telescope imaging an atmosphere with relatively weak turbulence (3/4 arcsecond seeing in V), and second, a one meter telescope imaging through an atmosphere with relatively strong turbulence (2 arcsecond seeing in V). For these cases we find, for example, that a residual jitter of less than 0.03 and 0.3 arcseconds respectively can be obtained over about half the sky for nominal choices of the other parameters. The required closed-loop bandwidths in these cases are about 5 and 20 Hz while the appropriate guide stars are approximately 18th and 14th magnitude in V.

Affiliated with

Also associated with

No associations

Rating

Resolution limits for ground based astronomical imaging using adaptive optics does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Resolution limits for ground based astronomical imaging using adaptive optics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Resolution limits for ground based astronomical imaging using adaptive optics will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1219125