Lucky Exposures: Diffraction limited astronomical imaging through the atmosphere

Ph.D. Thesis Dissertation by Robert Nigel Tubbs

Cambridge University, UK

September 2003

PDF version of thesis dissertation with full quality figures

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• http://www.strw.leidenuniv.nl/~tubbs/thesis/rnt_thesis.pdf - PDF version of thesis dissertation (18 MB)
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• rnt_thesis.zip - zipped version of the same PDF file, compatible with PKZIP and LINUX zip (8 MB)
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Lower quality versions of individual chapters with smaller PDF file sizes can be downloaded from the HTML version of the thesis below.

HTML version of thesis (with low quality figures and small file sizes)

Note that many figures are poorly reproduced in the HTML version of the document. To view a full quality document, download one of the PDF versions listed above

Contents

• Front Matter from thesis
  
• Introduction (also available as a low quality version in PDF format - 600kB)
  • The need for high resolution optical imaging
  • Short exposure optical imaging through the atmosphere
    • The Kolmogorov model of turbulence
    • Example short exposure images
    • Exposure selection
  • Performance of ground-based high resolution imaging techniques
    • Limiting magnitude of reference source
    • Isoplanatic patch
    • Sensitivity to faint objects
    • Cost and complexity of implementation
    • Comparison of imaging techniques
  • Summary of thesis
  
  
• Lucky Exposures (also available as a low quality version in PDF format - 400kB)
  • Introduction
  • Timescale measurements by previous authors
    • Normalising the short-timescale component of the autocorrelation
    • The temporal power spectrum of intensity fluctuations
  • Timescale measurements for atmospheric simulations
    • Atmospheric models
    • Single Taylor screen model
    • Numerical simulations
  • Isoplanatic angle for atmospheric simulations
  • Exposure selection from simulated data
  • Conclusions
  
  
• Observations of bright sources at the NOT (also available as a low quality version in PDF format - 2MB)
  • Introduction
  • Experimental method
    • Background
    • The effect of mirror aberrations
    • Observations
  • Data reduction method
    • Application to observational data
    • Exposure selection
  • Observational results with single stars
    • Exposure selection results
    • Temporal properties of the atmosphere
    • Timescales for exposure selection
  • Results with binary stars
    • Data taken on zeta Bootis
    • Varying the fraction of exposures selected
    • Strehl ratios obtained for Boötis
    • Resolution and spatial frequency response
    • Weighting exposures
    • Anisoplanatism
    • Temporal and spatial cross correlation
    • Atmospheric dispersion and Delphini
    • Dynamic range
    • Seeing conditions
  • Conclusions
  
  
• Electron multiplying CCD performance (also available as a low quality version in PDF format - 800kB)
  • Introduction
  • Simple models of the L3Vision CCDs
    • L3Vision CCD architecture
    • Model descriptions
    • Statistics of a single gain stage
    • Statistical properties of registers with multiple stages
    • Signal-to-noise performance
    • Calculating the probability distribution for the output electrons
    • Results from numerical simulations
  • CCD measurements
    • Example data from observations at the NOT
    • Charge transfer efficiency problems with the camera
  • Conclusions
  
  
• Observations with a low noise CCD at the NOT (also available as a low quality version in PDF format - 2MB)
  • Introduction
  • Aims
  • Observations
    • Filters and bandpasses
    • Observations in July 2001
    • Observations in July 2002
    • Observations in June-July 2003
  • Data reduction
    • Fourier filtering
    • Performance of the Fourier filtering
  • Results
    • Results of exposure selection
    • Isoplanatic angle
    • Limiting magnitude of reference star
    • Assessment of image quality
    • Dynamic range
  • Sky coverage
  • Conclusions
  
  
• Conclusions (also available as a low quality version in PDF format - 50kB)
• Simplified approximation to a single Taylor screen atmosphere (also available as a low quality version in PDF format - 100kB)
• Observation log for June-July 2003 observations at the NOT (also available as a low quality version in PDF format - 60kB)
• Bibliography (also available as a low quality version in PDF format - 110kB)
• About this document ...

Related links

• Lucky Exposures website from the COAST Group, Cambridge University
• A little background information on Lucky Exposures and Video Astronomy