TO DO list after the meeting of the 12th of October 2006

(present: , S. Adkins, D. Gavel, S. Thomas)

GOALS: Determine the sampling and the size of the subaperture needed, considering both the open and closed loop.

• Validation of some simulation parameters
  • Validation of the noise simulation
  • Check the optimum number of iterations
• Develop the piece of code to simulate the elongated spot obtained from a Sodium layer.
  • Get the profile Pa (from Luc and Don) + photon noise
  • Check that the speckle introduced by the atmosphere is negligible (DG)
  • If b true, simply simulate the propagation through the atmosphere by using the atmosphere PSF in closed loop and a tilt statistic in open loop
  • Simulate diffraction pattern
  • Add readout noise and background
  • Add time variations
• Simulate the elongation
  • We know the altitude (with a precision of 100m which is fine) and the thickness -> We can get the elongation for the different subapertures.
• For the correlation method and the Weighted Center of Gravity, change the reference image.
  • Use a Gaussian
  • Use the same image as the one used to create the image
  • Use an average over time of real images
• Add Luc and Brent matched filter to the collection of centroiding algorithms.
• Get the curve variance vs sampling for the different reference functions (and for different elongation?)
• Parameters:
  • Sampling: FWHM = [0.5 - 3] pixels
  • Readout noise: [0 - 4] electrons
  • Photon number such that SNR > 10
• Open-loop
  • How many pixels do we need to add to account for the atmospheric tilt
  • What are the centroid offset needed due to non-common path errors
• Pulsed laser: Advantages? Change progressively the size of the elongation ratio.

Milestone next month: 13th or 14th of November

-- SandrineThomas - 13 Oct 2006