-- AaronAndrews - 25 Oct 2016

To do by Friday:

  • Anisha:
    • Fit sqrt(sigma0^2 + lambda*t) to the fitted standard deviation as a function of exposure time plot
  • Aaron:
    • Simulate background.
    • Generate stars in fiducial volume around frame.
    • Generate full size star field (1530x1020), use uniform randomised values for all star variables (positions, fluxes, sigmas, correlation).
  • Laura:
    • Fix star-finding code, attempt to calculate flux for each star
Weekly Progress:

Anisha:

* Histogram of a dark frame 0.1s exposure:
HistogramForDarkFrame0.1Exposure.png

  • The fitted mean and fitted sigma as a function of exposure time:
    MeanAndSigmaAsAFunctionOfExposureTime.png

  • The mean as a function of exposure time is linearly fitted with nu_0 + mu*t
  • Parameters obtained:
  • Nu0: 917.858645977
  • Mu: 0.0759400473796
  • The sigma as a function of exposure time is fitted with sqrt(sigma0^2 + lambda*t)
  • Parameters obtained:
  • Lambda: 0.0364088264173
  • Sigma0: 6.44315650804

Aaron:

  • Simulation code: Simulation_test6.py.txt
  • Added generation of background to simulation. Assumed background values follow gaussian distribution - Python has a random gaussian generator with mean and S.D. as inputs.
  • Stars can be generated outside of image frame (up to 15 pixels from edge).
  • Randomly generated star parameters can be saved in text files.

  • Generated a full-size star field, making estimates for some values/ranges for a 10 second exposure, and maximum signal/background ~2.
  • Properties:
    • Size: 1530x1020
    • Stars in frame: 50
    • Background mean: 918.23
    • Background S.D.: 23.06
  • Random parameter ranges (uniformly distributed):
    • Peak x position: [-15,1544]
    • Peak y position: [-15,1034]
    • Sigma_x: [3,6]
    • Sigma_y: [3,6]
    • Rho: [-0.5,0.5]
    • Peak value: [0,2000]
  • RandStarField1a.png
  • Star parameters: RandStarField1a.txt
  • Alternative generation, estimating 300 second exposure, maximum s/b~60:
    • Background mean: 941.43
    • Background S.D.: 234.76
    • Peak value range: [0,60000]
  • RandStarField1b.png
  • Star Parameters: RandStarField1b.txt
Laura:
  • Code: StarFinder.txt
  • Program now stores all coordinates in a star, mean pixel values (count) of the star used to calculate star flux
Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng FittedMeanAsAFunctionOfExposureTime.png r1 manage 36.1 K 28 Oct 2016 - 13:25 AnishaVadher Fitted mean as a function of exposure time
PNGpng HistogramForDarkFrame0.1Exposure.png r1 manage 30.8 K 28 Oct 2016 - 13:22 AnishaVadher Histogram of a dark frame 0.1s exposure
PNGpng MeanAndSigmaAsAFunctionOfExposureTime.png r1 manage 59.3 K 28 Oct 2016 - 13:39 AnishaVadher The fitted mean and fitted sigma as a function of exposure time
PNGpng RandStarField1a.png r3 r2 r1 manage 474.6 K 28 Oct 2016 - 12:34 AaronAndrews Random star field simulation, estimating 10 second exposure
Texttxt RandStarField1a.txt r1 manage 5.4 K 27 Oct 2016 - 09:56 AaronAndrews Generated star parameters for random star field 1a
PNGpng RandStarField1b.png r3 r2 r1 manage 353.0 K 28 Oct 2016 - 12:35 AaronAndrews Random star field simulation, estimating 300 second exposure
Texttxt RandStarField1b.txt r1 manage 5.4 K 27 Oct 2016 - 09:57 AaronAndrews Generated star parameters for random star field 1b
Texttxt Simulation_test6.py.txt r1 manage 10.9 K 27 Oct 2016 - 09:53 AaronAndrews Simulation test 6 code
Texttxt StarFinder.txt r1 manage 2.9 K 28 Oct 2016 - 11:49 LauraBevilacqua Star finding code
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Topic revision: r6 - 28 Oct 2016 - AnishaVadher

 
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