Data analysis

  • Below are some examples for Guassian fitted histograms of pixel ADU values at different exposure times. Plotting the y-axis (frequency of pixels with a given ADU value) logarithmically allows for easier identification of high value pixels that are currently influencing the fit.
log-10c_0000.1s1.png
  • -10c_0000.1s: mu=945.979, simga=4.934
log-10c_0001s1.png
  • -10c_0001s: mu=946.100, sigma=4.927
log-10c_0010s1.png
  • -10c_0010s: mu=946.536, sigma=4.984
On can see obvious bin entries at larges ADU values (accidentally displayed incorrectly as number of photoelectrons!).

Goals:

  • understand scale of y-axis
  • Now extreme value pixels have been identified, I shall aim to exclude these from the Gaussian fit as they are currently skewing results.
  • To obtain more accurate plots of mu v t and sigma v t, I shall aim to find the mean values at a given exposure time averaging over 10 exposures for exposures up to (and including) 100s and over 5 exposures for exposures between 150s-1200s. This is to be done as currently the statistical error in the mu values is ~10^(-6) the size of each mu value.

Observation targets

Will be looking to add to and narrow down in near future.

Target m ~dimensions (')

~age (Ma)

M45 1.6 110 150
M38 7.4 21 290
M36 6.3 12 25
M37 6.2 24 500
M35 5.3 28 110
M41 4.5 38 190
M50 5.9 16 78
M47 4.2 30 78
M46 6.1 27 300
M93 6 22 100
M48 5.5 54 300
M44 3.7 95 600
M67 6.1 30 3200-5000!
Topic attachments
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PowerPointpptx 25_10_2018.pptx r1 manage 5993.3 K 25 Oct 2018 - 14:00 AriannaSaba  
PNGpng log-10c_0000.1s1.png r1 manage 32.5 K 25 Oct 2018 - 14:07 JacobChambers  
PNGpng log-10c_0001s1.png r1 manage 32.6 K 25 Oct 2018 - 14:13 JacobChambers  
PNGpng log-10c_0010s1.png r1 manage 32.5 K 25 Oct 2018 - 14:13 JacobChambers  
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Topic revision: r2 - 25 Oct 2018 - JacobChambers

 
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