Difference: 20151009_MSciSpectrocopyAnalysis (3 vs. 4)

Revision 413 Oct 2015 - AshleaKemp

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META TOPICPARENT name="StewartBoogertSpectroscopy2015"
Spectrum
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Initially the fits file was loaded into python, the image was then projected onto the x-axis to obtain a spectrum. This was in the units of N_{adu} against position, so from the eqaution N_{pe} = 2.3*N_{adu} the data was plotted in N_{pe} against position.
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Initially the fits file was loaded into python, the image was then projected onto the x-axis to obtain a spectrum. This was in the units of N_{adu} against position, so from the eqaution N_{pe} = 2.3*N_{adu} the data was plotted in N_{pe} against position.
 
  • Cadmium_spectrum.png:
    Cadmium_spectrum.png
Background
Line: 32 to 32
 
  • Cadmium_removedBackground.png:
    Cadmium_removedBackground.png
-- JosephBayley - 13 Oct 2015
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Comparison with Unfocused Image

For Comparison, an unfocused image taken from the Cadmium lamp was analysed. As before, the fits file was loaded into python, projected onto the x axis, and then multipled by the gain, 2.3, to gain the number of photoelectrons.

Unfocused_Cadmium_Spectral_Lines.png

As you can see, the spectral lines have been broadened significantly, reducing the accuracy of locating the peaks. This shows the difference between the quality of the focused image and the unfocused image, highlighting the difference it would make to our data analysis.

Questions to ask at next meetingon 14/10/15:

  • How to fit a poisson distribution to our histograms for the background
  • How to find the exact position of the peaks.
In comparison, the background for the unfocused region is much more irregular than for the focused image.
 
META FILEATTACHMENT attachment="Cadmium_spectrum.png" attr="h" comment="" date="1444724881" name="Cadmium_spectrum.png" path="Cadmium_spectrum.png" size="74235" user="zxap044" version="1"
META FILEATTACHMENT attachment="Background_cadmium_plot.png" attr="h" comment="Background with bright pixel" date="1444735056" name="Background_cadmium_plot.png" path="Background_cadmium_plot.png" size="63206" user="zxap044" version="1"
META FILEATTACHMENT attachment="Background_cadmium_histogram.png" attr="h" comment="Background histogram" date="1444735377" name="Background_cadmium_histogram.png" path="Background_cadmium_histogram.png" size="41881" user="zxap044" version="2"
META FILEATTACHMENT attachment="Cadmium_removedBackground.png" attr="h" comment="" date="1444749862" name="Cadmium_removedBackground.png" path="Cadmium_removedBackground.png" size="89641" user="zxap044" version="1"
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META FILEATTACHMENT attachment="Unfocused_Cadmium_Spectral_Lines.png" attr="h" comment="Cadmium spectral lines - unfocused" date="1444754434" name="Unfocused_Cadmium_Spectral_Lines.png" path="Unfocused_Cadmium_Spectral_Lines.png" size="43422" user="zxap013" version="1"
META FILEATTACHMENT attachment="Unfocused_Cadmium_Background.png" attr="h" comment="" date="1444754639" name="Unfocused_Cadmium_Background.png" path="Unfocused_Cadmium_Background.png" size="60938" user="zxap013" version="1"
 
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