Difference: 20161104_MSciSpectroscopyMeeting (2 vs. 3)

Revision 304 Nov 2016 - WilliamBurrows

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META TOPICPARENT name="StewartBoogertSpectroscopy2016"
Peak Algorithm
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  • FWHM can be obtained by $2\sqrt{ln2}\sigma$.

  • Peak locator algorithm used for camera angle at 1.50mm:
    PeakAt1.50mm.png
Changed:
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<
Error Bars
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Error Bars and Chi Squared
 
Changed:
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  • Zoomed in look at the lowest Cd peak at 06.50mm:
    Improved_Cd_0650_Gaussians_lowest.png

  • First attempt at error bars, setting y error as sqrt of count:
    Improved_Cd_0650_Gaussians_lowest_errorbar.png
>
>
  • First attempt at error bars, setting y error as the square root of the count:
    Improved_Cd_0650_Gaussians_lowest_errorbar.png
  • Error bars are tiny due to incorrect assumption that data follows a poison distribution.
 
Added:
>
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  • Chi squared function used:
 \begin{equation} \chi2 = \sum \frac{(x_i - \mu)^2}{\sigma^2} \, . \end{equation}
  • Cd spectrum at 06.50mm with Gaussian fits, error bars and Chi squared values:
    Cd_0650_gaussian_errors_chi.png
  • Chi squared values are huge as expected due to poor fit. Once errors and fit equation are correct, Chi squared should reduce.
 -- JamesAngthopo - 03 Nov 2016

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Added:
>
>
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