Spectrum

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

To calculate the background of the data, the position between 350 and 500 was selected, this have a plot of which had a bright pixel as shown,

  • Background with bright pixel:
    Background_cadmium_plot.png
by ommiting the bright pixel a histogram of the data could be plotted.

  • Background histogram:
    Background_cadmium_histogram.png
The mean and the standard deviation were calculated using the numpy package and were equal to:

mean = 149775.0,

stdev = 20571.1,

however for a poisson distribution where,

f(n,l) = (l^n)( e^{-l})/(n!)

l is equal to the expextation value and the variance, therefore for the distribution to be poisson the mean should be equal to the square of the standard deviation.

-- JosephBayley - 13 Oct 2015

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Topic revision: r2 - 13 Oct 2015 - JosephBayley

 
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