-- AnishaVadher - 14 Oct 2016

- Working out how much background for each pixel
- Plotted a histogram of number of photoelectrons against the frequency for a 0.1s exposure in the dark frame which follows a Gaussian distribution
- Number of photoelectrons = pixel value (ADU) * Gain
- Gain = 2.3 e/ADU (value from PH2900 report)
- From the histogram I will obtain the value at the peak and the error from the FWHM
- Error in the peak = FWHM/2.35
- I will get these statistics for each exposure time in the dark frames that I have taken and plot the peak value as a function of exposure time and the error as a function of exposure time.
- There are big gaps between the bins which I am not sure why.
- Edit - the gaps are due to the fact that the histogram only takes integer values so increasing the number of bins leads to more gaps in the histogram.
- Histrogram of number of photoelectrons for a 0.1s exposure in the dark frame with 45 bins.:

- Also plotted a histogram for the sum of pixel along the x-axis values against frequency for a 0.1s exposure in the dark frame which follows a Poisson distribution
- The histograms from the sum of pixels along the y-axis follows a Gaussian distribution.

- Plotted the median intensity of the pixels as a function of exposure time using the values given from the image using np.median in python. I am yet to work out the errors.

- The median intensity as a function of exposure time.:

- Table of values obtained from Gaussian fit to dark frames

Exposure | Fitted Mean | Fitted Standard Deviation |

0.10 | 917.12 | 6.41 |

0.20 | 916.76 | 6.42 |

0.50 | 916.65 | 6.42 |

001 | 917.73 | 6.43 |

002 | 916.64 | 6.44 |

005 | 917.73 | 6.47 |

010 | 919.34 | 6.48 |

020 | 920.08 | 6.51 |

030 | 920.96 | 6.55 |

040 | 922.16 | 6.58 |

050 | 922.69 | 6.60 |

060 | 922.48 | 6.62 |

090 | 925.88 | 6.71 |

200 | 933.75 | 6.99 |

300 | 939.33 | 7.22 |

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Topic revision: r2 - 27 Oct 2016 - AnishaVadher

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