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Lab 1: Photon Counting with a PMT
The Statistics of Light
Joey Cheung - jcheung@ugastro.berkeley.edu
Lab Partners: Elizabeth Niespolo, Paul Higgins, Jeff Yen
September 12, 2006

Abstract:

Data acquisition and error analysis are integral parts of any quantitative experiment or survey. In our introductory lab assignment we were required to analyze the statistical properties of a computerized experiment used to count photons from an LED. The end objective was to examine how errors from varying the parameters of the experiment, mainly the number of samples and the count rate, could be analyzed using statistical methods. We found that Poisson statistics provided the best fit to our data. By overlaying the Poisson distribution of the estimated parent population over the sample population, we were able to see the correlation between the samples acquired during the experiment and the theoretical Poisson probability distribution function. The Gaussian also provided a good fit to the data as we increased the number of counts that we were receiving. The Gaussian approximation got increasingly better as the number of counts went up. These approximations provided us with a way to quantify some of the physical limitations of our experiment. We found that our approximations improved by a factor of $\sqrt N$ where N is the number of experiments we ran for each data set.




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Joey Cheung 2006-09-27