Physics307L:People/Carrillo/Poisson Distribution

Steve Koch 23:09, 21 December 2010 (EST):Missing a comparison to theoretical Poisson distribution, and you come close, but don't compare the standard deviation to the sqrt of the mean.

Poisson Distribution Lab Summary

• Please note that Ginny was my lab partner.

Purpose/Summary

This simple experiment was intended to help us gain familiarity with the Poisson distribution which is the second most important statistical distribution in physics. In this lab we study the distribution of radioactive decays. The Poisson distribution describes the results of experiments where one counts events that occur at random but at a different average rate. This distribution is of significant importance in all of atomic and subatomic physics.

Analysis

For this lab we collected data measuring the incidences of radioactive events at different dwell times. The dwell times were at 10,20,40,80,100,200,400, and 800 ms. Using the data from each different dwell time, we found the average values for each set and the standard deviations. We then graphed the frequency of the number of counts per channel vs. the number of counts per channel. Ginny used MATLAB and Excel to plot the graphs.

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Conclusion

This image above shows all of our separate dwell times graphed together, showing that the peak of the distribution shifts to the right as dwell time is increased. We noticed that the distribution became wider as we increased the dwell time. In conclusion, I thought this experiment was not as bad as I thought it would be, and I feel like we got some pretty good results seeing that our standard deviation was pretty low.