Gamma correlations

This section of the validation report shows the effect of angular correlations after emission of multiple gammas after a decay. As an example: The background rate of Co-60 depends on both gammas hitting one detector, so the angle between the gammas matter.

Expected correlations

See presentation for more background on the calculation.

The angular correlation functions take an approximate form of

\[W(\theta) = 1 + a_2 \cos^2\theta + a_4 \cos^4\theta\]

For Co-60, the parameters \(a_2 = 1/8\) and \(a_4 = 1/24\) can be obtained from the tables in [1] by normalizing the 0th-coefficient to 1.

Todo

  • expectation for Tl-208

Simulated correlations

Plots of the angle between two emitted gammas after a Co-60 and Tl-208 decay.