A Microdosimetric Algorithm for Electron Point Kernel Data: 2. Beta Sources

Using the results from earlier work, a microdosimetric algorithm has been developed to provide beta dose point kernel data in the form of probability density functions of specific energy. This algorithm includes parametric representations of the probabilistic point kernel data for monoenergetic electron sources. The algorithm has been applied to beta emitters 131I and 90Y. A 1µm diameter sphere was used to model microscopic size targets in the earlier work and also in this study. Good agreement is observed between mean specific energies z, from the probabilistic beta dose point kernel data and absorbed dose values, D, from conventional point kernel data. By applying this algorithm, one can produce probabilistic dose point kernel data for beta emitters that have endpoint energies below 2.5 MeV.