Technical report Monte Carlo/numerical treatment of alpha -particle spectra from sources buried in bone and resultant doses to surface cells

Abstract

Purpose: To calculate the depth distribution of radioactive decays in bone by fitting a calculated alpha -particle energy spectrum to a measured spectrum. The dose to bone surface cells is then calculated from the depth distribution. Materials and methods: The spectra are calculated using Monte Carlo methods and a numerical depth distribution obtained by trial and error. Results: Alpha spectra for 210Po and 226Ra (plus decay products) in bone were calculated and fitted to experimental spectra. The dose to bone surface cells was calculated using the numerical technique and compared to previously published data. Conclusions: Alpha-particle spectra can be successfully fitted using this method, which gives a more realistic distribution of decays with depth than simple surface and volume models.