Stochastic simulation of track density in nuclear track detectors for 10B measurements in autoradiography

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Beam interactions with materials and atoms, 2011-12, Vol.269 (23), p.2781-2785
• Main Authors: Saint Martin, G., Portu, A., Santa Cruz, G.A., Bernaola, O.A.
• Format: Article
• Language: English
• Subjects: Aqueous solutions; Autoradiography; Autoradiography image; BNCT; Density; Detectors; Mathematical models; Standard material; Stochastic simulation; Stochasticity; Track density
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2011.08.031

A standard material with a known amount of 10B has to be used as a reference for a quantitative evaluation of boron concentration in autoradiography images of tissue samples. However, the yield of detected charged particles is conditioned upon certain parameters, such as the critical angle, which are determined by the physical properties of the sample material as well as the particle type and energy. A stochastic model was developed to simulate the process of particle emission in the sample and the resultant production of tracks in a polycarbonate detector in contact with it. The model was then applied to study the influence of the sample material on the final track density, from a theoretical point of view. Liver tissue, borated aqueous solutions and silicon boron doped wafers were considered as sample materials. Using a borated aqueous solution as a reference material is acceptable for evaluating tissue samples under certain conditions. The value of track density calculated with the model for 50 ppm borated aqueous solution was compared to analytical calculations and to experimental measurements in polycarbonate track detector. Differences between values obtained with the model and experimental measurements could be explained by both experimental limitations and model approximations.