Abstract
The determination of the absorbed dose at a specified location in a medium irradiated with an electron or photon beam normally consists of two steps: (1) the determination of the mean absorbed dose to a detector by using a calibration factor or performing an absolute measurement, (2) the determination of the absorbed dose to the medium at the point of interest by calculations based on the knowledge of the absorbed dose to the detector and the different stopping and scattering properties of the medium and the detector material. When the influence of the detector is so small that the electron fluence in the medium is not modified, the ratio of the mass collision stopping power of the two materials accounts for the differences in energy deposition, and provides a conversion factor to relate the absorbed dose in both materials. Today, all national and international dosimetry protocols and codes of practice are based on such procedures, and the user easily can carry out these steps using tabulated data to convert a measured quantity to absorbed dose in the irradiated medium at the location of interest. Effects due to the spatial extension of the detector are taken into account using perturbation correction factors (see Chapter 25).
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© 1988 Plenum Press, New York
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Andreo, P. (1988). Stopping-Power Ratios for Dosimetry. In: Jenkins, T.M., Nelson, W.R., Rindi, A. (eds) Monte Carlo Transport of Electrons and Photons. Ettore Majorana International Science Series, vol 38. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-1059-4_23
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DOI: https://doi.org/10.1007/978-1-4613-1059-4_23
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