Water phantom backscatter factors for x-rays in the 60 kV to 300 kV region

Experimentally determined values of x-ray backscatter factors are presented in this paper. Measurements were made for x-rays generated at voltages bet ween 60 kV and 300 kV and three water phantoms different in shape and size. To study the influence of the irradiation geometry on the backscatter fact ors, the measurements were performed for different photon beam held diamete rs at the phantom front face, at a fixed source-to-phantom distance of 1 m. An ionization chamber of volume 1 cm(3) was used for dose measurement. Mea sured results are analysed and discussed in comparison with measured and ca lculated values given in the cited references.