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 between 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 factors, the measurements were performed for different photon beam field diameters at the phantom front face, at a fixed source-to-phantom distance of 1 m. An ionization chamber of volume 1 cm3 was used for dose measurement. Measured results are analysed and discussed in comparison with measured and calculated values given in the cited references.