Abstract
Recently, the radioactive source Jr-192 has been replacing Co-60 as a high dose rate (HDR)remote afterloading system (RALS) brachytherapy source. Two-dimensional relative dose distributions have been measured around HDR Jr-192 source in a water phantom within a plane through the source axis. Measurement has been made for distances between 1 and 10 cm and for angles 0to 90 degree from the source center. Data have been corrected for background and finite detector volume. Two physical parameters, radial dose function and anisotropy function, have been calculated from measured data. The results indicate that the anisotropy increases as the angle decreases. This effect resulted from increasing of attenuation of the source encapsulation wall at small angles.
