Determination of central axis depth dose for a co-57 external radiation source

An optimum excitation of a kidney phantom was assessed using 80 and 130 half-angle divergent collimators. The study was performed using Co-57 as the source of radiation. It also reported a method to calculate central axis depth dose. Signal to square root of background radiation ratio, (directly related to detection limit) for the 80 and 130 collimators were found to be 34.0 and 38.0 respectively. The central axis depth dose was measured at 5 cm from the posterior depth. Results for the 80 and 130 collimators measurement were found to be 0.23 and 0.25 mGy respectively. It was concluded that the 130 collimator performed better than the other