Monte Carlo Determinations Of The Functions A(r, Z) , G(r, theta), g(R) And F(r, theta) For Amersham CDCS-M-TYPE ~(137)Cs SOURCE

摘要

The functions A(r, z), G(r. 6), g(r) and F(r, 8) were calculated for Amersham model CDCS-M-type ~(137)Cs source by means of Monte Carlo simulation using the algorithm PENELOPE. These functions are required to verify and/or to feed planning systems or directly as entrance data for the manual planning of the distribution of absorbed dose according with the recommendations of the TG 43, [1]. The values of the constant A (r, Z) were determined as the quotient of absorbed dose rate distribution in water and airkerma strength in "free air" S_k. The values obtained for A. (r, Z) differ up to 3% of those reported in the literature [2], being very sensitive to the cutoff energy for the electrons in the interface of the source's encapsulated and water.