Development of BRACSS code for recalculating Q values by Monte Carlo method

The A1/A2 values of SSR-6 [1] are derived from Q values calculated based on the Q system. However it is known that the current values(SSG-26 [2] ) cannot be reproduced sufficiently because some calculation conditions are not clear. Thus we have developed BRACSS code for recalculating the Q values and clarify unclear conditions of the Q system. BRACSS covers the whole radionuclides listed in ICRP Publ.38 [3] and Publ.107 [4]. (We have used the emission data in ICRP Publ.38 for recalculation.) In addition, BRACSS can calculate the exemption values and D values.BRACSS has been verified in cooperation with an expert working group. Unclear conditions (cut-off energy, selection of radiation type, consideration of progenies, etc.) are examined to set suitable parameters through discussion of the group. As a result of recalculating for 387 nuclides listed in SSG-26, it is shown that BRACSS can reproduce the same or close values to the current ones for most nuclides. It proves that BRACSS can better simulate the Q system with our conditions.