Measurement of radioactive fragment production excitation functions of lead by 400 MeV/u carbon ions

Ogawa, Tatsuhiko   ; Morev, M. N.*; Kosako, Toshiso*

Depth distributions of radioactive fragments in a thick lead target exposed to 400 MeV/u carbon ions were measured to obtain isotopic production cross-sections of Pb(C,x)X (X=Sc, V, Mn, Co, Co, Fe, Se, Rb, Sr, Sn, Te, Xe, Ba, Ce, Pm, Pm, Gd, Eu, Gd, Hf and Hf) reactions as excitation functions. The obtained fragment distributions were converted to excitation functions of fragmentation cross-sections by the modified stacked-foil method. This conversion procedure was validated by comparing the obtained data with the available thin target experimental data. The obtained cross-sections were in good agreement with the previously published results. Comparison of the obtained cross-sections and the simulation by PHITS showed that PHITS underestimates fragments lighter than 90 amu by factor of about 10 whereas the fragments heavier than 110 amu were predicted within a factor of 3. Energy and mass dependences of the obtained cross-sections give insight into the reaction mechanism and will be useful for radiation transport code benchmarking. Furthermore, this study clarified that excitation functions of fragmentation reactions induced by heavy ions can be obtained by applying the method adopted in this study.