Experimental and Computer Simulation Study of the Radionuclides Produced in Thin Bi-209 Targets by 130 MeV and 1.5 GeV Protons

The results of experimental and computer simulation studies of the yields of residual product nuclei in Bi-209 thin targets irradiated by 130 MeV and 1.5 GeV protons are presented. The yields were measured by direct high-precision gamma-spectrometry. The gamma-spectrometer resolution was 1.8 keV in the 1332 keV line. The gamma-spectra were processed by the ASPRO code. The gamma-lines were identified, and the cross sections defined, by the SIGMA code using the GDISP radioactive database. The process was monitored by the Al-27(p,x)Na-24 reaction. Results are presented for comparisons between the 209-Bi(p,x) reaction yields obtained experimentally and simulated by the HETC, GNASH, LAHET, INUCL, CEM95, CASCADE, and ALICE codes.Comment: 31 pages, LaTeX, 6 tables, 12 figures available upon request from [email protected] or [email protected] (not available in electronic form), to be published in NIM

104 THE ITEP CONCEPT OF THE ACCELERATOR OF RADIOACTIVE WASTE TRANSMUTATION

Transmutation based on a high current accelerator of protons is considered at ITEP as most effective. A thermal neutron flux in the 10:Sn/cm2sec range is enabled by a 1.5GeV-100mA class proton accelerator. Besides not beeing safe, this flux level is at present difficult to achieve with the help of fission reactor, The high flux of thermal neutrons gives us an opportunity to incinerate all the essential actinides and fission products. The large thermal cross sections offer the advantages of both small actinide loading and high transmutation performance. A liquid mixture of incinerated waste circulates through the blanket and the heat exchanger which makes continuous processing possible, In this way two big demerits of the closed fuel cycle on solid elements can be avoided: a very complicated remote fabrication of fuel elements and secondary radioactive waste from construction materials. Besides, the hybrid system is always subcritical which ensures a high level of nuclear safety. The accelerator driven heavy water assembly allows to build up step by step the potential possibilities of the system and subsequently to solve the following problems: actinide transmutation without electric power production; actinide transmutation with electric power production; a ’33U production or a 23gPu conversion to ‘“U; transmutation of the fission products. 1