We measure 114 nuclide-production cross sections for an isotopically enriched 208 Pb target bombarded with 1.0 GeV protons. The cross sections are determined using direct ␥ spectrometry with a high-resolution Ge detector. The cross sections are compared to another experiment which used ␥ spectrometry with a natural Pb target; our results average 7.5% less for nuclides measured in common. They are also compared to a kinematically inverse reaction of 1 GeV/nucleon 208 Pb interacting with a hydrogen target; we find our results average 15% higher than those for ͑a different set of͒ common nuclides. We find there is a systematic discrepancy between the cross sections found from the two very different experimental techniques. We also compare our measurements to eight different models. We find most are fairly reliable in predicting cross sections for nuclides not too far away in mass from Pb, but differ greatly in their reliability for nuclides in the deepspallation and fission mass regions. In the spallation region (Aտ155), the CEM2K code, which includes an intranuclear cascade, followed by a preequilibrium stage, leading finally to equilibrium decay, gives the best representation of our data. In the center of the fission/fragmentation mass region, the INUCL code is the most accurate. INUCL includes the same basic ingredients of cascade, preequilibrium, and evaporation, but differs considerably in details. It also contains a comprehensive fission model, which is lacking in CEM2K. No simulation code tested is reliable for the entire mass range of nuclides measured.

The work is aimed at experimental determining and computer simulating the independent and cumulative yields of residual product nuclei in the target and structure materials of the transmutation facilities driven by high-current accelerators. The ITEP U-10 accelerator was used in 48 experiments to obtain more than 4000 values of the yields of radioactive residual product nuclei in 0.1-2.

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The work is aimed at experimental determination of the independent and cumulative yields of radioactive residual nuclei produced in intermediate-energy proton-irradiated thin targets made of highly isotopic enriched and natural lead ( 206,207,208,nat Pb) and 209 Bi. 5972 radioactive product nuclide yields have been measured in 55 thin targets induced by 0.04, 0.07, 0.10, 0.15, 0.25, 0.6, 0.8, 1.2, 1.4, 1.6, and 2.6 GeV protons extracted from the ITEP U-10 proton synchrotron. The measured data have been compared with data obtained at other laboratories as well as with theoretical simulations by seven codes. We found that the predictive power of the tested codes is different but is satisfactory for most of the nuclides in the spallation region, though none of the codes agree well with the data in the whole mass region of product nuclides and all should be improved further.

A qualitative and quantitative comparison of the recent OSI measurements of the nuclide yields from 208Pb and 238U at 1 OeV/nucleon and 197 Au at 800 MeV/nucleon interactions with protons with the codes LARET (with both IS-ABEL and Bertini options), CEM95, CEM97, CEM2k, CASCADE, CASCADElINPE, YIELDX, RETC, and INUCL is presented The predictive power of these codes is reasonable for nuclides in the near spallation region but is worse for deep spallation and much worse in the fission region. None of these codes agree well with the data in the whole mass region of product nuclides and all must be improved to become reliable tools for accelerator-dri ven applications.