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In this article we present the development of a new photonuclear activation library for the CINDER’90 evolution code (LANL). The IAEA evaluations for 164 isotopes are explicitly included and more than 600 isotopes are added using the HMS‐ALICE predictions. GNASH evaluations are used in the case of actinides.

A survey is given about efforts undertaken during the HINDAS project to investigate the energy dependence of residual nuclide production by proton‐induced reactions from thresholds up to 2.6 GeV. For proton‐induced reactions, our experiments aimed to further develop and complete the cross‐section database that was established by our collaboration in recent years. It was extended to the heavy‐target elements Ta, W, Pb, and Bi for energies up to 2.6 GeV. In addition, new measurements for the target element iron were performed up to 2.6 GeV and for natural uranium for energies from 21 MeV to 69 MeV. For the target element lead, a comprehensive set of excitation functions published recently was completed by AMS‐measurements of cross sections for the production of the long‐lived radionuclides Be‐10, Al‐26, Cl‐36, and I‐129 and by mass spectrometric measurements for stable and radioactive rare gas isotopes of He, Ne, Ar, Kr, and Xe. Comprehensive tests of the nuclear‐reaction codes TALYS and INCL4+ABLA, which were developed within the HINDAS project, were performed with the new experimental results over the entire energy range.

The next generation spallation neutron sources, neutrino factories or RIB production facilities currently being designed and constructed world wide will increase the average proton beam power on target by a few orders of magnitude. Increased proton beam power results in target thermal hydraulic issues leading to new target designs, very often based on liquid metal technologies such as Hg, Pb, or PbBi. Radioactive nuclides produced in liquid metal targets are transported into hot cells, into pumps or close to electronics with radiation sensitive components. Besides the considerable amount of photon activity in the irradiated liquid metal, a significant amount of the Delayed Neutron (DN) precursor activity can be accumulated in the target fluid. The transit time from the front of a liquid metal target into areas, where DNs may be important, can be as short as a few seconds, i.e. well within one half‐life of many DN precursors. Therefore, it seems very important to evaluate the DN flux as a function of position and determine if DNs may contribute significantly to the activation and dose rates. The multi‐particle transport code MCNPX combined with the material evolution program CINDER’90 is used to predict the DN precursors and construct the DN tables. These DN tables are employed within the generalized geometrical model of the MegaPie spallation target at PSI (Switzerland). We show that the contribution of DNs and prompt spallation neutrons to the total neutron flux is comparable at the very top of the liquid PbBi loop. We also demonstrate that these estimates of DNs within MCNPX are very much model‐dependent. No experimental data are available for DN yields and time spectra from high energy fission‐spallation reactions. An experiment to perform these measurements is proposed.

This article presents calculations of photonuclear reaction cross sections for actinides by using different reaction codes, namely an improved version of HMS‐ALICE and GNASH. The GDR parameters from the RIPL2 data library are used to describe the total photo‐absorption cross section. In general, our results show satisfactory agreement with experimental data and IAEA evaluations. We plan to include our GNASH evaluations for 235U, 238U, 237Np, 239Pu, 240Pu and 241Am into a new release of the ENDF‐B/VII data files.