IAEA Coordinated Research Program Research Articles

LEU-HTR critical experiment program for the proteus facility in Switzerland

New critical experiments in the framework of an IAEA Coordinated Research Program on “Validation of Safety Related Reactor Physics Calculations for Low-Enriched HTR's” are planned at the PSI PROTEUS facility. The experiments are designed to supplement the experimental data base and reduce the design and licensing uncertainties for small- and medium-sized helium-cooled reactors using low-enriched uranium (LEU) and graphite high temperature fuel. The main objectives of the new experiments are to provide first-of-a-kind high quality experimental data on: 1. (1) the criticality of sample, easy to interpret, single core region LEU HTR systems for several moderator-to-fuel ratios and several lattice geometries; 2. (2) the changes in reactivity, neutron balance components and control rod effectiveness caused by water ingress into this type of reactor; and 3. (3) the effects of the boron and/or hafnium absorbers that are used to modify the reactivity and the power distributions in typical HTR systems. Work on the design and licensing of the modified PROTEUS critical facility is now in progress with the HTR experiments scheduled to begin early in 1991. Several international partners will be involved in the planning, execution, and analysis of these experiments in order to ensure that they are relevant and cost effective with respect to the various gas-cooled reactor national programs.

Recent progress in production and evaluation of atomic data for fusion: Review of a Co-ordinated Research Programme of the IAEA

Work produced in the framework of the IAEA (1980-1984) Co-ordinated Research Programme (CRP) on Atomic Collision Data for Diagnostics of Magnetic Fusion Plasmas is reviewed. The conclusions of this programme and the recommended continuation of the overall work on Atomic and Molecular (A + M) data discussed during three meetings sponsored by the IAEA are presented in detail. For the purpose of completeness, the present review also provides information on data produced and/or evaluated outside this CRP, as well as data relevant to fusion plasma modelling. The highlights of data production and evaluation activity after termination of the CRP are also covered.

Nuclear decay data: Some applications and needs

Abstract Nuclear decay data have broad relevance to a number of basic scientific disciplines as well as to many areas of technology. In this paper we discuss selected applications where decay data are making, or promise to make, important contributions. The following specific illustrations are discussed: the 1arge body of precise new actinide-nuclide decay data produced through the work of the recently concluded IAEA Coordinated Research Program on the Measurement and Evaluation of Transactinium Isotope Nuclear Decay Data; the use of actinide-nuclide half-lives as reference standards in nuclear-data measurements; and the relevance of short-lived fission-product decay data to basic physics and reactor technology and some of the problems and challenges that they present to both theory and experiment.

The IAEA coordinated research programme on the measurement and evaluation of transactinium-isotope nuclear decay data

In 1977 the Nuclear Data Section of the Atomic Energy Agency organized a Coordinated Research Programme on the Measurement and Evaluation of Transactinium-Isotope Nuclear Decay Data. The objectives of the Coordinated Research Programme, its organization, the achievements and the ongoing work are reported.