Physics and chemistry of fission. Proceedings of the second IAEA symposium

Fission studies have developed rapidly and significantly since the first IAEA Symposium on the Physics and Chemistry of Fission, held in 1965 in Salzburg. Several surprising discoveries and some excellent experimental results have given rise to many new theoretical investigations. From the individual theoretical models, laboriously improved and carefully fitted to the experimental data, a more general theoretical picture has begun to take shape and this has provided fresh ideas for experimental work. The Second Symposium on the Physics and Chemistry of Fission, held at the IAEA Headquarters in Vienna from 28 July to 1 August 1969, was a short pause in the rapid flow of developing theoretical concepts and new experimental investigations; it was devoted to the discussion, comparison and analysis of the recent achievements, and to a glance at the way fission studies are likely to develop in the near future. Two facts, the emphasis on theory and the important interplay of theory and experiment, left a strong mark on the contributions and discussions. The number of papers dealing with theoretical aspects is substantially larger than at the earlier symposium; this points to the fact that with increased efforts the theoreticians have succeeded in narrowing the wide gap between the large amount of empirical data and the theoretical understanding of it. The titles of individual sessions indicate the new trends in fission research. Theories of fragment distribution, shell structure effects in fissioning nuclei, intermediate structure, and isomeric fission are topics which were discussed with a great deal of uncertainty at the Salzburg symposium. At the present meeting, they were far more prominent and they were argued with great confidence and with the intensity and enthusiasm that only such exciting ideas can arouse. From the extensiveness of the discussion records the vivid interest of the participants is clearly seen; the pertinent problems still to be solved are also revealed. These problems are a challenge for the coming years. A considerable amount of work originally submitted for consideration for inclusion in the Symposium could not be presented orally. The main reasons for this were the obvious time limitations imposed by a week-long symposium, and the need to keep the Proceedings down to a reasonable size. However, abstracts of this work - sometimes in slightly extended form - are included at the end of this book, and readers interested in the work summarized in this section should apply to the individual authors for further details