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Total and Partial Photoneutron Reactions Cross Sections – New Analysis and Evaluationтезисы доклада
Информация о цитировании статьи получена из
Web of Science
Дата последнего поиска статьи во внешних источниках: 29 мая 2015 г.
- Авторы: Ishkhanov B.S., Orlin V.N., Varlamov V.V.
- Сборник: The International Conference “Nuclear Structure and Related Topics". July 3 – 7, 2012, Dubna, Russia. Book of Abstracts
- Тезисы
- Год издания: 2012
- Место издания: Joint Institute of Nuclear Researech Dubna
- Первая страница: 45
- Последняя страница: 45
- Аннотация: Accurate and reliable data of total and partial photoneutron reaction cross sections are required in both basic and applied research and many applications. Those are primarily investigations of structure and dynamic of atomic nucleus, nuclear reaction mechanisms, etc. Such kind data were obtained for many nuclei in various experiments using bremsstrahlung (majority has been carried out at Moscow and Saratov State Universities (Russia), University of Melbourne (Australia) and some other laboratories [1]) and quasimonoenergetic annihilation photons (majority - at Livermore (USA), Saclay (France) and some other laboratories. Unfortunately there are significant systematic disagreements between the results of various experiments for partial photoneutron reactions (g,n), (g,2n) and (g,3n) cross sections. That makes actual the tasks of investigation of cross sections reliability and authenticity, and of development of methods for those disagreements overcoming. For solving the first task the objective absolute criteria were proposed – transitional photoneutron multiplicity functions Fi = SIG(g,in)/SIG(g,xn) = SIG(g,in)/[SIG(g,n) + 2SIG(g,2n) + 3SIG(g,3n) + …], F1 , F2, F3,… have values not higher than 1.00, 0.50, 0.33,…., correspondingly. Additionally functions fi = SIG(g,in)/SIG(g,sn) = SIG(g,in)/[SIG-exp(g,n) + SIG-exp(g,2n) + SIG-exp(g,3n) + …] were used (fi < 1.0). Systematical analysis of data using Fi revealed that many published data are not reliable and authentic (F2 > 0.5). For solving the second research task the new experimentally-theoretical treatment was proposed in which only experimental data for total neutron yield reaction cross section эксп(,xn), free from the neutron multiplicity sorting problems, is used for partial reaction cross section evaluation together with functions Fitheor, calculated in the frame of modern model for photonuclear reactions [3, 4]. Evaluations of reliable and authentic data on cross sections for partial reactions (g,n), (g,2n) and (g,3n) - SIg-eval(g,in) = Fi-theor x SIG-exp(g,xn) - were carried out for 90Zr, 115In, 112,114,116,117,118,119,120,122,124Sn, 159Tb and 197Au in agreement with the results of modern induced activity experiments free from neutron multiplicity sorting problems. In many cases deviations of evaluated data from experimental ones are enough high, so the situation found out creates a lot of serious physical problems waiting of new treatment – many very important things for various applications must be reanalyzed.
- Добавил в систему: Варламов Владимир Васильевич