ISSN:
1573-8205
Source:
Springer Online Journal Archives 1860-2000
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Physics
Notes:
Abstract Measurements have been made of the energy dependence of the quantity $$\nu _{eff} = \nu \frac{{\sigma _f }}{{\sigma _a }}$$ (wherer is the average number of fast neutrons per fission event, σf is the fission cross section and σa is the absorption cross section) in Pu239 for the energy region ranging from 7 to 30 ev. A knowledge of this quantity is of interest both for practical reactor calculations and in the theory of nuclear fission. The measurements consist of counting the number of fast fission neutrons emitted from a sample of Pu239 with slow neutrons incident upon it. A higher resolving power in the neutron collector has made it possible to measure the ratio $$\frac{{\Gamma _f }}{{\Gamma _y }}$$ for the separate resonances. In this connection it is assumed thatv remains constant over the entire measurement region. From the data of the present work it is found that the fission widths of ten levels in Pu239 vary strongly from one to another and that they may be grouped.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01514611
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