Published May 1967 | Version v1
Book

Prompt fission neutrons -measurement of ν-bar and of the probabilities P(ν) of emission of v-neutrons

  • 1. CEA, Centre d'Etudes Nucleaires de Bruyeres Le Chatel (France)

Description

With a large liquid scintillator in conjunction with a fission-fragment detector, we hope to measure the values of ν-bar and P(v) for different fissile materials to better than 1% in fissions produced by neutrons in the energy range 4-14 MeV. To estimate the various sources of error in these measurements, we have carried out preliminary work on the spontaneous fissions of 252Cf and 240Pu: measurement of the efficiency of the liquid scintillator; variation of ν-bar with the kinetic energy of the fragment detected; variation of the efficiency of the liquid scintillator with the geometry of the fission-fragment detector; correction of the experimental results and experimental check of these corrections. We measured the P(ν) of 252Cf and the ν-bar and P(ν) of 240Pu in spontaneous fission. In absolute values, it is the inexact knowledge of the reference ν-bar (252Cf) which limits the accuracy of these measurements. (author)

Abstract (French)

En utilisant la technique du gros scintillateur liquide associe a un detecteur de fragments de fission, les auteurs envisagent de mesurer a mieux que 1% ν-bar et P(v) pour differents materiaux fissiles, dans les fissions provoquees par des neutrons dans le domaine d'energie compris entre 4 et 14 MeV. A cette fin, pour apprecier l'importance des differentes sources d'erreurs intervenant dans ces mesures, ils ont effectue differents travaux preliminaires pour les fissions spontanees de 252Cf et de 240Pu: mesure de l'efficacite du scintillateur liquide; variation de ν-bar avec l'energie cinetique du fragment detecte; variation de l'efficacite du scintillateur liquide avec la geometrie du detecteur de fragments de fission; corrections des resultats experimentaux, controle experimental de ces corrections. Les resultats presentes concernent la distribution des P(v) pour la fission spontanee de 252Cf et les valeurs de ν-bar et de P(v) pour la fission spontanee de 240Pu. En mesure absolue, c'est l'imprecision avec laquelle on connait la valeur du ν-bar de reference (252Cf) qui limite la precision des mesures. (author)
Part of:
Nuclear data for reactors. Proceedings of a conference on nuclear data - microscopic cross-sections and other data basic for reactors. V. 2

Additional details

Additional titles

Original title (French)
Neutrons prompts de fission-mesure de ν-bar et des probabilites P(v) d'emission de v neutrons

Publishing Information

Publisher
IAEA
Imprint Place
Vienna (Austria)
Imprint Title
Nuclear data for reactors. Proceedings of a conference on nuclear data - microscopic cross-sections and other data basic for reactors. V. 2
Imprint Pagination
454 p.
Series
Proceedings series
Journal Page Range
p. 57-66
ISSN
0074-1884

Conference

Title
Conference on nuclear data - microscopic cross-sections and other data basic for reactors
Dates
17-21 Oct 1966
Place
Paris (France)

Optional Information

Notes
8 refs, 7 figs, 2 tabs Imprint:Published in two volumes
Secondary number(s)
IAEA-CN--23/77