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AbstractAbstract
[en] A programme was developed for the calculations of (n,xn) reactions using a statistical model taking into account the conservation of angular momentum and parity. The results obtained for the 87Y, 88Y and 89Y isotopes, from the reaction threshold to 16MeV are presented
[fr]
On a construit un programme de calcul des reactions (n,xn) par un modele statistique tenant compte de la conservation du moment angulaire et de la parite. On presente les resultats obtenus pour les isotopes 87, 88 et 89 de l'yttrium, du seuil de la reaction jusqu'a 16MeVOriginal Title
Reactions (n,xn) de noyaux de masse intermediaire (cas des isotopes d'yttrium)
Primary Subject
Source
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France); p. 150-153; Apr 1976
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Report
Literature Type
Progress Report
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AbstractAbstract
No abstract available
Primary Subject
Source
1976; 1 p; International conference on the interactions of neutrons with nuclei; Lowell, Mass., USA; 6 - 9 Jul 1976; Copies available from Service de Documentation, CEN Saclay, BP No2, 91190 Gif-sur-Yvette (France); Published in abstract form only.
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Report
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Conference
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AbstractAbstract
[en] The cross sections are calculated in the energy range up to about 2MeV above the threshold of (n,2n) reactions, using a statistical model involving spin and parity conservation, and preequilibrium emission
[fr]
Les sections efficaces sont calculees, dans un domaine d'energie s'etendant sur 2MeV environ au-dessus du seuil des reactions (n,2n) par un modele statistique tenant compte de la conservation du spin et de la parite et de l'emission de preequilibreOriginal Title
Calcul de la reaction 93Nb(n,2n) et des reactions 197Au(n,2n), (n,p) et (n,α)
Primary Subject
Source
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France); p. 122-125; Jun 1977; p. 122-125
Record Type
Report
Literature Type
Progress Report
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Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Frehaut, J.; Jary, J.
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1978
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1978
AbstractAbstract
[en] (n,2n)cross sections have been measured between threshold and 15 MeV for the even isotopes of Se, Nd, Sm and for the main isotopes of Gd, W, Tl and Pb. For a given excess energy above the reaction threshold sigma(n,2n), on the average, is an increasing function of the mass number A, and is lower for an odd-N isotope than for the adjacent even isotopes. Strong angular momentum and shell effects are observed for Tl and Pb isotopes and for 209Bi. Calculations using a spin and parity independant statistical model are in agreement with experiment for Nd and Sm isotopes, but are very sensitive to the choice of the level densities
[fr]
Les sections efficaces de reaction (n,2n) ont ete mesurees du seuil a 15 MeV pour les isotopes pairs du Se, Nd, Sm et pour les principaux isotopes du Gd, W, Tl et Pb. Pour une valeur donnee de l'energie d'exces au-dessus du seuil de reaction, sigma(n,2n), en moyenne, augmente avec le nombre de masse A pour chaque serie d'isotopes, et est plus faible pour un isotope ayant un nombre impair de neutrons que pour les isotopes pairs voisins. Des effets de couches et de moment angulaire tres importants sont observes pour les isotopes du Tl, du Pb et pour 209 Bi. Les sections efficaces calculees a l'aide d'un modele statistique independant du spin et de la parite pour les isotopes du Nd et du Sm sont en bon accord avec les resultats experimentaux, mais le calcul est tres sensible au choix des densites de niveauxOriginal Title
Systematique des sections efficaces de reaction (n,2n) pour des series d'isotopes separes
Primary Subject
Source
1978; 6 p; International conference on neutron physics and nuclear data for reactors and other applied purposes; Harwell, UK; 25 - 29 Sep 1978
Record Type
Report
Literature Type
Conference; Numerical Data
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INIS IssueINIS Issue
AbstractAbstract
[en] The method of calculating (n,xn) and (n,xnf) reactions by the statistical model was applied to 231Th, 232Th and 233Th in the neutron energy range 1MeV-20MeV
[fr]
La methode de calcul des reactions (n,xn) et (n,xnf) par modele statistique a ete appliquee a 231Th, 232Th et 233Th dans le domaine d'energie 1MeV-20MeVOriginal Title
Reactions (n,xn) et (n,xnf) sur les isotopes 231Th, 232Th et 233Th
Primary Subject
Source
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France); p. 126-129; Jun 1977; p. 126-129
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Report
Literature Type
Progress Report
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INIS IssueINIS Issue
AbstractAbstract
[en] A method for a statistical model evaluation of fission, (n,2n) and (n,3n) cross sections from 2MeV to 20MeV neutrons on 237U, 238U, 239U and 239Pu is presented. It consists of the determination of fission width parameters by a fit to known fission cross-sections. This method makes use of neutron transmission coefficients from an adapted coupled channel model. The neutron, fission and radiative widths are calculated by the statistical model including Fermi gas model level densities. Results are given for 237U, 238U, 239U and 239Pu nuclei
[fr]
On presente une methode d'evaluation par modele statistique des sections efficaces de fission et de reactions (n,2n) et (n,3n) induites par des neutrons sur noyaux lourds dans la gamme d'energie 2MeV-20MeV. Elle consiste en une parametrisation des largeurs de fission au moyen d'un ajustement sur les sections efficaces de fission connues. Cette methode utilise les penetrabilites neutron fournies par un modele de voies couplees adapte, et les differentes largeurs (neutron, fission, radiative) sont calculees par le modele statistique avec des densites de niveaux du type gaz de Fermi. Des resultats sont donnes ici sur les noyaux 237U, 238U, 239U et 239PuOriginal Title
Evaluation par un modele statistique des sections efficaces (n,xn) et (n,xnf) sur des noyaux lourds
Primary Subject
Source
1975; 13 p; 3. National soviet conference on neutron physics; Kiev, USSR; 09 Jun 1975
Record Type
Report
Literature Type
Conference
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INIS VolumeINIS Volume
INIS IssueINIS Issue
Jary, J.; Lagrange, C.
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1978
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1978
AbstractAbstract
[en] Coherent calculations of a set of neutron cross sections for 240Pu-242Pu in the energy range 10 keV-20 MeV using the optical and statistical models are presented. It can be seen that the present analysis shows good general agreement with the various experimental cross sections
[fr]
Les modeles optique et statistique ont ete utilises pour determiner un ensemble physiquement coherent des sections efficaces neutroniques sur 240Pu et 242Pu entre 10 keV et 20 MeV. Les calculs sont en bon accord avec les donnees experimentales dont on disposeOriginal Title
Evaluation par modeles nucleaires des sections efficaces neutroniques des plutonium 240 et 242 entre 10 keV et 20 MeV
Primary Subject
Source
1978; 5 p; International conference on neutron physics and nuclear data for reactors and other applied purposes; Harwell, UK; 25 - 29 Sep 1978
Record Type
Report
Literature Type
Conference; Numerical Data
Report Number
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Jary, J.; Lagrange, C.; Thomet, P.
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1975
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1975
AbstractAbstract
[en] A method for an optical and statistical model evaluation of a coherent set of neutron cross-sections on 238U from 3keV to 20MeV is presented. It is shown that a satisfying determination of various cross-sections can be obtained from an adequate adjustment of the models on some experimental data
[fr]
Une methode d'utilisation des modeles optique et statistique est presentee dans le but de determiner un ensemble physiquement coherent des sections efficaces neutroniques sur 238U entre 3keV et 20MeV. Il est montre qu'un ajustement adequat sur certaines donnees experimentales permet d'evaluer d'autres sections efficaces de facon satisfaisanteOriginal Title
Evaluation par modeles nucleaires d'un ensemble coherent de sections efficaces n+238U entre 3keV et 20MeV
Primary Subject
Source
1975; 23 p; 3. National soviet conference on neutron physics; Kiev, USSR; 09 Jun 1975
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Report
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Conference
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INIS VolumeINIS Volume
INIS IssueINIS Issue
Delaroche, J.P.; Jary, J.
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1977
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France)1977
AbstractAbstract
[en] A parametrisation of the nucleon-197Au optical potential is given. Predictions of various cross-sections are discussed between 10 keV and 30 MeV
Primary Subject
Source
1977; 3 p; 7. Symposium on interactions of fast neutrons with nuclei; Gaussic, German Democratic Republic; 21 - 25 Nov 1977
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Report
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Conference
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AbstractAbstract
[en] A calculation method previously developed for (n,xn) and (n,xnf) reactions and using the statistical model was improved. An estimation of the fission cross section of 237Pu is presented
[fr]
On a ameliore la methode de calcul des reactions (n,xn) et (n,xnf) par modele statistique mise au point precedemment. On presente une estimation de la section efficace de fission de 237PuOriginal Title
Reactions (n,xn) et (n,xnf) sur noyaux lourds
Primary Subject
Source
CEA Centre d'Etudes de Bruyeres-le-Chatel, 92 - Montrouge (France); p. 154-156; Apr 1976
Record Type
Report
Literature Type
Progress Report
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