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Showing 1 to 18 of 18 for “"spontaneous fission"”.
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Neutron spectrum from 252Cf spontaneous fission
… have been made of the neutron spectrum from the spontaneous fission of 252Cf in the restframe of the fragment by simultaneous observation of the neutron time-of-flight and the fragment velocity. The fragments were detected by means of thin film plastic scintillators in which the scintillation …
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Neutron-neutron angular correlation in 252Cf spontaneous fission
… between prompt neutrons emitted in 252 cf spontaneous fission has been measured. The observed correlation is compared with a theoretical calculation based on the evaporation model of neutron emission. It is found that the evaporation model is unable to account for the observed strong …
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A NEW MEASUREMENT OF THE NEUTRON MULTIPLICITY EMITTED IN 252Cf SPONTANEOUS FISSION
… probability distribution emitted during spontaneous fissions, with an average multiplicity of 3.81 ± 0.05 neutrons per fission.
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Measured X-Ray Multiplicities and Element Yields in the Spontaneous Fission of Californium-252
Made available in DSpace on 2014-12-14T06:26:03Z (GMT). No. of bitstreams: 1 7709076.pdf: 3525742 bytes, checksum: c48c1fdaa5923d248218accc9c8b04d9 (MD5) Previous issue date: 1976
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Direct and absolute measurements of average yield of neutrons in thermal fission of U²³⁵ and spontaneous fission of Cf²⁵²
… and prompt-neutron coincidence calibration of fission counters, have been carried out to obtain independent evaluations the total yield of neutrons in thermal fission of U²³⁵[ν̅(U²³⁵)] and spontaneous fission of Cf²⁵²[ν̅(Cf²⁵²)]. In this experiment, the neutron-fission coincidence phase was …
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Noble gases anomalies in terrestrial ores and meteorites
… by the use of high neutron flux. The relative fission yields from the spontaneous fission of ²⁵²Cf for krypton and xenon isotopes are ⁸³Kr :⁸⁴Kr :⁸⁵Kr :⁸⁶Kr::¹³¹Xe:¹³²Xe:¹³⁴Xe:¹³⁶Xe = 0.010:0.017:0 0049:0.032:0.35:0.52:0.92:≡1.000. A comparison of these results with the spontaneous fission …
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Characteristics of light charged particle emission in spontaneous and neutron induced fission of Cm and Cf isotopes
Talking about fission, people think almost automatically about a nucleus that splits into two heavy pieces. However, in 1946 the phenomenon of ternary fission has been discovered, in which the two fission fragments are accompanied by a light charged particle. Ternary fission data are of interest …
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Prompt neutrons from fission of 252Cf and 235U
… n-n angular correlation for neutrons emitted in spontaneous fission of ²⁵²Cf and thermal-neutron- induced fission of ²³⁵U. The dependence of the angular correlation on the neutron detection threshold energy was investigated. These measurements and other experimental data on the fission spectrum …
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Examination of natural background sources of radioactive noble gases with CTBT significance
… must be calculated. This work examines the fission products produced by spontaneous fission of ²³⁸U, which is naturally present in the earth's crust, and of ²⁴⁰Pu which is present as a product of nuclear weapons and nuclear reactor accidents. These calculations provide a range of production …
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Construction and Testing of a Portable Time Projection Chamber for Fast Neutron Detection
… fuel, the fast neutron signature from the spontaneous fission of Plutonium-240 offers a window of opportunity for interdicting illicit nuclear material movement. Directly detecting fast neutrons, as opposed to reaction-based detectors that rely on signal moderation, retains the directional …
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Energy correlations of prompt neutrons from 252Cf fission
… for coincident neutrons emitted in the spontaneous fission of ²⁵²Cf. The hypothesis that cooling of the fission fragments during the cascade evaporation of prompt neutrons affects the energies of successive neutrons in a cascade has been investigated by a comparison of the energy …
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The Effect of Pressure on Ion Track Formation in Minerals
… nm. In nature, such trails are generated by spontaneous fission of 238U-nuclei. So far, irradiation experiments with heavy ions were always performed under vacuum conditions. Studies of ion-track formation in pressurized solids are expected to contribute to an improved understanding of the …
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Advanced brachytherapy dosimetric considerations
… and 252Cf. 252Cf sources also emit neutrons from spontaneous fission. The brachytherapy dosimetry protocol recommended by the American Association of Physicists in Medicine was followed and evaluated for conditions of partial scatter (non-infinite media) and material inhomogeneities, both commonly …
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Noble gases: a record of the early solar system
… ¹³⁰Te. 4. The xenon and krypton yields from the spontaneous fission of ²⁵²Cf"--Abstract, pages ii-iii.
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Gamma and neutron dose profiles near a Cf-252 brachytherapy source
… prompt gamma spectrum as well as the true Cf-252 spontaneous fission yield data to explicitly model delayed gamma emissions from fission products. We also investigated the bremsstrahlung x-rays produced by the beta particles emitted from fission-product decays. The results show that the …
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Development of a Novel Fuel Burnup Methodology and Algorithm in RAPID and its Benchmarking and Automation
… RAPID code system for accurate calculation of 3D fission source distributions as the trans- port calculation tool to drive the 3D burnup calculation. bRAPID is capable of accurately and efficiently calculating assembly-wise axially-dependent fission source and burnup dis- tributions, and …
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NUCLEAR DEFORMATION IN FISSION FRAGMENTS STUDIED WITH NOVEL IMPLEMENTATIONS OF DOPPLER SHIFT LIFETIME MEASUREMENT TECHNIQUES
… measurement of lifetimes of excited states in fission fragments. This method has been applied to the first set of data taken with an active fis- sion target coupled to an array of germanium detectors. The nuclei have been populated via neutron-induced fission on 235 U, dissolved in a liquid …
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Quantification and propagation of nuclear data uncertainties
… is investigated in the context of the prompt fission neutron spectrum (PFNS) uncertainties and its impact on critical reactor assemblies. First, the first-order, linear Kalman filter is used as a nuclear data evaluation and uncertainty quantification tool combining available PFNS experimental …