Download or read book Delayed Neutron Calculations Using ENDF written by and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Data from 20 fission yield sets in ENDF/B-V are used with the emission probabilities (Pn) of 105 delayed neutron precursors to calculate 6-group and total equilibrium delayed neutron yields of (anti .nu./sub d/). Results are compared with recent evaluations and selected measurements of anti .nu./sub d/. Least-squares data adjustment methods are in progress to improve agreement; preliminary results indicate significant improvement when fission yields are adjusted. 2 tables.
Download or read book ENDF B VII 0 Data Testing Using 1 172 Critical Assemblies written by and published by . This book was released on 2007 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to test the ENDF/B-VII.0 neutron data library [1], 1,172 critical assemblies from [2] have been calculated using the Monte Carlo transport code TART [3]. TART's 'best' physics was used for all of these calculations; this included continuous energy cross sections, delayed neutrons in their spectrum that is slower than prompt neutrons, unresolved resonance region self-shielding, the thermal scattering (free atom for all materials plus thermal scattering law data S([alpha], [beta]) when available). In this first pass through the assemblies the objective was to 'quickly' test the validity of the ENDF/B-VII.0 data [1], the assembly models as defined in [2] and coded for use with TART, and TART's physics treatment [3] of these assemblies. With TART we have the option of running criticality problems until K-eff has been calculated to an acceptable input accuracy. In order to 'quickly' calculate all of these assemblies K-eff was calculated in each case to +/- 0.002. For these calculations the assemblies were divided into ten types based on fuel (mixed, Pu239, U233, U235) and median fission energy (Fast, Midi, Slow). A table is provided that shows a summary of these results. This is followed be details for every assembly, and statistical information about the distribution of K-eff for each type of assembly. After a review of these results to eliminate any obvious errors in ENDF/B data, assembly models, or TART physics, all assemblies will be run again to a higher precision. Only after this second run is finished will we have highly precise results. Until then the results presently here should only be interpreted as approximate values of K-eff with a standard deviation of +/- 0.002; for such a large number of assemblies we expected the results to be approximately normal, with a spread out to several times the standard deviation; see the calculated statistical distributions and their comparisons to a normal distribution.
Download or read book Reduced Delayed Neutron Group Representations written by R. E. Skinner and published by . This book was released on 1959 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation and Application of Delayed Neutron Precursor Data written by Michaele Clarice Brady and published by . This book was released on 1988 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accelerator Driven System at Kyoto University Critical Assembly written by Cheol Ho Pyeon and published by Springer. This book was released on 2021-03-20 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book is a unique compilation of experimental benchmark analyses of the accelerator-driven system (ADS) at the Kyoto University Critical Assembly (KUCA) on the most recent advances in the development of computational methods. It is devoted especially to nuclear engineers and scientists. Readers will find a detailed description of advanced measurement techniques and calculation methodologies for the ADS with 14 MeV neutrons and high-energy neutrons (with combined use of 100 MeV protons and Pb-Bi target) at KUCA. Additionally, experimental results of nuclear transmutation of minor actinides by ADS and at a critical state are included. Readers also have access to benchmarks of specific ADS experiments with raw data in the Appendix. The book is a valuable resource for the ADS experiments at KUCA which are globally recognized as both static and kinetic studies from the point of view of fundamental research.
Download or read book An Investigation of the Delayed Neutron Decay Curves Resulting from Uranium and Plutonium Fission written by C. Redman and published by . This book was released on 1944 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effective Delayed Neutron Fraction for the FNR written by Joao Moreira and published by . This book was released on 1983 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energies of the Delayed Neutrons from U235 Fission Products written by and published by . This book was released on 1946 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Determination of the Ranges of the Fission Fragments Emitting Delayed Neutrons Chemical Identification of the 4 51s Delayed Neutron Activity written by N. Sugarman and published by . This book was released on 1946 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Delayed Neutron Reduced Groups by Least Squares written by Thomas E. Springer and published by . This book was released on 1964 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Evaluation of Delayed neutron Data and Associated Covariances written by Daniela Foligno and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the context of nuclear reactor physics, one of the main issues is the control of the chain reaction. After a fission event has occurred, around three prompt neutrons are immediately emitted. Luckily, a small fraction of neutrons - less than 1% - appears with a certain delay with respect to the fission event. Delayed neutrons (DN) are an easy way out from the uncontrollable prompt-neutron driven chain reaction because they slow down the response of the reactor to a change in reactivity. Quantifying the fraction of such neutrons as well as their kinetic behavior is essential to design a safe reactor. The main consequence of a lack of accurate DN data is the conservatism in the design of a reactor. Nowadays, the discrepancy between the reactivity simulated using different international databases, rises up to 16% for LWRs, and the uncertainties associated with the recommended parameters are still too large for the needs of the industry. The DN parameters are generally estimated through a calculation or an integral measurement. This Ph.D. aims at producing a new set of DN parameters by performing both calculations and measurements, and by exploiting the two through the Bayesian inference, with the aim of reducing the uncertainties and creating the associated covariance matrices.The results for 235U, together with the calculated values for 238U, have been tested in three benchmarks, giving satisfying solutions with respect to the effective delayed neutron fraction. The main achievement of this work is the great improvement in the predicted reactivity, especially for negative periods, which is accompanied by an extremely good precision, never exceeding 2.2%.
Download or read book Delayed Neutron Spectra by Decay Group for Fissioning Systems from 227Th Through 255Fm written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The quality and quantity of delayed neutron precursor data has greatly improved over the past approximately 15 years. Supplementation of the data with model calculations and the use of models to extend the number of precursors to 271 is now practical. These data, along with improved fission-product parameters, permit direct calculations of aggregate behavior for many fissioning nuclides. The results can even be approximated using a few (usually six) temporal groups. This paper summarizes an extensive four-year effort to provide a complete set of evaluated data and emphasizes its use to generate the temporal approximations; precursor data and group values are intended for inclusion in ENDF/B-VI. 19 refs., 8 figs., 1 tab.
Download or read book Calculation of Delayed neutron Energy Spectra in a QRPA Hauser Feshbach Model written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Theoretical [beta]-delayed-neutron spectra are calculated based on the Quasiparticle Random-Phase Approximation (QRPA) and the Hauser-Feshbach statistical model. Neutron emissions from an excited daughter nucleus after [beta] decay to the granddaughter residual are more accurately calculated than in previous evaluations, including all the microscopic nuclear structure information, such as a Gamow-Teller strength distribution and discrete states in the granddaughter. The calculated delayed-neutron spectra agree reasonably well with those evaluations in the ENDF decay library, which are based on experimental data. The model was adopted to generate the delayed-neutron spectra for all 271 precursors.
Download or read book Nuclear Data for Science and Technology written by Syed M. Qaim and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1041 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the Proceedings of the International Conference on Nuclear Data for Science and Technology held at Jillich in May 1991. The conference was in a series of application oriented nuclear data conferences organized in the past under the auspices of the Nuclear Energy Agency-Nuclear Data Committee (NEANDC) and with the support of the Nuclear Energy Agency-Committee on Reactor Physics (NEACRP). It was the fIrst international conference on nuclear data held in Germany, with the scientific responsibility entrusted to the Institute of Nuclear Chemistry of the Research Centre Jillich. The scientific programme was established by the International Programme Committee in consultation with the International Advisers, and the NEA and IAEA cooperated in the organization. A total of 328 persons from 37 countries and fIve international organizations participated. The scope of these Proceedings extends to a wide range of interdisciplinary topics dealing with measu rement, calculation, evaluation and application of nuclear data, with a major emphasis on numerical data. Both energy and non-energy related applications are considered and due attention is given to some fundamental aspects relevant to the understanding of nuclear data.
Download or read book Nuclear Cross Sections for Technology written by Joseph L. Fowler and published by . This book was released on 1980 with total page 1062 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ENDF B VI Six group Delayed Neutron Data written by and published by . This book was released on 1989 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper evaluates ENDF/B-VI delayed neutron data for 235U, 238U, and 239Pu. (LSP).
Download or read book An Experiment to Measure Effective Delayed Neutron Fractions written by S. Kaplan and published by . This book was released on 1960 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
