Status of GNDS support in AMPX/SAMMY and future outlook [Slides]
Abstract not provided.
97 MATHEMATICS AND COMPUTING↗
SEARCH · Engineering Papers
Results for “Criticality Safety”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Bayesian Monte-Carlo Evaluation Framework for Imperfect Data [Slides]
BMC evaluation is a tool to address imperfect data & models, non-linear models, and non-normal PDFs. New posterior PDFs may need new storage formats to allow storage of non-normal PDFs. Storing posterior sets allows for: variance, covariance, skewness, etc.
97 MATHEMATICS AND COMPUTING↗
Updates to the n+ 63,65 Cu Angular Distributions [Slides]
The performance of the benchmark suite is very sensitive to changes in the angular distribution data. The quasi-differential measurements performed by Blain et al at RPI provide a valuable constraint. Furthermore, ENDF/B-VIII.0 disagrees with their measurements consistently at 300 keV (the transition between RRR and high energy). The next step is to conservatively adjust the Legendre coefficients near 300 keV, validating performance against both critical benchmarks and the RPI quasi-differential measurements.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
Evaluated Data for Fissile Actinides in the Resolved and Unresolved Resonance Region and their Coupling to Neutron Multiplicities [Slides]
Abstract not provided.
07 ISOTOPE AND RADIATION SOURCES↗
Validation of KENO Delayed Neutron Fraction (β eff ) Capabilities [Slides]
Not provided.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
Current Status of the Evaluation of ORNL Health Physics Research Reactor Operation Data for CAAS Benchmark Creation [Slides]
This project uses available data from the Health Physics Research Reactor (HPRR) operation to create a benchmark report for inclusion in the ICSBEP, as a Criticality Accident Alarm System (CAAS) shielding benchmark.
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
Oak Ridge National Laboratory NCSP Analytical Methods Subtask 3, AMPX Development and Maintenance, and NCSP Nuclear Data Subtask 6, SAMMY Modernization
The modernization of SAMMY continued with consolidation of access to covariance information for adjusted parameters and data in SAMMY. This consolidation allowed for removal of many scratch files. In addition, work was initiated to make the 0K cross section calculation more modular and less dependent on SAMMY global parameters. An initial application programming interface (API) was added to expose cross sections (including resolution broadening) generated by SAMMY to external fitting routines. The processing for thermal moderators in AMPX was updated for selected moderators for which the generated grid was not fine enough. Updated libraries were generated for SCALE. In addition, work continued to fully support new Evaluated Nuclear Data File (ENDF) formats, including the Generalized Nuclear Database Structure (GNDS) in AMPX.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
GELINA DU-Mo Rotating Target Assembly Fabrication [Slides]
This presentation provides a timeline and delivery schedule for the GELINA DU-Mo Rotating Target, including drawing digitization and translation, fabrication, and assembly.
43 PARTICLE ACCELERATORS↗
NCSP Activities at BNL (FY21) [Slides]
All 3 BNL NCSP (ND, AM, TS) tasks are reported as being on time and slightly under budget. Several COVID-19 related impacts are noted. The release of ENDF/B-VIII.1 has been delayed for 1 year to Feb 2024. New ENDF Library Manager appointment announced as Gustavo Nobre.
96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
Automating neutron resonances classification with Machine Learning [Slides]
Team reported the following accomplishments: the development of a Machine-Learning method to properly assign spins to neutron resonances (automated, general, reproducible); full integration with evaluated resonances in the Atlas (automation of new editions); training and optimization in synthetic data; validation and deployment to real experimental resonances. Future perspectives include exploration of other classifiers and hyper-parameter combinations, further validation with well-known nucleus (e.g. 235 U), and publication pipeline.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
Nuclear Data Activities Supporting MCNP [Slides]
Nuclear Data Team at LANL is working to improve nuclear data availability. These efforts include an updated, modernized, and improved website and a new, dynamic tool for examining what ACE data is on your machine.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
NJOY work in FY21 [Slides]
LANL lists several NJOY priorities for the future, including the maintenance of NJOY2016 for the foreseeable future, as well as the delivery of usable NJOY21 components.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
IER 557: Godiva IV Reproducibility/Characterization [Slides]
The primary goal of the IER 557 Godiva IV reproducibility/characterization process is to determine reproducibility for 70°C bursts. The secondary goal is to characterize the radiation field, including absolute calibration with radchem counting of fission foils.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
IER 488: MUSiC Accomplishments and Goals [Slides]
IER-488: Measurement of Uranium Subcritical and Critical (MUSiC) consists of measurements of bare, HEU systems covering a large range of reactivities. Multiple detector systems and analysis methods are being used to obtain detector-independent results. Massive amounts of data and information available. Substantial analysis has been completed for both critical and subcritical configurations. Work in progress is largely novel research and will result in several conference proceedings, journal publications, and a subcritical benchmark. There is still a large amount of data that has not been analyzed and much more to come from the analysis of the Measurements of Uranium Subcritical and Critical.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
LANL FY21 NCSP Highlights [Slides]
This presentation highlights the activities of Los Alamos National Laboratory (LANL) in fiscal year 2021.These include the celebration of the tenth anniversary of NCERC operations, a large experiment campaign (IER 488 - MUSiC: Measurements of Uranium Subcritical and Critical), preparation for FY22 experiments, the completion of several ongoing experiments, and a control system upgrade project.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
233 U(n,$\gamma$) measurements at LANSCE [Slides]
A new measurement at LANSCE combined DANCE and NEUANCE at the end of 2020 and 2021. The 233 U material was provided by Oak Ridge National Laboratory (December 2020).Two samples of 10 mg and 20 mg of 233 U have been prepared at LANL by Evelyn M. Bond (December 2020). The experiment was performed in December 2020 and June/July 2021. Data analysis is ongoing to extract capture data knowing fission. LANL is looking forward to delivering the capture/fission ratio from (1-300) keV by the end of the FY2022.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Update on 17 O evaluation and fast neutron evaluation for 181 Ta [Slides]
Reliable fast-neutron evaluation can be entirely encapsulated in the reaction model and related input. Ta181 is a particularly relevant case due to extraordinary coverage of various observables by differential experiments that offer much help and relatively little headache. Differences from the similar ENDF/B-VIII evaluation are as follows: more advanced modeling (CC OMP, MSD, MSC, decay schemes), more careful selection of models and parameters, new experimental data, and isomers. Overall, there is improved agreement with differential data and hints of better performance in integral testing.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
Neutron Multiplicity Counting Diagnosis of Uranium Assemblies Interrogated by Cf-252 [Poster]
Researchers concluded: First neutron multiplicity counting of tens of kilograms of 235 U with organic scintillators; leakage multiplication estimates to be improved by incorporating detector cross-talk; provides data comparison for “Multiplicity Theory Beyond the Point Model;" promotes continued use of organic scintillators for NCERC and elsewhere.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗