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McDonnell, Jordan

Publications and source records attributed to McDonnell, Jordan.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

SCALE/DB-Public

This is a collection of public data produced by AMPX or curated from quality sources that the SCALE code system relies on for user problem input.

Brown, Jesse [Oak Ridge National Laboratory (ORNL)↗
DOE OSTI2024

Photonuclear Physics in SCALE

Radiation shielding modeling involves a wide range of applications, such as power reactors, critical experiments, portable sources, linear accelerators, and fusion systems. Particle energy ranges vary from thermal energies to fast energy spectra. MAVRIC, as the radiation shielding sequence of the SCALE code system [1] developed and maintained by Oak Ridge National Laboratory, is capable of modeling both neutron and photon interactions in matter and is widely used by the US Nuclear Regulatory Commission, Department of Energy, the National Nuclear Security Administration, and radiation shielding practitioners all around the world. Although most applications don’t involve highly energetic photons that can cause photonuclear reactions and create coupled chains of high energy, ionized electrons and bremsstrahlung radiation within a material medium, when present, these reactions can have a significant impact upon the downstream particle fluxes from incident photons above 20 MeV. For example, linear accelerators used for medical isotope production are examples of applications in which high-energetic photons are generated and used for driving or controlling other components of a complex facility. Radiation shielding analyses of such a facility would require accounting for any and all significant sources of radiation. Unfortunately, MAVRIC included no data and methods to model either photonuclear reactions or the bremsstrahlung photons until this work, which enabled accounting for both. Photonuclear reaction cross sections were imported from the Evaluated Nuclear Data File libraries, and corresponding methods were implemented in the SCALE code system; see Section 2 for how the nuclear data are imported and used. Bremsstrahlung photons were modeled by assuming thick-target approximation whereby all generated electrons and positrons due to photon interactions are assumed to be absorbed within the same material in which they were born, yielding a quick particle transport simulation method by using fast lookup tables for generating subsequent gammas; see Section 4 for details. A suite of verification models was used to test implemented methods and associated data. Tests yielded satisfactory results for the new features. Enhancements will be released as part of the next major SCALE release (v7.0), which is anticipated to be deployed in 2025, with beta releases available in the interim.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Resonance Parameter Evaluation of n + 88 Sr reactions for ENDF/B-VIII.1 Library

An evaluation of n+ 88 Sr reactions up to 950 keV was compiled from a publicly available set of resonance parameters. Starting from the repository of the ENDF/B-VIII.0 library, an evaluated nuclear data file was assembled and submitted for inclusion to the Evaluated Nuclear Data File (ENDF)/B-VIII.1 release. This evaluation features an external function representation defined by pole strengths and R ∞ parameters over the entire resolved resonance range. This work improves the modeling of the R-matrix parameterization from multi-Level Breit-Wigner resonance parameters to Reich-Moore formalism, and it also extends thrice the upper energy range of the current ENDF/B-VIII.0 resolved resonance evaluation.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

ENDF/B-VIII.1 and AMPX [Slides]

This presentation is on ENDF/B-VIII.1 and AMPX. This presentation begins with a brief introduction to the AMPX nuclear data processing code. The lecture then touches on nuclear data libraries that ship with the SCALE code system. Finally, this lecture concludes on preparations for the ENDF/B-VIII.1 libraries.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Fission Product Yields: SCALE/ORNL Perspective [Slides]

This presentation covers a few key points. First and foremost, that ORIGEN is a consumer of FPY data. Secondly, TRITON and POLARIS are assets which can be used to validate new FPY data, e.g., from existing radiochemical benchmarks and new irradiation experiments. Lastly, this presentation finds that new capabilities with covariance data should be developed, and V and V methods and analysis are also needed for the covariance data.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

SCALE

SCALE v6.3.1 is a beta version built from existing SCALE code. This code provides modeling and simulation of nuclear reactor physics, criticality safety, radiation shielding, and associated spent fuel characterization for nuclear facilities and nuclear fuel transportation and storage package designs (please see attachment for more details).

Ade, Brian↗
DOE OSTI2022

SAMMY Modernization Efforts [Slides]

This presentation discusses SAMMY releases and states that all of its dependencies are freely available. It also discusses version control and confirms that versions will be tagged as needed. Additionally, SAMMY program flow is discussed and states that the program flow was improved to allow for easier external access to SAMMY routines. Modernization of SAMMY is continued with the Doppler and Resolution broadening modules. The presentation concludes by stating that documentation updates are in progress.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Modernization efforts for the R-Matrix code SAMMY [Slides]

This presentation details modernization efforts for the R-Matrix code SAMMY. It provides an overview of SAMMY, modernization and maintenance goals, modernization accomplishments, covariance data, SAMMY API development, as well as future plans.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Updates and Validation for the n+ 63,65 Cu Cross Sections [Abstract]

The neutron induced total, elastic, and capture cross sections of 63,65 Cu isotopes were selected for evaluation in the resolved and unresolved resonance energy ranges by the National Criticality Safety Program to resolve discrepancies related to benchmark performance. This is especially evident for the series of ZEUS benchmarks in which copper is used as a reflector. Because copper is also used as structural material in both fission and fusion reactors, the need to address benchmark discrepancies linked to nuclear data deficiencies is a task of primary importance. The aim of this work is to describe the steps of evaluation work towards a consistent improvement of the benchmark performance. The R-matrix analysis with the SAMMY code focused on the 63 Cu(n,γ) reaction channel between 100-300 keV coupled to unresolved resonance region parameters up to 650 keV to fit average cross section data from a recent experiment. Due to the high sensitivity of many benchmarks to elastic scattering angular distribution data, especially for the 65 Cu isotope, the impact of these data was tested by generating Legendre coefficients from both resonance parameters and the Hauser-Feshbach model. Guided by the findings of Shaw et al., the performance of the current evaluation for 65 Cu was compared to that of ENDF/B-VII.1 and ENDF/B-VIII.0 by testing the reactivity coefficients corresponding to the validation suite of experimental criticality benchmarks for thermal, intermediate, and fast systems taken from the International Criticality Safety Benchmark Experiments Project Handbook. The benchmark performance is especially sensitive to 63 Cu(n,γ) and 65 Cu elastic scattering for neutron energies in the 100–500 keV region, whereas 100 keV is the upper limit of the resolved resonance region in the ENDF/B-VIII.0 evaluations for 63,65 Cu. The results highlight the need to handle the transition from the resolved resonance region to the high energy region carefully.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2022

Status of GNDS support in AMPX [Slides]

This presentation provides an overview of ENDF reading in AMPX, as well as information regarding low level access classes for GNDS used in AMPX and the use of these classes in AMPX and SAMMY.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

SCALE Sensitivity Tutorial [Slides]

In sensitivity analysis, we seek to quantify the degree to which fundamental data (i.e., nuclear data) influence a system’s response. In uncertainty analysis, we seek to quantify the degree to which uncertainty in fundamental data contributes to uncertainty in a system’s response. In SCALE, the TSUNAMI suite provides tools for sensitivity and uncertainty analysis, similarity analysis, and nuclear data and covariance adjustment.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗