# Parameter optimization and uncertainty analysis of $FREYA$ for spontaneous fission

## Abstract

In this work we propose an effort to determine an optimal parameter set for the complete event fission model to reproduce spontaneous fission of ^{252}Cf(sf), ^{244}Cm(sf), ^{238}Pu(sf), ^{240}Pu(sf), ^{242}Pu(sf), and ^{238}U(sf). Earlier studies have partially optimized the event-by-event fission model with respect to the available experimental data using brute force computational techniques. We have confirmed and expanded these results using a least-squares minimization based on the simulated annealing approach. We have furthermore developed a more complete statistical picture of this optimization, consisting of a full correlation matrix for the parameters utilized by . The newly improved parameter values themselves, along with this correlation matrix, have led to a more well-developed physical picture of the fission process.

- Authors:

- Publication Date:

- Research Org.:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of California, Berkeley, CA (United States)

- Sponsoring Org.:
- USDOE; USDOE NA Office of Nonproliferation and Verification Research and Development (NA-22)

- OSTI Identifier:
- 1513149

- Alternate Identifier(s):
- OSTI ID: 1513240; OSTI ID: 1547898

- Report Number(s):
- LLNL-JRNL-757823

Journal ID: ISSN 0168-9002; 945771

- Grant/Contract Number:
- AC52-07NA27344; NA0003180; AC02-05CH11231

- Resource Type:
- Accepted Manuscript

- Journal Name:
- Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment

- Additional Journal Information:
- Journal Volume: 922; Journal Issue: C; Journal ID: ISSN 0168-9002

- Publisher:
- Elsevier

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; Nuclear Fission; Modeling; FREYA

### Citation Formats

```
Van Dyke, J., Bernstein, L. A., and Vogt, R.. Parameter optimization and uncertainty analysis of FREYA for spontaneous fission. United States: N. p., 2019.
Web. https://doi.org/10.1016/j.nima.2019.01.001.
```

```
Van Dyke, J., Bernstein, L. A., & Vogt, R.. Parameter optimization and uncertainty analysis of FREYA for spontaneous fission. United States. https://doi.org/10.1016/j.nima.2019.01.001
```

```
Van Dyke, J., Bernstein, L. A., and Vogt, R.. Mon .
"Parameter optimization and uncertainty analysis of FREYA for spontaneous fission". United States. https://doi.org/10.1016/j.nima.2019.01.001. https://www.osti.gov/servlets/purl/1513149.
```

```
@article{osti_1513149,
```

title = {Parameter optimization and uncertainty analysis of FREYA for spontaneous fission},

author = {Van Dyke, J. and Bernstein, L. A. and Vogt, R.},

abstractNote = {In this work we propose an effort to determine an optimal parameter set for the complete event fission model to reproduce spontaneous fission of 252Cf(sf), 244Cm(sf), 238Pu(sf), 240Pu(sf), 242Pu(sf), and 238U(sf). Earlier studies have partially optimized the event-by-event fission model with respect to the available experimental data using brute force computational techniques. We have confirmed and expanded these results using a least-squares minimization based on the simulated annealing approach. We have furthermore developed a more complete statistical picture of this optimization, consisting of a full correlation matrix for the parameters utilized by . The newly improved parameter values themselves, along with this correlation matrix, have led to a more well-developed physical picture of the fission process.},

doi = {10.1016/j.nima.2019.01.001},

journal = {Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment},

number = C,

volume = 922,

place = {United States},

year = {2019},

month = {4}

}

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Works referencing / citing this record:

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