Measurements of the Prompt Fission Neutron Spectrum at LANSCE: The Chi-Nu Experiment

Kelly, Keegan John; Devlin, Matthew James; Gomez, Jaime A.; O'Donnell, John M.; Taddeucci, Terry Nicholas; Haight, Robert Cameron; Lee, Hye Young; Mosby, Shea Morgan; Fotiadis, Nikolaos; Neudecker, Denise; Talou, Patrick; Rising, Michael Evan; White, Morgan Curtis; Solomon, Clell Jeffrey Jr.; Wu, Ching-Yen; Bucher, Brian Michael; Buckner, Matthew Quinn; Henderson, Roger Alan

doi:10.1051/epjconf/201819303003

Title: Measurements of the Prompt Fission Neutron Spectrum at LANSCE: The Chi-Nu Experiment

Abstract

The goal of the Chi-Nu experiment at the Los Alamos Neutron Science Center is to measure the prompt fission neutron spectra from major actinides using a double time-of-flight method with a pulsed, white incoming neutron source. Fission events are detected with a parallel-plate avalanche counter and outgoing neutrons are detected with either a ⁶Li-glass or liquid scintillator detector array for low- or high-energy neutrons, respectively. A detector response matrix for the interaction of neutrons with the experimental environment for neutrons measured with the Chi-Nu ⁶Li-glass detector array has been calculated to obtain a full understanding of the measured Chi-Nu data and also to allow for nearly instantaneous production of simulated Chi-Nu data spectra. Prompt fission neutron spectra corresponding to 19 incoming neutron energy ranges from 0.7-20 MeV have been extracted using the ratio-of-ratios method with Chi-Nu ⁶Li-glass data on the neutron-induced fission of ²³⁵U.

Authors:

^[1];

^[1]; O'Donnell, John M. ^[1]; Taddeucci, Terry Nicholas ^[1]; Haight, Robert Cameron ^[1];

^[1];

^[1]; Solomon, Clell Jeffrey Jr. ^[1]; Wu, Ching-Yen ^[2]; Bucher, Brian Michael ^[2]; Buckner, Matthew Quinn ^[2]; Henderson, Roger Alan ^[2]

Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: Wed Nov 14 00:00:00 EST 2018

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1485387

Report Number(s):: LA-UR-17-24604
Journal ID: ISSN 2100-014X

Grant/Contract Number:: 89233218CNA000001

Resource Type:: Accepted Manuscript

Journal Name:: EPJ Web of Conferences (Online)

Additional Journal Information:: Journal Name: EPJ Web of Conferences (Online); Journal Volume: 193; Conference: 6th Workshop on Nuclear Fission and Spectroscopy of Neutron-Rich Nuclei, Chamrousse (France), 20-24 Mar 2017; Journal ID: ISSN 2100-014X

Publisher:: EDP Sciences

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

Citation Formats


                    Kelly, Keegan John, Devlin, Matthew James, Gomez, Jaime A., O'Donnell, John M., Taddeucci, Terry Nicholas, Haight, Robert Cameron, Lee, Hye Young, Mosby, Shea Morgan, Fotiadis, Nikolaos, Neudecker, Denise, Talou, Patrick, Rising, Michael Evan, White, Morgan Curtis, Solomon, Clell Jeffrey Jr., Wu, Ching-Yen, Bucher, Brian Michael, Buckner, Matthew Quinn, and Henderson, Roger Alan. Measurements of the Prompt Fission Neutron Spectrum at LANSCE: The Chi-Nu Experiment.  United States: N. p., 2018. 
Web.  doi:10.1051/epjconf/201819303003.

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                    Kelly, Keegan John, Devlin, Matthew James, Gomez, Jaime A., O'Donnell, John M., Taddeucci, Terry Nicholas, Haight, Robert Cameron, Lee, Hye Young, Mosby, Shea Morgan, Fotiadis, Nikolaos, Neudecker, Denise, Talou, Patrick, Rising, Michael Evan, White, Morgan Curtis, Solomon, Clell Jeffrey Jr., Wu, Ching-Yen, Bucher, Brian Michael, Buckner, Matthew Quinn, & Henderson, Roger Alan. Measurements of the Prompt Fission Neutron Spectrum at LANSCE: The Chi-Nu Experiment.  United States.  https://doi.org/10.1051/epjconf/201819303003

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                    Kelly, Keegan John, Devlin, Matthew James, Gomez, Jaime A., O'Donnell, John M., Taddeucci, Terry Nicholas, Haight, Robert Cameron, Lee, Hye Young, Mosby, Shea Morgan, Fotiadis, Nikolaos, Neudecker, Denise, Talou, Patrick, Rising, Michael Evan, White, Morgan Curtis, Solomon, Clell Jeffrey Jr., Wu, Ching-Yen, Bucher, Brian Michael, Buckner, Matthew Quinn, and Henderson, Roger Alan. Wed .  
"Measurements of the Prompt Fission Neutron Spectrum at LANSCE: The Chi-Nu Experiment".  United States.  https://doi.org/10.1051/epjconf/201819303003.  https://www.osti.gov/servlets/purl/1485387.

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@article{osti_1485387,

  title        = {Measurements of the Prompt Fission Neutron Spectrum at LANSCE: The Chi-Nu Experiment},

  author       = {Kelly, Keegan John and Devlin, Matthew James and Gomez, Jaime A. and O'Donnell, John M. and Taddeucci, Terry Nicholas and Haight, Robert Cameron and Lee, Hye Young and Mosby, Shea Morgan and Fotiadis, Nikolaos and Neudecker, Denise and Talou, Patrick and Rising, Michael Evan and White, Morgan Curtis and Solomon, Clell Jeffrey Jr. and Wu, Ching-Yen and Bucher, Brian Michael and Buckner, Matthew Quinn and Henderson, Roger Alan},

  abstractNote = {The goal of the Chi-Nu experiment at the Los Alamos Neutron Science Center is to measure the prompt fission neutron spectra from major actinides using a double time-of-flight method with a pulsed, white incoming neutron source. Fission events are detected with a parallel-plate avalanche counter and outgoing neutrons are detected with either a 6Li-glass or liquid scintillator detector array for low- or high-energy neutrons, respectively. A detector response matrix for the interaction of neutrons with the experimental environment for neutrons measured with the Chi-Nu 6Li-glass detector array has been calculated to obtain a full understanding of the measured Chi-Nu data and also to allow for nearly instantaneous production of simulated Chi-Nu data spectra. Prompt fission neutron spectra corresponding to 19 incoming neutron energy ranges from 0.7-20 MeV have been extracted using the ratio-of-ratios method with Chi-Nu 6Li-glass data on the neutron-induced fission of 235U.},

  doi          = {10.1051/epjconf/201819303003},

  journal      = {EPJ Web of Conferences (Online)},

  number       = ,

  volume       = 193,

  place        = {United States},

  year         = {Wed Nov 14 00:00:00 EST 2018},

  month        = {Wed Nov 14 00:00:00 EST 2018}

}

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https://doi.org/10.1051/epjconf/201819303003

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Cited by: 6 works

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Figures / Tables:

Figure 1: An example ⁶Li-glass spectrum as a function of E_t , the energy determined from the neutron time of flight. These data correspond to prompt fission neutrons emitted from the neutron-induced fission of ²³⁵U for an incoming neutron energy range of 1.0 MeV ≤ E$inc\atop{n}$ ≤ 1.5 MeV. Themore »

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Works referenced in this record:

The LANL/LLNL Prompt Fission Neutron Spectrum Program at LANSCE and Approach to Uncertainties
journal, January 2015

Haight, R. C.; Wu, C. Y.; Lee, H. Y.
Nuclear Data Sheets, Vol. 123
DOI: 10.1016/j.nds.2014.12.023

Numerical integration of detector response functions via Monte Carlo simulations
journal, September 2017

Kelly, K. J.; O’Donnell, J. M.; Gomez, J. A.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 866
DOI: 10.1016/j.nima.2017.05.048

The Need for Precise and Well-documented Experimental Data on Prompt Fission Neutron Spectra from Neutron-induced Fission of 239Pu
journal, January 2016

Neudecker, D.; Taddeucci, T. N.; Haight, R. C.
Nuclear Data Sheets, Vol. 131
DOI: 10.1016/j.nds.2015.12.005

Multiple-scattering Corrections to Measurements of the Prompt Fission Neutron Spectrum
journal, January 2015

Taddeucci, T. N.; Haight, R. C.; Lee, H. Y.
Nuclear Data Sheets, Vol. 123
DOI: 10.1016/j.nds.2014.12.024

ENDF/B-VII.1 Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields and Decay Data
journal, December 2011

Chadwick, M. B.; Herman, M.; Obložinský, P.
Nuclear Data Sheets, Vol. 112, Issue 12
DOI: 10.1016/j.nds.2011.11.002

Li-glass detector response study with a 252Cf source for low-energy prompt fission neutrons
journal, March 2013

Lee, H. Y.; Taddeucci, T. N.; Haight, R. C.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 703
DOI: 10.1016/j.nima.2012.10.137

A new method to reduce the statistical and systematic uncertainty of chance coincidence backgrounds measured with waveform digitizers
journal, January 2016

O׳Donnell, J. M.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 805
DOI: 10.1016/j.nima.2015.07.044

A multiple parallel-plate avalanche counter for fission-fragment detection
journal, September 2015

Wu, C. Y.; Henderson, R. A.; Haight, R. C.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 794
DOI: 10.1016/j.nima.2015.05.010

Energy Spectrum of Neutrons from Thermal Fission of $U^{235}$
journal, September 1952

Watt, B. E.
Physical Review, Vol. 87, Issue 6
DOI: 10.1103/PhysRev.87.1037

A new method to reduce the statistical and systematic uncertainty of chance coincidence backgrounds measured with waveform digitizers
text, January 2016

O'Donnell, J. M.
arXiv
DOI: 10.48550/arxiv.1611.06240

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The ²³⁵U prompt fission neutron spectrum measured by the Chi-Nu project at LANSCE

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Similar Records

Title: Measurements of the Prompt Fission Neutron Spectrum at LANSCE: The Chi-Nu Experiment

Abstract

Citation Formats

Figures / Tables:

The LANL/LLNL Prompt Fission Neutron Spectrum Program at LANSCE and Approach to Uncertainties journal, January 2015

Numerical integration of detector response functions via Monte Carlo simulations journal, September 2017

The Need for Precise and Well-documented Experimental Data on Prompt Fission Neutron Spectra from Neutron-induced Fission of 239Pu journal, January 2016

Multiple-scattering Corrections to Measurements of the Prompt Fission Neutron Spectrum journal, January 2015

ENDF/B-VII.1 Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields and Decay Data journal, December 2011

Li-glass detector response study with a 252Cf source for low-energy prompt fission neutrons journal, March 2013

A new method to reduce the statistical and systematic uncertainty of chance coincidence backgrounds measured with waveform digitizers journal, January 2016

A multiple parallel-plate avalanche counter for fission-fragment detection journal, September 2015

Energy Spectrum of Neutrons from Thermal Fission of U 235 journal, September 1952

A new method to reduce the statistical and systematic uncertainty of chance coincidence backgrounds measured with waveform digitizers text, January 2016

The LANL/LLNL Prompt Fission Neutron Spectrum Program at LANSCE and Approach to Uncertainties
journal, January 2015

Numerical integration of detector response functions via Monte Carlo simulations
journal, September 2017

The Need for Precise and Well-documented Experimental Data on Prompt Fission Neutron Spectra from Neutron-induced Fission of 239Pu
journal, January 2016

Multiple-scattering Corrections to Measurements of the Prompt Fission Neutron Spectrum
journal, January 2015

ENDF/B-VII.1 Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields and Decay Data
journal, December 2011

Li-glass detector response study with a 252Cf source for low-energy prompt fission neutrons
journal, March 2013

A new method to reduce the statistical and systematic uncertainty of chance coincidence backgrounds measured with waveform digitizers
journal, January 2016

A multiple parallel-plate avalanche counter for fission-fragment detection
journal, September 2015

Energy Spectrum of Neutrons from Thermal Fission of $U^{235}$
journal, September 1952

A new method to reduce the statistical and systematic uncertainty of chance coincidence backgrounds measured with waveform digitizers
text, January 2016