Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Sensitivity of neutron observables to the model input in simulations of 252Cf(sf)

Journal Article · · Physical Review C
 [1];  [2];  [3]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Nuclear Science Div.; Univ. of California, Berkeley, CA (United States). Nuclear Engineering Dept.
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Nuclear Theory Group and X-Computational Physics Div.
  3. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Physics Div.; Univ. of California, Davis, CA (United States). Physics Dept.
Within the framework of $FREYA$ event-by-event fission simulations, we study the sensitivity of various neutron observables to the input yield function $$Y$$ ($A,Z,$TKE) on which the fission event sampling is based. We first perform a statistical analysis of the available fission data in order to determine the distribution of possible yield functions $$Y$$ ($A,Z$,TKE) and we then construct a sample of 15,000 such yield functions. For each of these, $FREYA$ is used to generate one million fission events, leading to a corresponding ensemble of fission observables, including the neutron multiplicity distribution and its factorial moments, the neutron energy spectrum, and the neutron-neutron angular correlation. This procedure allows us to study the sensitivity of those neutron observables to the uncertainty in the experimental data. Particular attention is given to the pronounced anticorrelation between the mean neutron multiplicity $$\bar{v}$$ and the mean total fragment kinetic energy TKE. Because the former observable is very well determined experimentally, it is possible to exploit that inherent anticorrelation to derive a significantly stricter tolerance on TKE. In addition, we study the sensitivity to the various $FREYA$ parameters and we introduce a method for determining a A-dependent x parameter, $$x$$($$A$$), based on the measured A-dependent neutron multiplicity, ($$A$$).
Research Organization:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE; USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
AC02-05CH11231; AC52-06NA25396; AC52-07NA27344
OSTI ID:
1560105
Alternate ID(s):
OSTI ID: 1515102
Report Number(s):
LLNL--JRNL-767159; 957515
Journal Information:
Physical Review C, Journal Name: Physical Review C Journal Issue: 5 Vol. 99; ISSN PRVCAN; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (31)

Nuclear-charge distribution and delayed-neutron yields for thermal-neutron-induced fission of 235U, 233U, and 239Pu and for spontaneous fission of 252Cf journal May 1988
Fine structure in the neutron emission ν(A) from 252Cf spontaneous fission fragments journal January 1977
Simultaneous investigation of fission fragments and neutrons in 252Cf (SF) journal December 1988
Investigation of the far asymmetric region in 252Cf(sf) journal May 1997
Fission Reaction Event Yield Algorithm, FREYA — For event-by-event simulation of fission journal June 2015
Fission Reaction Event Yield Algorithm FREYA 2.0.2 journal January 2018
General Description of Fission Observables: GEF Model Code journal January 2016
Evaluation of the Neutron Data Standards journal February 2018
Sensitivity of the 252 Cf(sf) neutron observables to the FREYA input yield functions Y ( A , Z , TKE) journal January 2017
235 U(n, f) Independent fission product yield and isomeric ratio calculated with the statistical Hauser–Feshbach theory journal April 2018
Identifying Inconsistencies in Fission Product Yield Evaluations with Prompt Neutron Emission journal March 2018
Velocity and Angular Distributions of Prompt Neutrons from Spontaneous Fission of Cf 252 journal June 1962
Further Studies of the Prompt Neutrons from the Spontaneous Fission of Cf 252 journal March 1963
Coincident Time-of-Flight Measurements of the Velocities of Cf 252 Fission Fragments journal August 1963
Quantum theory of mechanical deformations journal September 2018
Detailed Study of Alpha Emission in Cf 252 Fission journal January 1973
Fission fragment mass and energy distributions as a function of incident neutron energy measured in a lead slowing-down spectrometer journal January 2010
Investigation of phenomenological models for the Monte Carlo simulation of the prompt fission neutron and γ emission journal November 2010
Advanced Monte Carlo modeling of prompt fission neutrons for thermal and fast neutron-induced fission reactions on Pu 239 journal June 2011
Refined treatment of angular momentum in the event-by-event fission model freya journal April 2014
Prompt neutron multiplicity in correlation with fragments from spontaneous fission of Cf 252 journal December 2014
Improved modeling of photon observables with the event-by-event fission model freya journal December 2017
Hauser-Feshbach fission fragment de-excitation with calculated macroscopic-microscopic mass yields journal March 2018
The CORSET time-of-flight spectrometer for measuring binary products of nuclear reactions journal January 2008
Fission modelling with FIFRELIN journal December 2015
Correlated prompt fission data in transport simulations journal January 2018
Neutron Emission in Fission of 252Cf(SF) journal August 2011
Correlated Prompt Fission Data in Transport Simulations text January 2017
Hauser-Feshbach fission fragment de-excitation with calculated macroscopic-microscopic mass yields text January 2017
Quantum theory of mechanical deformations text January 2018
Evaluation of the Neutron Data Standards text January 2018

Similar Records

Measurement of fragment-correlated γ-ray emission from 252Cf(sf)
Journal Article · Sun May 19 20:00:00 EDT 2024 · Physical Review. C · OSTI ID:2406910

Sensitivity Analysis of Cf-252 (sf) Neutron and Gamma Observables in CGMF
Technical Report · Tue Dec 05 23:00:00 EST 2017 · OSTI ID:1412841