skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on March 15, 2019

Title: Hauser-Feshbach fission fragment de-excitation with calculated macroscopic-microscopic mass yields

The Hauser-Feshbach statistical model is applied to the de-excitation of primary fission fragments using input mass yields calculated with macroscopic-microscopic models of the potential energy surface. We test the sensitivity of the prompt fission observables to the input mass yields for two important reactions, 235U (n th, f) and 239Pu (n th, f) , for which good experimental data exist. General traits of the mass yields, such as the location of the peaks and their widths, can impact both the prompt neutron and γ-ray multiplicities, as well as their spectra. Specifically, we use several mass yields to determine a linear correlation between the calculated prompt neutron multiplicity $$\bar{v}$$ and the average heavy-fragment mass $$\langle$$A h$$\rangle$$ of the input mass yields ∂$$\bar{v}$$/∂ $$\langle$$A h$$\rangle$$ = ± 0.1 (n / f )/u . The mass peak width influences the correlation between the total kinetic energy of the fission fragments and the total number of prompt neutrons emitted, $$\bar{v}_T$$ ( TKE ) . Finally, typical biases on prompt particle observables from using calculated mass yields instead of experimental ones are δ$$\bar{v}$$ = 4 % for the average prompt neutron multiplicity, δ$$\overline{M}_γ$$ = 1% for the average prompt γ-ray multiplicity, δ$$\bar{ε}$$ $$LAB\atop{n}$$ = 1 % for the average outgoing neutron energy, δ$$\bar{ε}_γ$$ = 1 % for the average γ-ray energy, and δ $$\langle$$TKE$$\rangle$$ = 0.4 % for the average total kinetic energy of the fission fragments.
Authors:
ORCiD logo [1] ;  [1] ;  [1] ; ORCiD logo [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Report Number(s):
LA-UR-17-31000
Journal ID: ISSN 2469-9985; PRVCAN
Grant/Contract Number:
AC52-06NA25396
Type:
Accepted Manuscript
Journal Name:
Physical Review C
Additional Journal Information:
Journal Volume: 97; Journal Issue: 3; Journal ID: ISSN 2469-9985
Publisher:
American Physical Society (APS)
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Atomic and Nuclear Physics
OSTI Identifier:
1440483
Alternate Identifier(s):
OSTI ID: 1426328