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Title: Sensitivity of an (α,n) neutron source to (α,n) cross sections and stopping powers

Journal Article · · Annals of Nuclear Energy (Oxford)
 [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

The first-order sensitivities of the (α,n) neutron source rate density in a homogeneous material to isotopic (α,n) cross sections, elemental electronic stopping power data, and general coefficients for the nuclear stopping power are derived for the total neutron source and the energy-dependent neutron source. The physics bases for some of the equations in the SOURCES4C calculation of the stopping power are briefly discussed. The derivatives have been implemented in SOURCES4C. In simple PuO2 and PuB2 test problems, the computed derivatives compare extremely well with central differences. As a result, the first-order sensitivities are applied to show that improving the value of one of SOURCES4C’s stopping-power coefficients changes the (α,n) neutron source rate by 1.738 × 10–6% in the PuO2 problem.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA). Office of Defense Nuclear Nonproliferation R&D (NA-22); USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
89233218CNA000001
OSTI ID:
1604039
Alternate ID(s):
OSTI ID: 2325475
Report Number(s):
LA-UR-19-27042; TRN: US2104185
Journal Information:
Annals of Nuclear Energy (Oxford), Vol. 138, Issue C; ISSN 0306-4549
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

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