A kinematically complete, interdisciplinary, and co-institutional measurement of the ¹⁹F(α,n) cross section for nuclear safeguards science

Technical Report · Sun May 01 00:00:00 EDT 2016

DOI:https://doi.org/10.2172/1263500· OSTI ID:1263500

Peters, W. A. ^[1]; Smith, M. S. ^[2]; Pittman, S. ^[2]; Thompson, S. J. ^[3]; Clement, R. R. C. ^[3]; Cizewski, J. A. ^[4]; Pain, S. D. ^[2]; Febbraro, M. ^[5]; Chipps, K. A. ^[2]; Burcher, S. ^[4]; Manning, B. ^[4]; Reingold, C. ^[4]; Avetisyan, R. ^[6]; Battaglia, A. ^[6]; Chen, Y. ^[6]; Long, A. ^[6]; Lyons, S. ^[6]; Marley, S. T. ^[6]; Seymour, C. ^[6]; Siegl, K. T. ^[6] ; Smith, M. K. ^[6]; Strauss, S. ^[6]; Talwar, R. ^[6]; Bardayan, D. W. ^[6]; Gyurjinyan, A. ^[6]; Smith, K. ^[7]; Thornsberry, C.; Thompson, P.; Madurga, M. ^[7]; Stech, E. ^[6]; Tan, W. P. ^[6]; Wiescher, M. ^[6]; Ilyushkin, S. ^[8]; Tully, Z. ^[9]; Grinder, M. M. ^[3]

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1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
3. Idaho National Lab. (INL), Idaho Falls, ID (United States)
4. Rutgers Univ., New Brunswick, NJ (United States)
5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Michigan, Ann Arbor, MI (United States)
6. Univ. of Notre Dame, IN (United States)
7. Univ. of Tennessee, Knoxville, TN (United States)
8. Colorado School of Mines, Golden, CO (United States)
9. Tennessee Technological Univ., Cookeville, TN (United States)

Alpha particles emitted from the decay of uranium in a UF₆ matrix can interact with fluorine and generate neutrons via the ¹⁹F(α,n)²²Na reaction. These neutrons can be used to determine the uranium content in a UF₆ storage cylinder. The accuracy of this self-interrogating, non-destructive assay (NDA) technique is, however, limited by the uncertainty of the ¹⁹F(α,n)²²Na cross section. We have performed complementary measurements of the ¹⁹F(α,n)²²Na reaction with both ⁴He and ¹⁹F beams to improve the precision of the ¹⁹F(α,n)²²Na cross section over the alpha energy range that encompasses common actinide alpha decay needed for NDA studies. We have determined an absolute cross section for the ¹⁹F(α,n)²²Na reaction to an average precision of 7.6% over the alpha energy range of 3.9 – 6.7 MeV. We utilized this cross section in a simulation of a 100 g spherical UF₆ assembly and obtained a change in neutron emission rate values of approximately 10-12%, and a significant (factor of 3.6) decrease in the neutron emission rate uncertainty (from 50-51% to 13-14%), compared to simulations using the old cross section. Our new absolute cross section enables improved interpretations of NDAs of containers of arbitrary size and configuration.

• Research Organization: Idaho National Lab. (INL), Idaho Falls, ID (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation
• Contributing Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rutgers Univ., New Brunswick, NJ (United States); Univ. of Notre Dame, IN (United States); Univ. of Tennessee, Knoxville, TN (United States)
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 1263500
• Report Number(s): INL/EXT-16-38791; TRN: US1601611
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
SODIUM 22
FLUORINE 19 TARGET
URANIUM HEXAFLUORIDE
ALPHA DECAY
MEV RANGE 01-10
NEUTRONS
NEUTRON EMISSION
SPHERES
EXCITATION FUNCTIONS
ACCURACY
URANIUM
ALPHA REACTIONS
SAFEGUARDS
COMPUTERIZED SIMULATION
GAS CYLINDERS
STORAGE
NUCLEAR REACTION ANALYSIS
COMPOUND-NUCLEUS REACTIONS
F(alpha
n)