Fusion-neutron-yield, activation measurements at the Z accelerator: Design, analysis, and sensitivity

Journal Article · Tue Apr 15 00:00:00 EDT 2014 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4870779· OSTI ID:22254927

Ruiz, C. L.; Fehl, D. L.; Chandler, G. A.; Knapp, P. F.; Smelser, R. M.; Torres, J. A. ^[1]; Cooper, G. W.; Nelson, A. J. ^[2]; Leeper, R. J. ^[3]

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1. Sandia National Laboratories, Diagnostics and Target Physics, Albuquerque, New Mexico 87123 (United States)
2. Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States)
3. Los Alamos National Laboratories, Plasma Physics Group, Los Alamos, New Mexico 87545 (United States)

We present a general methodology to determine the diagnostic sensitivity that is directly applicable to neutron-activation diagnostics fielded on a wide variety of neutron-producing experiments, which include inertial-confinement fusion (ICF), dense plasma focus, and ion beam-driven concepts. This approach includes a combination of several effects: (1) non-isotropic neutron emission; (2) the 1/r{sup 2} decrease in neutron fluence in the activation material; (3) the spatially distributed neutron scattering, attenuation, and energy losses due to the fielding environment and activation material itself; and (4) temporally varying neutron emission. As an example, we describe the copper-activation diagnostic used to measure secondary deuterium-tritium fusion-neutron yields on ICF experiments conducted on the pulsed-power Z Accelerator at Sandia National Laboratories. Using this methodology along with results from absolute calibrations and Monte Carlo simulations, we find that for the diagnostic configuration on Z, the diagnostic sensitivity is 0.037% ± 17% counts/neutron per cm{sup 2} and is ∼ 40% less sensitive than it would be in an ideal geometry due to neutron attenuation, scattering, and energy-loss effects.

• OSTI ID: 22254927
• Journal Information: Review of Scientific Instruments, Vol. 85, Issue 4; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
ATTENUATION
COMPUTERIZED SIMULATION
COPPER
DEUTERIUM
ENERGY LOSSES
INERTIAL CONFINEMENT
MONTE CARLO METHOD
NEUTRON DIFFRACTION
NEUTRON EMISSION
NEUTRON FLUENCE
PLASMA FOCUS
SANDIA NATIONAL LABORATORIES
SENSITIVITY
TRITIUM