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Visualization of Low-Level Gamma Radiation Sources Using a Low-Cost, High-Sensitivity, Omnidirectional Compton Camera
Published on: January 30, 2020
Diagnosing inertial confinement fusion gamma ray physics (invited)
H W Herrmann1, N Hoffman, D C Wilson
1Los Alamos National Laboratory, P.O. Box 1663, M/S E526, Los Alamos, New Mexico 87545, USA. herrmann@lanl.gov
The gamma reaction history diagnostic measures fusion reactions in inertial confinement fusion experiments. It uses gamma rays to determine key burn parameters and fuel composition for achieving ignition.
Area of Science:
- Nuclear Physics
- Plasma Physics
- Fusion Energy
Background:
- The gamma reaction history (GRH) diagnostic is crucial for inertial confinement fusion (ICF) experiments.
- It provides direct, time-resolved measurements of fusion reaction history.
Purpose of the Study:
- To detail the capabilities of the GRH diagnostic for ICF implosion experiments.
- To highlight its role in determining fundamental burn parameters and fuel composition.
- To explore its application in measuring ablator areal density.
Main Methods:
- Utilizing a multichannel, time-resolved, energy-thresholded gamma-ray spectrometer.
- Detecting 16.75 MeV gamma rays from deuterium-tritium (DT) fusion to measure bang time and burn width.
- Observing 19.8 MeV gamma rays from hydrogen-tritium fusion for fuel composition analysis.
- Measuring 4.43 MeV gamma rays from inelastic neutron scattering on carbon for ablator density.
Main Results:
- The GRH diagnostic enables high-bandwidth, direct measurement of fusion reaction history.
- It is critical for determining fundamental burn parameters like nuclear bang time and burn width.
- Potential for measuring reacting fuel composition and ion temperature using H-T fusion gamma rays.
- Capability to measure ablator areal density through carbon inelastic scattering.
Conclusions:
- The GRH diagnostic is a versatile tool for ICF research, essential for achieving ignition.
- Its multi-gamma-ray detection capabilities offer insights into fusion processes and fuel characteristics.
- GRH measurements are vital for validating ICF models and advancing fusion energy research.
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