Neutron source reconstruction of one-dimensional neutron images through maximum likelihood methods

The one-dimensional imager of neutrons (ODIN) has been used to image neutrons emitted from the source of Magnetized Liner Inertial Fusion (MagLIF) experiments on the Z facility. These experiments produce DD-neutrons which pass through a 100-mm thick tungsten rolled edge slit to then be imaged on CR-39 detectors. A piece of high-density polyethylene is used as a neutron to proton convertor to improve the CR-39 detection efficiency. The latent tracks within the CR-39 are exposed using a chemical etching process and recorded using an optical scanning system. The data, consisting of track diameter, eccentricity, position, and contrast, is down selected for primary DD-neutrons expected to have traveled directly from the through the slit assemble to the detector. The selected data is binned and integrated along the resolving axis to produce an axial detector response. A mathematical model of the instrument response function has been developed which is used with existing ODIN data to perform neutron source profile recovery via a maximum likelihood method assuming Gaussian noise.

SAND No: SAND2022-8799 A

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