skip to main content

Title: Self characterization of a coded aperture array for neutron source imaging

The neutron imaging system at the National Ignition Facility (NIF) is an important diagnostic tool for measuring the two-dimensional size and shape of the neutrons produced in the burning deuterium-tritium plasma during the stagnation stage of inertial confinement fusion implosions. Since the neutron source is small (∼100 μm) and neutrons are deeply penetrating (>3 cm) in all materials, the apertures used to achieve the desired 10-μm resolution are 20-cm long, triangular tapers machined in gold foils. These gold foils are stacked to form an array of 20 apertures for pinhole imaging and three apertures for penumbral imaging. These apertures must be precisely aligned to accurately place the field of view of each aperture at the design location, or the location of the field of view for each aperture must be measured. In this paper we present a new technique that has been developed for the measurement and characterization of the precise location of each aperture in the array. We present the detailed algorithms used for this characterization and the results of reconstructed sources from inertial confinement fusion implosion experiments at NIF.
Authors:
; ; ; ;  [1] ;  [2]
  1. Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)
  2. Livermore National Laboratory, Livermore, California 94550 (United States)
Publication Date:
OSTI Identifier:
22392277
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 85; Journal Issue: 12; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ALGORITHMS; APERTURES; DEUTERIUM; IMPLOSIONS; INERTIAL CONFINEMENT; NEUTRON SOURCES; PLASMA; RESOLUTION; TRITIUM; US NATIONAL IGNITION FACILITY