Thesis (Ph.D) - University of Birmingham, School of Physics and Space Research, 1992.
|Statement||by Saeed Murtaza.|
The use of fast neutron radiography using accelerator neutron sources offers a number of advantages over the conventional thermal technique. Such a system is complex, with many different variables in terms of the generation and detection of the neutrons and the geometry of the imaging. Computational models have been developed in order to allow different systems Cited by: 4. We present new experimental evidence supporting the technique of fast neutron resonance radiography (NRR). Using a set of neutron attenuation images collected at several different neutron energies, the images can be transformed into a set of elemental maps, indicating the presence and relative quantity of a fixed set of basis elements. Here we report on the . Imaging was performed at the RAD beamline (radial channel number 2) of the 10 MW research reactor of the BNC (Tozser, ) shown in Fig. beamline is routinely utilized for thermal neutron imaging featuring a thermal flux of around 4e7 cm −2 s − beam features further a significant gamma background of Gy/h (non-attenuated) and a significant fast neutron Cited by: The idea of this article is to use an isotropic illumination of a sample by thermal neutrons instead of a collimated beam for imaging purposes. The standard experimental setup is rearranged: the inspected object is placed to an isotropic field of slow neutrons and observed by a pinhole camera with an imaging neutron detector. A fraction of neutrons scattered inside of the .
The feasibility of integration of photon and neutron radiography for nondestructive detection of illicit materials was examined. The MCNP5 code was used to model a radiography system consisting of accelerator-based neutron and photon sources and the imaging detector array, with an object under scrutiny placed between them. T based 14 MeV neutrons. Various issues related to fast neutron radiography are still under study such as source intensity requirement, optimum collimator design, sensitive imaging system and reduction in fast neutron scattering from surrounding materials or from object itself to improve image quality. An experimental study on fast neutron radiography The aim was to develop an FNR system with a moderate intensity neutron source for imaging of specimen containing mixed low-Z and high-Z materials. The experimental set-up consists of a D-T neutron generator, collimator and an EMCCD camera based imaging system. E., et al.: Neutron. Due to the high installation cost, the safety concern and the immobility of the research reactors, the neutron radiography system based on portable neutron generator is proposed. Since the neutrons generated from a portable neutron generator are mostly the fast neutrons, the system is emphasized on using the fast neutrons for the purpose of conducting the radiography.
A number of fast-neutron radiography systems have been reported using either high-energy accelerator-based neutron sources or commercial 14 MeV neutron generators. These include: A gamma-ray and neutron radiography system was developed by Ancore Corporation (Rynes et al., ; Loveman et al., ) to provide supplemental information . Hydrogen-charged supermartensitic steel samples were used to systematically investigate imaging artifacts in neutron radiography. Cadmium stencils were placed around the samples to shield the scintillator from excessive neutron radiation and to investigate the influence of the backlight effect. The contribution of scattered neutrons to the total detected intensity was . Neutron radiography has flourished at reactor facilities for more than four decades and is relatively new to accelerator-based neutron sources. Recent advances in neutron source and detector technologies, such as the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, TN, and the microchannel plate (MCP. Studies were carried out for the design of a thermal, an epithermal, and a fast neutron beam for neutron radiography (NRG) in the horizontal beam port or .