Long-Lifetime Low-Scatter Neutron Polarization Target (open access)

Long-Lifetime Low-Scatter Neutron Polarization Target

Polarized neutrons scattering is an important technology for characterizing magnetic and other materials. Polarized helium three (P-3He) is a novel technology for creating polarized beams and, perhaps more importantly, for the analysis of polarization in highly divergent scattered beams. Analysis of scattered beams requires specialized targets with complex geometries to ensure accurate results. Special materials and handling procedures are required to give the targets a long useful lifetime. In most cases, the targets must be shielded from stray magnetic fields from nearby equipment. SRL has developed and demonstrated hybrid targets made from glass and aluminum. We have also developed and calibrated a low-field NMR system for measuring polarization lifetimes. We have demonstrated that our low-field system is able to measure NMR signals in the presence of conducting (metallic) cell elements. We have also demonstrated a non-magnetic valve that can be used to seal the cells. We feel that these accomplishments in Phase I are sufficient to ensure a successful Phase II program. The commercial market for this technology is solid. There are over nine neutron scattering centers in the US and Canada and over 22 abroad. Currently, the US plans to build a new $1.4B scattering facility called the Spallation …
Date: July 9, 2004
Creator: Richardson, Dr. Jonathan M.
System: The UNT Digital Library
Radiation Effects in Nuclear Waste Materials (open access)

Radiation Effects in Nuclear Waste Materials

The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials.
Date: July 9, 2004
Creator: Weber, William j.; Wang, Lumin & Icenhower, Jonathan
System: The UNT Digital Library
Ground Control for Emplacement Drifts for LA (open access)

Ground Control for Emplacement Drifts for LA

The purpose of this calculation is to analyze the stability of repository emplacement drifts during the preclosure period, and to provide a final ground support method for emplacement drifts for the License Application (LA). The scope of the work includes determination of input parameter values and loads, selection of appropriate process and methods for the calculation, application of selected methods, such as empirical or analytical, to the calculation, development and execution of numerical models, and evaluation of results. Results from this calculation are limited to use for design of the emplacement drifts and the final ground support system installed in these drifts. The design of non-emplacement openings and their ground support systems is covered in the ''Ground Control for Non-Emplacement Drifts for LA'' (BSC 2004c).
Date: July 9, 2004
Creator: Sun, Y.
System: The UNT Digital Library
Intrinisc Angular and Energy Resolution of Electron-Tracking Detectors (open access)

Intrinisc Angular and Energy Resolution of Electron-Tracking Detectors

The purpose of this study was to estimate the intrinsic physics limitations on the angular and energy resolution of electron-tracking type gamma-ray detectors. In a Compton interaction, one can completely determine the direction and energy of the incoming gamma ray, without measuring the scattered photon's energy, if one can measure the direction and energy of the scattered electron, and the direction of the scattered photon. Multiple scattering of the Compton electron will quickly destroy the information of the electron's initial direction, so practical devices must be able to resolve the original electron direction, i.e., have tracking resolution mucic h smaller than the typical radiation length in the material.
Date: July 9, 2004
Creator: Gronberg, J B; Johnson, S C; Lange, D J & Wright, D M
System: The UNT Digital Library
Study of Compton vs. Photoelectric Interactions (open access)

Study of Compton vs. Photoelectric Interactions

We have studied how often incoming photons interact via a Compton interaction and/or a photoelectric interaction as a function of energy and detector material Results are using a 1m{sup 3} detector, and discrete energy photons from 0.1 MeV up to 10 MeV. Essentially all of the lower energy photons interact at least once in a detector of this size. This is not the case at higher energies. Each detector, photon energy combination was simulated with 2000 photons.
Date: July 9, 2004
Creator: Gronberg, J B; Johnson, S C; Lange, D J; Wright, D M & Beiersdorfer, P
System: The UNT Digital Library
Study of the Uncertainty on Compton Ring Reconstruction (open access)

Study of the Uncertainty on Compton Ring Reconstruction

The purpose of this study was to estimate the effect of measurement errors in the position and energy of the observed interactions on the angular resolution of a Compton-ring imaging type detector. In a Compton interaction, if one can measure the energy of the scattered photon and the energy of the Compton electron, then one can determine the scattering angle between the incoming and outgoing photon using the well-known Compton formula.
Date: July 9, 2004
Creator: Gronberg, J B; Johnson, S C; Lange, D J & Wright, D M
System: The UNT Digital Library
Technical Scope and Approach for the 2004 Composite Analysis of Low Level Waste Disposal at the Hanford Site (open access)

Technical Scope and Approach for the 2004 Composite Analysis of Low Level Waste Disposal at the Hanford Site

A composite analysis is required by U.S. Department of Energy (DOE) Manual 435.1-1 to ensure public safety through the management of active and planned low-level radioactive waste disposal facilities associated with the Hanford Site (DOE/HQ-Manual 435.1-1). A Composite Analysis is defined as ''a reasonably conservative assessment of the cumulative impact from active and planned low-level waste disposal facilities, and all other sources from radioactive contamination that could interact with the low-level waste disposal facility to affect the dose to future members of the public''. At the Hanford Site, a composite analysis is required for continued disposal authorization for the immobilized low-activity waste, tank waste vitrification plant melters, low level waste in the 200 East and 200 West Solid Waste Burial Grounds, and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) waste in the Environmental Restoration Disposal Facility. The 2004 Composite Analysis will be a site-wide analysis, considering final remedial actions for the Columbia River corridor and the Central Plateau at the Hanford Site. The river corridor includes waste sites and facilities in each of the 100 Areas as well as the 300, 400, and 600 Areas. The remedial actions for the river corridor are being conducted to meet residential land …
Date: July 9, 2004
Creator: Kincaid, Charles T.; Bryce, Robert W. & Buck, John W.
System: The UNT Digital Library