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Lawrence Livermore National Laboratory (LLNL) is developing a high-brightness, quasi-monoenergetic neutron source for fast neutron-based imaging. The intensity of the neutron source is expected to be 10 10∼11 n/s/sr with energies set at 7 MeV or 10 MeV with 5% bandwidth at 0-degrees. The neutrons are produced by the D(d,n) reaction using one of two accelerators of consisting of 1 or 2 RFQs (depending on the desired energy) and a DTL. Each accelerator will deliver approximately 100- or 300-uA (depending on the energy) average current deuteron beam onto a pulsed deuterium gas target or a solid target, depending on the application. In this paper, we discuss some of our benchmarking measurements and overall progress in preparation to be online in late 2017. We also discuss our performance expectations and broader set of applications.

Permanent magnets containing rare earth elements (REEs) such as Dysprosium and Neodymium offer an advantage over non-REE containing magnets (e.g. ferrite or AlNiCo) in terms of power relative to size. However, REE availability has varied significantly in recent years leading to volatility in the cost of rare earth permanent magnets (REPMs). The supply of REEs can be increased by recycling consumer products and industrial machinery that contain REPMs at product end-of-life (EOL). This paper discusses the REE recovery process for EOL products. The optimal dismantling of products is examined with an emphasis placed on obtaining used REPMs. The challenge of collecting, managing, transporting, and processing used products is addressed through the development of a cost model for REPM recovery. This model is used to investigate several EOL strategies for recovering REPMs. Sensitivity analysis is conducted to identify the key factors that influence value recovery economics. A hard disk drive serves as a case study for model demonstration.

International Linear Collider (ILC) interaction region beam sizes and component position stability requirements will likely be as small as a few nanometers. It is important to the ILC design effort to demonstrate that these tolerances can be achieved–ideally using a beam-based stability measurement. We developed a high resolution RF cavity Beam Position Monitor (BPM) system. A triplet of these BPMs, installed in the extraction line of the KEK Accelerator Test Facility (ATF) and tested with its ultra-low emittance beam, achieved a position measurement resolution of 15 nm. A metrology system for the three BPMs was subsequently installed. This system employed optical encoders to measure each BPM's position and orientation relative to a zero-coefficient of thermal expansion carbon fiber frame. We have demonstrated that the three BPMs behave as a rigid-body at the level of less than 5 nm.

As part of the ongoing development of fast neutron imaging technology for national security applications at LLNL, a large-format imaging optics system is being designed and built. The system will be used to acquire radiographic images of heavily-shielded low-Z objects irradiated by ~10 MeV neutrons and is expected to have an ultimate spatial resolution ~1 mm (FWHM). It is comprised of a 65 cm times 65 cm plastic scintillator (e.g. BC-408), an aluminized front-surface turning mirror and a fast (~f/1.25) optical lens coupled to a CCD camera body with a cryo-cooled, back-illuminated 4096 times 4096 (15 mum) pixel sensor. The lens and camera were developed and purchased from vendors and system integration is being done at LLNL. A description of the overall system and its projected performance characteristics shall be presented.

3 pp. (2007)., International Linear Collider (ILC) interaction region beam sizes and component position stability requirements will be as small as a few nanometers. It is important to the ILC design effort to demonstrate that these tolerances can be achieved - ideally using beam-based stability measurements. It has been estimated that RF cavity beam position monitors (BPMs) could provide position measurement resolutions of less than one nanometer and could form the basis of the desired beam-based stability measurement. We have developed a high resolution RF cavity BPM system. A triplet of these BPMs has been installed in the extraction line of the KEK Accelerator Test Facility (ATF) for testing with its ultra-low emittance beam. A metrology system for the three BPMs was recently installed. This system employed optical encoders to measure each BPM's position and orientation relative to a zero-coefficient of thermal expansion carbon fiber frame and has demonstrated that the three BPMs behave as a rigid-body to less than 5 nm. To date, we have demonstrated a BPM resolution of less than 20 nm over a dynamic range of +/- 20 microns.

We are proceeding with the development of a high-energy (10 MeV) neutron imaging system for use as an inspection tool in nuclear stockpile stewardship applications. Our goal is to develop and deploy an imaging system capable of detecting cubic-mm-scale voids, cracks or other significant structural defects in heavily-shielded low-Z materials within nuclear device components. The final production-line system will be relatively compact (suitable for use in existing or proposed facilities within the DOE complex) and capable of acquiring both radiographic and tomographic (CT) images. In this report, we will review our programmatic accomplishments to date, highlighting recent (FY06) progress on engineering and technology development issues related to the proposed imaging system. We will also discuss our preliminary project plan for FY07, including engineering initiatives, proposed radiation damage experiments (neutrons and x rays) and potential options for conducting classified neutron imaging experiments at LLNL.

This paper provides an overview of a new approach to the measurement of software. The measurements are based on the count of operators and operands contained in a program. The measurement methodologies are consistent across programming language barriers. Practical significance is discussed, and areas are identified for additional research and validation.