There is great concern that the short, intense XFEL pulse of the LCLS will damage the optics that will be placed into the beam. We have analyzed the extent of the problem by considering the anticipated materials and position of the optical components in the beam path, calculated the absorbed dose as a function of photon energy, and compared these doses with the expected doses required (i) to observe rapid degradation due to thermal fatigue, (ii) to reach the melting temperature, or (iii) to actually melt the material. We list the materials that are anticipated to be placed into the Linac Coherent Light Source (LCLS) x-ray free electron laser (XFEL) beam line, their positions, and the absorbed dose, and compare this dose with anticipated damage thresholds.

A primary purpose of computational models is to inform design decisions and, in order to make those decisions reliably, the confidence in the results of such models must be estimated. Monte Carlo neutron transport models are common tools for reactor designers. These types of models contain several sources of uncertainty that propagate onto the model predictions. Two uncertainties worthy of note are (1) experimental and evaluation uncertainties of nuclear data that inform all neutron transport models and (2) statistical counting precision, which all results of a Monte Carlo codes contain. Adjoint-based implicit uncertainty analyses allow for the consideration of any number of uncertain input quantities and their effects upon the confidence of figures of merit with only a handful of forward and adjoint transport calculations. When considering a rich set of uncertain inputs, adjoint-based methods remain hundreds of times more computationally efficient than Direct Monte-Carlo methods. The LIFE (Laser Inertial Fusion Energy) engine is a concept being developed at Lawrence Livermore National Laboratory. Various options exist for the LIFE blanket, depending on the mission of the design. The depleted uranium hybrid LIFE blanket design strives to close the fission fuel cycle without enrichment or reprocessing, while simultaneously achieving high discharge …

Automation of the LCLS undulator tuning offers many advantages to the project. Automation can make a substantial reduction in the amount of time the tuning takes. Undulator tuning is fairly complex and automation can make the final tuning less dependent on the skill of the operator. Also, algorithms are fixed and can be scrutinized and reviewed, as opposed to an individual doing the tuning by hand. This note presents algorithms implemented in a computer program written for LCLS undulator tuning. The LCLS undulators must meet the following specifications. The maximum trajectory walkoff must be less than 5 {micro}m over 10 m. The first field integral must be below 40 x 10{sup -6} Tm. The second field integral must be below 50 x 10{sup -6} Tm{sup 2}. The phase error between the electron motion and the radiation field must be less than 10 degrees in an undulator. The K parameter must have the value of 3.5000 {+-} 0.0005. The phase matching from the break regions into the undulator must be accurate to better than 10 degrees. A phase change of 113 x 2{pi} must take place over a distance of 3.656 m centered on the undulator. Achieving these requirements is the …

A methodology for modeling gaseous injection has been refined and applied to recent experimental data from the literature. This approach uses a discrete phase analogy to handle gaseous injection, allowing for addition of gaseous injection to a CFD grid without needing to resolve the injector nozzle. This paper focuses on model testing to provide the basis for simulation of hydrogen direct injected internal combustion engines. The model has been updated to be more applicable to full engine simulations, and shows good agreement with experiments for jet penetration and time-dependent axial mass fraction, while available radial mass fraction data is less well predicted.

Considerable interest has been expressed for developing a stable U.S. production capacity for medical isotopes and particularly for molybdenum- 99 (99Mo). This is motivated by recent re-ductions in production and supply worldwide. Consistent with U.S. nonproliferation objectives, any new production capability should not use highly enriched uranium fuel or targets. Conse-quently, Aqueous Homogeneous Reactors (AHRs) are under consideration for potential 99Mo production using low-enriched uranium. Although the Nuclear Regulatory Commission (NRC) has guidance to facilitate the licensing process for non-power reactors, that guidance is focused on reactors with fixed, solid fuel and hence, not applicable to an AHR. A panel was convened to study the technical issues associated with normal operation and potential transients and accidents of an AHR that might be designed for isotope production. The panel has produced the requisite AHR licensing guidance for three chapters that exist now for non-power reactor licensing: Reac-tor Description, Reactor Coolant Systems, and Accident Analysis. The guidance is in two parts for each chapter: 1) standard format and content a licensee would use and 2) the standard review plan the NRC staff would use. This guidance takes into account the unique features of an AHR such as the fuel being in solution; …

The SSRL Gun Test Facility (GTF) was built to develop a high brightness electron injector for the LCLS and has been operational since 1996. Based on longitudinal phase space measurements showing a correlated energy spread the gun was removed and re-characterized in 2002. The low power RF measurements performed on the gun are described below. Perturbative bead measurements were performed to determine the field ratio in the two-cell gun, and network analyzer measurements were made to characterize the mode structure. A second probe was installed to monitor the RF field in the first cell, and a diagnostic was developed to monitor the high-power field ratio. Calibration of the RF probes, a model for analyzing RF measurements, and Superfish simulations of bead and RF measurements are described.

Quadrupoles will be placed between the undulator segments in LCLS to keep the electron beam focused as it passes through. The quadrupoles will be assembled with their respective undulator segments prior to being placed into the tunnel. Beam alignment will be used to center the quadrupoles, along with the corresponding undulators, on the beam. If there is any displacement between the undulator and the quadrupole axes in the assemblies, the beam will deviate from the undulator axis. If it deviates by more than 80{micro}m in vertical or 140{micro}m in horizontal directions, the undulator will not perform as required by LCLS. This error is divided between three sources: undulator axis fiducialization, quadrupole magnetic axis fiducialization, and assembly of the two parts. In particular, it was calculated that the quadrupole needs to be fiducialized to within 25{micro}m in both vertical and horizontal directions. A previous study suggested using a vibrating wire system for finding the magnetic axis of the quadrupoles. The study showed that the method has high sensitivity (up to 1{micro}m) and laid out guidelines for constructing such a system. There are 3 steps in fiducializing the quadrupole with the vibrating wire system. They are positioning the wire at the magnet …

The U.S. Department of Energy (DOE) is responsible for the remediation and long-term stewardship of one of the world's largest groundwater contamination portfolios, with a significant number of plumes containing various contaminants, and considerable total mass and activity. As of 1999, the DOE's Office of Environmental Management was responsible for remediation, waste management, or nuclear materials and facility stabilization at 144 sites in 31 states and one U.S. territory, out of which 109 sites were expected to require long-term stewardship. Currently, 19 DOE sites are on the National Priority List. The total number of contaminated plumes on DOE lands is estimated to be 10,000. However, a significant number of DOE sites have not yet been fully characterized. The most prevalent contaminated media are groundwater and soil, although contaminated sediment, sludge, and surface water also are present. Groundwater, soil, and sediment contamination are present at 72% of all DOE sites. A proper characterization of the contaminant inventory at DOE sites is critical for accomplishing one of the primary DOE missions -- planning basic research to understand the complex physical, chemical, and biological properties of contaminated sites. Note that the definitions of the terms 'site' and 'facility' may differ from one publication …

The Next Generation Retrieval (NGR) project will retrieve suspect transuranic (TRU) waste containers from Trenches 17 and 27 in the 218-E-12B (12B) burial ground. The trenches were in operation from May 1970 through October 1972. A portion of the retrieved containers that will require shipment to and acceptance at a treatment, storage, and disposal (TSD) facility and the containers will be either remote-handled (RH) and/or contact-handled (CH). The method discussed in this document will be used for the RH and some of the CH containers to determine the radionuclide inventory. Waste disposition (shipment and TSD acceptance) requires that the radioactive content be characterized for each container. Source-term estimates using high resolution, shielded, gamma-ray scan assay techniques cannot be performed on a number of RH and other containers with high dose rates from {sup 137}Cs-{sup 137m}Ba. This document provides the method to quantify the radioactive inventory of fission product gamma emitters within the containers based on the surface dose rate measurements taken in the field with hand-held survey instruments.

Beam Finder Wire (BFW) devices will be installed at each break in the Undulator magnet line. These devices will scan small wires across the beam causing some electrons to lose energy through bremsstrahlung. The degraded electrons are subsequently detected downstream of a set of vertical dipole magnets after they pass through the vacuum chamber. This signal can then be used to accurately determine the beam position with respect to the BFW wire. The choice of the wire diameter, scan speed, and operating parameters, depends on the trade-off between the signal size and the radiation damage to the undulator magnets. In this note I estimate the rate of undulator magnet damage that results from scanning as a function of, wire size, scan speed, and average beam current. A separate analysis of the signal size was carried out by Wu. The damage estimate is primarily based on two sources: the first, Fasso, is used to estimate the amount of radiation generated and then absorbed by the magnets; the second, Alderman et. al., is used to estimate the amount of damage the magnet undergoes as a result of the absorbed radiation. Fasso performed a detailed calculation of the radiation, including neutron fluence, that …

In this paper, the authors present several new exact analytic space and time dependent solutions to the problem of magnetic diffusion in R-Z geometry. These problems serve to verify several different elements of an MHD implementation: magnetic diffusion, external circuit time integration, current and voltage energy sources, spatially dependent conductivities, and ohmic heating. The exact solutions are shown in comparison with 2D simulation results from the Ares code.

ICF power plants, such as the LIFE scheme at LLNL, may employ a high-Z, target-chamber gas-fill to moderate the first-wall heat-pulse due to x-rays and energetic ions released during target detonation. To reduce the uncertainties of cooling and beam/target propagation through such gas-filled chambers, we present a pulsed plasma source producing 2-5 eV plasma comprised of high-Z gases. We use a 5-kJ, 100-ns theta discharge for high peak plasma-heating-power, an electrode-less discharge for minimizing impurities, and unobstructed axial access for diagnostics and beam (and/or target) propagation studies. We will report on the plasma source requirements, design process, and the system design.

Complex target structures are necessary to take full advantage of the unique laboratory environment created by inertial confinement fusion experiments. For example, uses-of-ignition targets that contain a thin layer of a low density nanoporous material inside a spherical ablator shell allow placing dopants in direct contact with the DT fuel. The ideal foam for this application is a low-density hydrocarbon foam that is strong enough to survive wetting with cryogenic hydrogen, and low enough in density (density less than {approx}30 mg/cc) to not reduce the yield of the target. Here, we discuss the fabrication foam-lined uses-of-ignition targets, and the development of low-density foams that can be used for this application. Much effort has been directed over the last 20 years toward the development of spherical foam targets for direct-drive and fast-ignition experiments. In these targets, the spherical foam shell is used to define the shape of the cryogenic DT fuel layer, or acts as a surrogate to simulate the cryogenic fuel layer. These targets are fabricated from relatively high-density aerogels (>100 mg/cc) and coated with a few micron thick permeation barrier. With exception of the above mentioned fast ignition targets, the wall of these targets is typically larger than 100 …

The gas leak from the gas attenuator to the main beam line of the Linac Coherent Light Source has been evaluated, with the effect of the Knudsen molecular beam included. It has been found that the gas leak from the gas attenuator of the present design, with nitrogen as a working gas, does not exceed 10{sup -5} torr x l/s even at the highest pressure in the main attenuation cell (20 torr).

We used short lived {sup 239}Np as a yield tracer and state of the art magnetic sector ICP-MS to measure ultra low levels of {sup 237}Np in a number of 'hot wells' at the Nevada National Security Site (NNSS), formerly known as the Nevada Test Site (NTS). The results indicate that {sup 237}Np concentrations at the Almendro, Cambric, Dalhart, Cheshire and Chancellor sites, are in the range of 3 x 10{sup -5} to 7 x 10{sup -2} pCi/L and well below the MCL for alpha emitting radionuclides (15 pCi/L) (EPA, 2009). Thus, while Np transport is believed to occur at the NNSS, activities are expected to be well below the regulatory limits for alpha-emitting radionuclides. We also compared {sup 237}Np concentration data to other radionuclides, including tritium, {sup 14}C, {sup 36}Cl, {sup 99}Tc, {sup 129}I, and plutonium, to evaluate the relative {sup 237}Np transport behavior. Based on isotope ratios relative to published unclassified Radiologic Source Terms (Bowen et al., 1999) and taking into consideration radionuclide distribution between melt glass, rubble and groundwater (IAEA, 1998), {sup 237}Np appears to be substantially less mobile than tritium and other non-sorbing radionuclides, as expected. However, this analysis also suggests that {sup 237}Np mobility is …

Discussion of space-charge effects in a photoluminescence cell that will be used as a nondisruptive total energy monitor at the LCLS facility is presented. Regimes where primary photoelectrons will be confined within the X-ray beam aperture are identified. Effects of the space-charge on the further evolution of the electron and ion populations are discussed. Parameters of the afterglow plasma are evaluated. Conditions under which the detector output will be proportional to the pulse energy are defined.

This note summarizes both the beam-based and various laboratory measurements of quadrupole magnets, units 387 and 428, used for QM02 in the LCLS Injector. These were undertaken because of a consistent discrepancy between accelerator model predictions and beam observations which seemed to indicate a weak QM02. A report 'QM02 Strength Measurement', by Welch and Wu, describes the discrepancy and beam-based measurements on unit 387. Subsequently, unit 387 was replaced by unit 428, refinements were made to analysis of the beam-based measurements were made, and additional magnetic measurements were made on unit 387 in the lab. These new results are summarized in this note. The principle results are: (1) Laboratory measurements of integrated gradient for the same magnet, or for different magnets of the same type, are all within 1% of each other at gradients of interest. These cases cover three independent types of measurements, disassembly/reassembly of the units, and extended periods of time between measurements. (2) Standardization, or lack thereof, can cause integrated gradient errors of approximately 0.2 kG, which can amount to a few percent of the strength of the magnet depending on the setting. (3) Model-independent beam-based measurements indicate the magnets are actually weaker than expected by about …

The laser heater undulator for the LCLS requires different tuning techniques than the main undulators. It is a pure permanent magnet (PPM) undulator, rather than the hybrid design of the main undulators. The PPM design allows analytic calculation of the undulator fields. The calculations let errors be introduced and correction techniques be derived. This note describes how the undulator was modelled, and the methods which were found to correct potential errors in the undulator. The laser heater undulator for the LCLS is a pure permanent magnet device requiring different tuning techniques than the main undulators. In this note, the laser heater undulator is modelled and tuning techniques to compensate various errors are derived.

The objective of this Feasibility Study was to identify the potential of dimmable lighting for providing regulation capacity and contingency reserves if massively-deployed throughout the State. We found that one half of the total electric lighting load in the California commercial sector is bottled up in larger buildings that are greater an 50,000 square feet. Retrofitting large California buildings with dimmable lighting to enable fast DR lighting would require an investment of about $1.8 billion and a"fleet" of about 56 million dimming ballasts. By upgrading the existing installed base of lighting and controls (primarily in large commercial facilities) a substantial amount of ancillary services could be provided. Though not widely deployed, today's state-of-the art lighting systems, control systems and communication networks could be used for this application. The same lighting control equipment that is appropriate for fast DR is also appropriate for achieving energy efficiency with lighting on a daily basis. Thus fast DR can leverage the capabilities that are provided by a conventional dimming lighting control system. If dimmable lighting were massively deployed throughout large California buildings (because mandated by law, for example) dimmable lighting could realistically supply 380 MW of non-spinning reserve, 47percent of the total non-spinning reserves …