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This paper compares the results from a GEANT4 simulation of the gas Cherenkov detector 1 (GCD1) with previous simulations and experimental data from the Omega laser facility. The GCD1 collects gammas emitted during a deuterium-tritium capsule implosion and converts them, through several processes, to Cherenkov light. Photon signals are recorded using subnanosecond photomultiplier tubes, producing burn reaction histories. The GEANT4 GCD1 simulation is first benchmarked against ACCEPT, an integrated tiger series code, with good agreement. The simulation is subsequently compared with data from the Omega laser facility, where experiments have been performed to measure the effects of Hohlraum materials on reaction history signals, in preparation for experiments at the National Ignition Facility. [ABSTRACT FROM AUTHOR]

Experiments on the National Ignition Facility (NIF) will require bright, short duration, near-monochromatic x-ray backlighters for radiographic diagnosis of many high-energy density systems. This paper details a vanadium pinhole backlighter producing (1.8±0.5)×1015 x-ray photons into 4π sr near the vanadium He-like characteristic x-ray energy of 5.18 keV. The x-ray yield was quantified from a set of Ross filters imaged to a calibrated image plate, with the Dante diagnostic used to confirm the quasimonochromatic nature of the spectrum produced. Additionally, an x-ray film image shows a source-limited image resolution of 26 μm from a 20 μm diameter pinhole. [ABSTRACT FROM AUTHOR]

This paper describes a common-view disciplined oscillator (CVDO) that locks to a reference time scale through the use of common-view global positioning system (GPS) satellite measurements. The CVDO employs a proportional-integral-derivative controller that obtains near real-time common-view GPS measurements from the internet and provides steering corrections to a local oscillator. A CVDO can be locked to any time scale that makes real-time common-view data available and can serve as a high-accuracy, self-calibrating frequency and time standard. Measurement results are presented where a CVDO is locked to UTC(NIST), the coordinated universal time scale maintained at the National Institute of Standards and Technology in Boulder, Colorado. [ABSTRACT FROM AUTHOR]

Neutrons generated in Inertial Confinement Fusion (ICF) experiments provide valuable information to interpret the conditions reached in the plasma. The neutron time-of-flight (nToF) technique is well suited for measuring the neutron energy spectrum due to the short time (100 ps) over which neutrons are typically emitted in ICF experiments. By locating detectors 10s of meters from the source, the neutron energy spectrum can be measured to high precision. We present a contextual review of the current state of the art in nToF detectors at ICF facilities in the United States, outlining the physics that can be measured, the detector technologies currently deployed and analysis techniques used. [ABSTRACT FROM AUTHOR]

The potential of an x-ray magnifier prepared from a pair of asymmetrically cut crystals is studied to explore high energy x-ray imaging capabilities at high intensity laser facilities. OMEGA-EP and NIF when irradiating mid and high Z targets can be a source of high-energy x-rays whose production mechanisms and use as backlighters are a subject of active research. This paper studies the properties and potential of existing asymmetric cut crystal pairs from the National Institute of Standards and Technology (NIST) built in a new enclosure for imaging x-ray sources. The technique of the x-ray magnifier has been described previously. This new approach is aimed to find a design that could be used at laser facilities by magnifying the x-ray source into a screen far away from the target chamber center, with fixed magnification defined by the crystals' lattice spacing and the asymmetry angles. The magnified image is monochromatic and the imaging wavelength is set by crystal asymmetry and incidence angles. First laboratory results are presented and discussed. [ABSTRACT FROM AUTHOR]

Bang time and reaction history measurements are fundamental components of diagnosing inertial confinement fusion (ICF) implosions and will be essential contributors to diagnosing attempts at ignition on the National Ignition Facility (NIF). Fusion gammas provide a direct measure of fusion interaction rate without being compromised by Doppler spreading. Gamma-based gas Cherenkov detectors that convert fusion gamma rays to optical Cherenkov photons for collection by fast recording systems have been developed and fielded at Omega. These systems have established their usefulness in illuminating ICF physics in several experimental campaigns. Bang time precision better than 25 ps has been demonstrated, well below the 50 ps accuracy requirement defined by the NIF system design requirements. A comprehensive, validated numerical study of candidate systems is providing essential information needed to make a down selection based on optimization of sensitivity, bandwidth, dynamic range, cost, and NIF logistics. This paper presents basic design considerations arising from the two-step conversion process from γ rays to relativistic electrons to UV/visible Cherenkov radiation. [ABSTRACT FROM AUTHOR]

Describes a design study with the objective of optimizing spectral performance of an elliptical wiggler to be installed at the Lawrence Berkeley Laboratory Advanced Light Source in Berkeley, California. Theoretical background; Calculations; Characteristics of an optimum set point for a particular photon energy.

Describes a double-multilayer monochromator designed for the Advanced Photon Source x-ray undulator beamline at Argonne National Laboratory in Argonne, Illinois. Features incorporated in the monochromator design; Water cooling; Vacuum structure.

An Optical Thomson Scattering (OTS) diagnostic is currently being developed for the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. This diagnostic is designed to make measurements of the hohlraum plasma parameters, such as the electron temperature and the density, during inertial confinement fusion (ICF) experiments. NIF ICF experiments present a very challenging environment for optical measurements; by their very nature, hohlraums produce intense soft x-ray emission, which can cause "blanking" (radiation induced opacity) of the radiation facing optical components. The soft x-ray fluence at the surface of the OTS blast shield, 60 cm from the hohlraum, is estimated to be ~8 J cm-2. This is significantly above the expected threshold for the onset of "blanking" effects. A novel xenon plasma x-ray shield is proposed to protect the blast shield from x-rays and mitigate "blanking." Estimates suggest that an areal density of 1019 cm-2 Xe atoms will be sufficient to absorb 99.5% of the soft x-ray flux. Two potential designs for this shield are presented. [ABSTRACT FROM AUTHOR]

Gain can vary across the active area of an x-ray framing camera by a factor of 4 (or more!) due to the voltage loss and dispersion associated with pulse transmission in a microstripline-coated microchannel plate. In order to make quantitative measurements, it is consequently important to measure the gain variation ("flat field"). Moreover, because of electromagnetic cross talk, gain variation depends on specific operational parameters, and ideally a flat field would be obtained at all operating conditions. As part of a collaboration between Lawrence Livermore National Laboratory's National Ignition Facility and the Commissariat à l'Énergie Atomique, we have been able to evaluate the consistency of three different methods of measuring x-ray flat fields. By applying all three methods to a single camera, we are able to isolate performance from method. Here we report the consistency of the methods and discuss systematic issues with the implementation and analysis of each. [ABSTRACT FROM AUTHOR]

In laser based radiation flow experiments, drive variability can often overwhelm the physics sensitivity that one seeks to quantify. Hohlraums can help by providing a more symmetrized, Planckianlike source. However, at higher temperatures, the hohlraum's actual emission can deviate significantly from a truly blackbody, Lambertian source. At the National Ignition Facility (NIF), Dante provides the best quantification of hohlraum output. Unfortunately, limited diagnostic access coupled with NIF's natural symmetry does not allow for Dante measurements at more than two angles. As part of the CEPHEUS campaign on NIF, proof-of-principle experiments to better quantify the gold M-band isotropy were conducted. These experiments positioned beryllium/aluminum mirrors at differing angles, offset from the hohlraum. Filtering removes the thermal emission of the hohlraum and the remaining M-band radiation is preferentially absorbed in the aluminum layer. The subsequent hydrodynamic motion is measured via VISAR. Although indirect, this M-band measurement can be made at any angle. [ABSTRACT FROM AUTHOR]

We have used the EBIT-I electron beam ion trap at the Lawrence Livermore National Laboratory and a duplicate Orion High Resolution X-ray Spectrometer (OHREX) to measure the relative efficiency of a spherically bent quartz (1011) crystal (2d = 6.687 Å) and a spherically bent germanium (111) crystal (2d = 6.532 Å). L-shell X-ray photons from highly charged molybdenum ions generated in EBIT-I were simultaneously focussed and Bragg reflected by each crystal, both housed in a single spectrometer, onto a single CCD X-ray detector. The flux from each crystal was then directly compared. Our results show that the germanium crystal has a reflection efficiency significantly better than the quartz crystal, however, the energy resolution is significantly worse. Moreover, we find that the spatial focussing properties of the germanium crystal are worse than those of the quartz crystal. Details of the experiment are presented, and we discuss the advantages of using either crystal on a streak-camera equipped OHREX spectrometer. [ABSTRACT FROM AUTHOR]

Recent experiments at the Sandia National Laboratory Z facility have called into question models used in calculating opacity, of importance for modeling stellar interiors. An effort is being made to reproduce these results at the National Ignition Facility (NIF). These experiments require a new X-ray opacity spectrometer (OpSpec) spanning 540 eV-2100 eV with a resolving power E/ΔE > 700. The design of the OpSpec is presented. Photometric calculations based on expected opacity data are also presented. First use on NIF is expected in September 2016. [ABSTRACT FROM AUTHOR]

Single hit pulse height analysis is applied to National Ignition Facility x-ray framing cameras to quantify gain and gain variation in a single micro-channel plate-based instrument. This method allows the separation of gain from detectability in these photon-detecting devices. While pulse heights measured by standard-DC calibration methods follow the expected exponential distribution at the limit of a compound-Poisson process, gain-gated pulse heights follow a more complex distribution that may be approximated as a weighted sum of a few exponentials.We can reproduce this behavior with a simple statistical-sampling model. [ABSTRACT FROM AUTHOR]

The fusion diagnostic community, including the National Ignition Facility, the Laboratory for Laser Energetics, Megajoule in France, and others require optical recording instruments with precise time resolution covering a dynamic range of many orders of magnitude. In 2012, LLE, Photek, and Sydor Instruments embarked on the re-design of an improved streak tube for fusion diagnostics. As a baseline we started with the Photek ST-Y streak tube which is a member of the RCA design dating back to 1957, because the tube body can accommodate a 35 mm long photocathode, and consequently more fibre coupled diagnostic channels than smaller designs. Electron optical modelling was carried out by both Paul Jaanimagi in the US and by Photek with different software packages in a parallel exercise. Our goal was to address some of the short-comings of this tube, the initial approach being to increase the field between the photocathode and extractor electrode from 700 to 1300 V/mm to reduce space charge effects and to improve time resolution. Many changes and modifications were made: the time resolution was improved to 5 ps, the usable cathode length was increased from 20 mm to 32 mm under high extraction field operation, and the off-axis spatial resolution was substantially improved compared to other tubes of this format. Several tubes have been built and tested in Sydor ROSS-5800 streak cameras. [ABSTRACT FROM AUTHOR]

We describe the design and operation of a modified commercial rheometer to simultaneously perform rheological measurements and structural studies by small angle neutron scattering (SANS). The apparatus uses a Couette geometry shear cell allowing two of the three scattering planes to be observed by performing experiments in either the radial or tangential geometries. The device enables small angle neutron scattering patterns to be obtained simultaneously with a wide variety of rheological measurements such as stress/strain flow curves, oscillatory deformations, and creep, recovery and relaxation tests, from -20 °C to 150 °C, for samples with viscosities varying by several orders of magnitude. We give a brief report of recent experiments performed on a dispersion of acicular nanoparticles and biopolymer network under stress demonstrating the utility of such measurements. This device has been developed at the National Institute of Standards and Technology's Center for Neutron Research (NCNR) and made available to the complex fluids community as part of the standard sample environment equipment. [ABSTRACT FROM AUTHOR]

Quantum cascade lasers have ushered in a new era of enhanced capability for chemical sensing. The higher current and voltage demands of these devices over their laser diode counterparts have also ushered in the demand for more capable drive electronics. The current-sensitivity and high frequency response of these devices have continued the desire for low noise, stability, and agility enjoyed by the laser diode community for many years. This article addresses the issue of maintaining these characteristics at the currents and voltages required, and presents example performance of current controllers developed by the author at Pacific Northwest National Laboratory, achieving output currents up to 2 A and compliance voltages of 15 V, with noise levels close to the Johnson noise of the internal resistors, typically a few [formula]. Rapid full-depth current modulation up to 100 kHz is also demonstrated. [ABSTRACT FROM AUTHOR]

The extreme physics of targets shocked by NIF's 192-beam laser is observed by a diverse suite of diagnostics. Many diagnostics are being developed by collaborators at other sites, but ad hoc controls could lead to unreliable and costly operations. A diagnostic control system (DCS) framework for both hardware and software facilitates development and eases integration. Each complex diagnostic typically uses an ensemble of electronic instruments attached to sensors, digitizers, cameras, and other devices. In the DCS architecture each instrument is interfaced to a low-cost WINDOWS XP processor and JAVA application. Each instrument is aggregated with others as needed in the supervisory system to form an integrated diagnostic. The JAVA framework provides data management, control services, and operator graphical user interface generation. DCS instruments are reusable by replication with reconfiguration for specific diagnostics in extensible markup language. Advantages include minimal application code, easy testing, and high reliability. Collaborators save costs by assembling diagnostics with existing DCS instruments. This talk discusses target diagnostic instrumentation used on NIF and presents the DCS architecture and framework. [ABSTRACT FROM AUTHOR]

The first 3 of 18 neutron time-of-flight (nTOF) channels have been installed at the National Ignition Facility (NIF). The role of these detectors includes yield, temperature, and bang time measurements. This article focuses on nTOF data analysis and quality of results obtained for the first set of experiments to use all 192 NIF beams. Targets produced up to 2×1010 2.45 MeV neutrons for initial testing of the nTOF detectors. Differences in neutron scattering at the OMEGA laser facility where the detectors were calibrated and at NIF result in different response functions at the two facilities. Monte Carlo modeling shows this difference. The nTOF performance on these early experiments indicates that the nTOF system with its full complement of detectors should perform well in future measurements of yield, temperature, and bang time. [ABSTRACT FROM AUTHOR]

Absolute bang time measurements with the gas Cherenkov detector (GCD) and gamma reaction history (GRH) diagnostic have been performed to high precision at the OMEGA laser facility at the University of Rochester with bang time values for the two diagnostics agreeing to within 5 ps on average. X-ray timing measurements of laser-target coupling were used to calibrate a facility-generated laser timing fiducial with rms spreads in the measured coupling times of 9 ps for both GCD and GRH. Increased fusion yields at the National Ignition Facility (NIF) will allow for improved measurement precision with the GRH easily exceeding NIF system design requirements. [ABSTRACT FROM AUTHOR]

Backscattered light via laser-plasma instabilities has been measured in early NIF hohlraum experiments on two beam quads using a suite of detectors. A full aperture backscatter system and near backscatter imager (NBI) instrument separately measure the stimulated Brillouin and stimulated Raman scattered light. Both instruments work in conjunction to determine the total backscattered power to an accuracy of ∼15%. In order to achieve the power accuracy we have added time-resolution to the NBI for the first time. This capability provides a temporally resolved spatial image of the backscatter which can be viewed as a movie. [ABSTRACT FROM AUTHOR]

The first 96 and 192 beam vacuum Hohlraum target experiments have been fielded at the National Ignition Facility demonstrating radiation temperatures up to 340 eV and fluxes of 20 TW/sr as viewed by DANTE representing an ∼20 times flux increase over NOVA/Omega scale Hohlraums. The vacuum Hohlraums were irradiated with 2 ns square laser pulses with energies between 150 and 635 kJ. They produced nearly Planckian spectra with about 30±10% more flux than predicted by the preshot radiation hydrodynamic simulations. To validate these results, careful verification of all component calibrations, cable deconvolution, and software analysis routines has been conducted. In addition, a half Hohlraum experiment was conducted using a single 2 ns long axial quad with an irradiance of ∼2×1015 W/cm2 for comparison with NIF Early Light experiments completed in 2004. We have also completed a conversion efficiency test using a 128-beam nearly uniformly illuminated gold sphere with intensities kept low (at 1×1014 W/cm2 over 5 ns) to avoid sensitivity to modeling uncertainties for nonlocal heat conduction and nonlinear absorption mechanisms, to compare with similar intensity, 3 ns OMEGA sphere results. The 2004 and 2009 NIF half-Hohlraums agreed to 10% in flux, but more importantly, the 2006 OMEGA Au Sphere, the 2009 NIF Au sphere, and the calculated Au conversion efficiency agree to ±5% in flux, which is estimated to be the absolute calibration accuracy of the DANTEs. Hence we conclude that the 30±10% higher than expected radiation fluxes from the 96 and 192 beam vacuum Hohlraums are attributable to differences in physics of the larger Hohlraums. [ABSTRACT FROM AUTHOR]

The National Ignition Facility (NIF) successfully completed its first inertial confinement fusion (ICF) campaign in 2009. A neutron time-of-flight (nTOF) system was part of the nuclear diagnostics used in this campaign. The nTOF technique has been used for decades on ICF facilities to infer the ion temperature of hot deuterium (D2) and deuterium-tritium (DT) plasmas based on the temporal Doppler broadening of the primary neutron peak. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the yield with high accuracy. The NIF nTOF system is designed to measure neutron yield and ion temperature over 11 orders of magnitude (from 108 to 1019), neutron bang time in DT implosions between 1012 and 1016, and to infer areal density for DT yields above 1012. During the 2009 campaign, the three most sensitive neutron time-of-flight detectors were installed and used to measure the primary neutron yield and ion temperature from 25 high-convergence implosions using D2 fuel. The OMEGA yield calibration of these detectors was successfully transferred to the NIF. [ABSTRACT FROM AUTHOR]

We present the design and operation of a test cassette for exposure of samples to radiation environments at the National Ignition Facility. The cassette provides options for square and round samples and exposure areas; the cassette provides for multiple levels of filtration on a single sample, which allows dynamic range in experiments. The samples had normal lines of sight to the x-ray source in order to have uniform x-ray illumination. The incident x-radiation onto the samples was determined by the choice of filter thicknesses and materials. The samples were held at precise locations, accurate to within a few hundred microns, in the target chamber in order to have a known fluence incident. In the cassette, the samples were held in place in such a way that a minimal “line contact” allows them to have the maximal mechanical response to the x-ray load. We present postshot images of the debris found on films used for filters, and pre- and postexposure specimens. [ABSTRACT FROM AUTHOR]

The National Ignition Facility (NIF) is scheduled to begin deuterium-tritium (DT) shots possibly in the next several years. One of the important diagnostics in understanding capsule behavior and to guide changes in Hohlraum illumination, capsule design, and geometry will be neutron imaging of both the primary 14 MeV neutrons and the lower-energy downscattered neutrons in the 6–13 MeV range. The neutron imaging system (NIS) described here, which we are currently building for use on NIF, uses a precisely aligned set of apertures near the target to form the neutron images on a segmented scintillator. The images are recorded on a gated, intensified charge coupled device. Although the aperture set may be as close as 20 cm to the target, the imaging camera system will be located at a distance of 28 m from the target. At 28 m the camera system is outside the NIF building. Because of the distance and shielding, the imager will be able to obtain images with little background noise. The imager will be capable of imaging downscattered neutrons from failed capsules with yields Yn>1014 neutrons. The shielding will also permit the NIS to function at neutron yields >1018, which is in contrast to most other diagnostics that may not work at high neutron yields. The following describes the current NIF NIS design and compares the predicted performance with the NIF specifications that must be satisfied to generate images that can be interpreted to understand results of a particular shot. The current design, including the aperture, scintillator, camera system, and reconstruction methods, is briefly described. System modeling of the existing Omega NIS and comparison with the Omega data that guided the NIF design based on our Omega results is described. We will show NIS model calculations of the expected NIF images based on component evaluations at Omega. We will also compare the calculated NIF input images with those unfolded from the NIS images generated from our NIS numerical modeling code. [ABSTRACT FROM AUTHOR]

We present a new instrument, Hoxotope, for the in situ measurement of H2O and its heavy deuterium isotopologue (HDO) in the upper troposphere and lower stratosphere aboard the NASA WB-57. Sensitive measurements of δD are accomplished through the vacuum UV photolysis of water followed by laser-induced fluorescence detection of the resultant OH and OD photofragments. The photolysis laser-induced fluorescence technique can obtain S/N>20 for 1 ppbv HDO and S/N>30 for 5 ppmv H2O for 10 s data, providing the sensitivity required for δD measurements in the tropopause region. The technique responds rapidly to changing water concentrations due to its inherently small sampling volume, augmented by steps taken to minimize water uptake on instrument plumbing. Data from the summer 2005 Aura Validation Experiment Water Isotope Intercomparison Flights (AVE-WIIF) out of Houston, TX show agreement for H2O between Hoxotope and the Harvard water vapor instrument and for HDO between Hoxotope and the Harvard ICOS water isotope instrument, to within stated instrument uncertainties. The successful intercomparison validates Hoxotope as a credible source of δD data in the upper troposphere and lower stratosphere. [ABSTRACT FROM AUTHOR]

Features several scientific instruments in the United States. Charge-coupled device camera from PixelVision Inc.; Cylindrical lenses from Newport Corp.; Mother Node Platinum converter from Dwyer Instruments Inc.

Presents an abstract for a paper describing the preliminary operational plan and physics program for the International Thermonuclear Experimental Reactor (ITER) in La Jolla, California, and its implications for plasma measurements. Key objectives of the first ten years of ITER.

Presents an abstract of a paper reporting on the first plasma experiments with the 100 TW laser at the Lawrence Livermore National Laboratory in Livermore, California. Interaction of laser pulses with multilayer solid targets; Diagnostics; Range of electron densities; Energy conversion to the fast ions.

Presents an abstract of a paper reporting on tests of a high-sensitivity, high bandwidth, two-color interferometer on the Hawk pulsed power generator at the Naval Research Laboratory in Washington, D.C. Phase resolution; Use of the two-color feature to distinguish phase shifts from free electrons and bound electrons; Vibration isolation.

Describes a visible framing camera built to observe early time visible emission from z-pinch plasmas at the Saturn pulsed-power driven accelerator at Sandia National Laboratories in Albuquerque, New Mexico. Camera system; Optical system; Variation in sensitivity and gain characteristics from camera to camera.

Describes a modular filter developed at Argonne National Laboratory in Argonne, Illinois, that is intended for use in the undulator/wiggler beamlines at the Advanced Photon Source. Conceptual design; Actuator; Controls.

Development of analysis techniques for neutron imaging at the National Ignition Facility is an important and difficult task for the detailed understanding of high-neutron yield inertial confinement fusion implosions. Once developed, these methods must provide accurate images of the hot and cold fuels so that information about the implosion, such as symmetry and areal density, can be extracted. One method under development involves the numerical inversion of the pinhole image using knowledge of neutron transport through the pinhole aperture from Monte Carlo simulations. In this article we present results of source reconstructions based on simulated images that test the methods effectiveness with regard to pinhole misalignment. [ABSTRACT FROM AUTHOR]

Brookhaven National Laboratory has developed the new preinjector system, electron beam ion source (EBIS) for relativistic heavy ion collider (RHIC) and National Aeronautics and Space Administration Space Radiation Laboratory. Design of primary ion provider is an essential problem since it is required to supply beams with different ion species to multiple users simultaneously. The laser ion source with a defocused laser can provide a low charge state and low emittance ion beam, and is a candidate for the primary ion source for RHIC-EBIS. We show a suitable design with appropriate drift length and solenoid, which helps to keep sufficient total charge number with longer pulse length. The whole design of primary ion source, as well as optics arrangement, solid targets configuration and heating about target, is presented. [ABSTRACT FROM AUTHOR]

We present K-α x-ray Thomson scattering from shock compressed matter for use as a diagnostic in determining the temperature, density, and ionization state with picosecond resolution. The development of this source as a diagnostic as well as stringent requirements for successful K-α x-ray Thomson scattering are addressed. Here, the first elastic and inelastic scattering measurements on a medium size laser facility have been observed. We present scattering data from solid density carbon plasmas with >1×105 photons in the elastic peak that validate the capability of single shot characterization of warm dense matter and the ability to use this scattering source at future free electron lasers and for fusion experiments at the National Ignition Facility (NIF), LLNL. [ABSTRACT FROM AUTHOR]

We have successfully demonstrated a 7.5 ns duration pinhole-apertured backlighter at the Omega laser facility. Pinhole-apertured point-projection backlighting for 8 ns will be useful for imaging evolving features in experiments at the National Ignition Facility. The backlighter consisted of a 20 μm diameter pinhole in a 75 μm thick Ta substrate separated from a Zn emitter (9 keV) by a 400 μm thick high-density carbon piece. The carbon prevented the shock from the laser-driven surface from reaching the substrate before 8 ns and helped minimize x-ray ablation of the pinhole substrate. Grid wires in x-ray framing camera images of a gold grid have a source-limited resolution significantly smaller than the pinhole diameter due to the high aspect ratio of the pinhole, but do not become much smaller at late times. [ABSTRACT FROM AUTHOR]

Describes the design of the electron cyclotron resonance ion source for the production of medium charge states ions in Berkeley, California. Features of the ion source; Enhancement of the ion confinement time by enlarging the source plasma volume; Production of the axial magnetic mirror field by water-cooled copper pancake coils.

Discusses the time-resolved x-ray scattering program at the Advanced Photon Source in Argonne, Illinois. Focusing and wide bandpass optics; Detectors; Examples of time-resolved techniques being developed at the facility.

Evaluates the performance of position monitors implemented in three undulator beamlines at the Advanced Light Source synchrotron radiation source in Berkeley, California. Monitor design; Calibration; Planned improvements.

Describes a set of high heat load horizontal and vertical white-beam slits that was designed for the Advanced Photon Source wiggler/undulator beamlines at Argonne National Laboratory in Argonne, Illinois. Design specifications; Grazing-incidence knife-edge configuration; Parallelogram driving structure for vertical slits; Horizontal slits.

Describes the undulator based beamline X13A at the National Synchrotron Light Source in Upton, New York. Criteria for the beamline design; Undulator magnetic gap; X13 miniundulator; Photon flux measurements.

Describes a set of precision horizontal and vertical white-beam slits designed for the Advanced Photon Source (APS) x-ray undulator beamlines at Argonne National Laboratory in Argonne, Illinois. Major design challenges for the APS white-beam slit for undulator beamlines; Design specifications; Main components of the L5 white-beam slit assembly.

Discusses the reconfiguration of the X-23B hard x-ray beamline of the Naval Research Laboratory in Washington, D.C., in an effort to increase the beamline's flux and energy range. Beamline design features; Optical design; Mechanical design; Calculated geometrical transmission factor of the optics for all rays.

Discusses the x-ray optics and performance of the Argonne National Laboratory X6B beamline at the National Synchrotron Light Source in Argonne, Illinois. Optics description and beamline operation; Surface diffraction; X-ray absorption fine structure.

Describes two multipurpose optical tables and a six-circle goniometer support system designed for optics in the experiment stations of the Advanced Photon Source at Argonne National Laboratory in Argonne, Illinois. Specifications; Mechanical designs.

Describes a variable groove-spaced grating monochromator for soft x-ray emission that was commissioned at the Center for Advanced Microstructures and Devices at Louisiana State University in Baton Rouge, Louisiana. Optical design; TNT beamline; Photon flux; Resolution.

Indicates the results of line brightness temperature calculations for parameters at the International Thermonuclear Experimental Reactor (ITER). Explanation of results on the Tokamak Fusion Test Reactor (TFTR); Feasibility of time-resolved measurements of the central ion temperature and central plasma parameters on ITER; Presence of high fluxes of neutrons.

The Radiochemical Analysis of Gaseous Samples (RAGS) diagnostic apparatus was recently installed at the National Ignition Facility (NIF). Following a NIF shot, RAGS is used to pump the gas load from the NIF chamber for purification and isolation of the noble gases. After collection, the activated gaseous species are counted via gamma spectroscopy for measurement of the capsule areal density and fuel-ablator mix. Collection efficiency was determined by injecting a known amount of 135Xe into the NIF chamber, which was then collected with RAGS. Commissioning was performed with an exploding pusher capsule filled with isotopically enriched 124Xe and 126Xe added to the DT gas fill. Activated xenon species were recovered post-shot and counted via gamma spectroscopy. Results from the collection and commissioning tests are presented. The performance of RAGS allows us to establish a noble gas collection method for measurement of noble gas species produced via neutron and charged particle reactions in a NIF capsule. [ABSTRACT FROM AUTHOR]

A chemical vapor deposition polycrystalline photoconductive diamond detector was fielded at NIF to measure the time of peak x-ray emission, or x-ray bang time, of inertial confinement fusion implosions. Imaging the capsule with a pinhole provides contrast against Hohlraum emission, allowing clear identification of the capsule component in the raw scope trace. X-ray bang time was measured to within ±41-46 ps with the internal photoconductive diamond detector. [ABSTRACT FROM AUTHOR]

Accurately assessing and optimizing the implosion performance of inertial confinement fusion capsules is a crucial step to achieving ignition on the NIF. We have applied differential filtering (matched Ross filter pairs) to provide broadband time-integrated absolute x-ray self-emission images of the imploded core of cryogenic layered implosions. This diagnostic measures the temperature- and density-sensitive bremsstrahlung emission and provides estimates of hot spot mass, mix mass, and pressure. [ABSTRACT FROM AUTHOR]