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The National Ignition Facility (NIF) diagnostic instrument manipulator (DIM) - based high resolution (dHIRES) x-ray spectrometer was used to measure the time evolution of the electron density (n e) and temperature (T e) in the hot spot of four NIF compressed capsules with 25 ps time resolution during the ‘stagnation’ phase. The electron density was inferred by comparing the measured Stark broadening of the krypton (Kr) Heβ spectral complex with theoretical calculations that include ion dynamic effects, and the electron temperature was inferred by comparing the measured ratio of the intensity of a dielectronically excited Li-like Kr line to the intensity of the Kr Heβ resonance line with calculations using the spectroscopic collisional radiative atomic model (SCRAM) and CRETIN collisional-radiative models. The inferred, time averaged n e values mainly agree with n e values from neutron diagnostics within uncertainties, but the neutron time-of-flight values of T ion are consistently higher than dHIRES T e values by 200–700 eV. The dHIRES measurements and measurement techniques, method of uncertainty analysis, and discussion of comparisons with measurements from neutron diagnostics are presented.

The use of x-ray diffraction (XRD) measurements in laser-driven dynamic compression experiments at high-power laser facilities is becoming increasingly common. Diffraction allows one to probe in situ the transformations occurring at the atomic level at extreme conditions of pressure, temperature, and time scale. In these measurements, the x-ray source is generated by irradiation of a solid foil. Under certain laser drive conditions, quasimonochromatic He-α radiation is generated. Careful analysis of the x-ray source plasma spectra reveals that this radiation is not a single line emission and that monochromaticity is highly dependent on the laser irradiance. In this work, we analyze how the spectra emitted by laser-irradiated copper, germanium, and iron foils at the Omega Laser vary depending on different laser drive conditions and discuss the implications for XRD experiments.

We report the development of a high-resolution spectrometer for extended x-ray absorption fine structure (EXAFS) studies of materials under extreme conditions. A curved crystal and detector in the spectrometer are replaceable such that a single body is employed to perform EXAFS measurements at different x-ray energy intervals of interest. Two configurations have been implemented using toroidal crystals with Ge 311 reflection set to provide EXAFS at the Cu K-edge (energy range 8.9-9.8 keV) and Ge 400 reflection set to provide EXAFS at the Ta L3-edge (9.8-10.7 keV). Key performance characteristics of the spectrometer were found to be consistent with design parameters. The data generated at the National Ignition Facility have shown an ≃3 eV spectral resolution for the Cu K-edge configuration and ≃6 eV for the Ta L3-edge configuration.

This paper describes a new class of focusing crystal forms for the x-ray Bragg crystal spectroscopy of small, point-like, x-ray sources. These new crystal forms are designed with the aid of sinusoidal spirals, a family of curves, whose shapes are defined by only one parameter, which can assume any real value. The potential of the sinusoidal spirals for the design x-ray crystal spectrometers is demonstrated with the design of a toroidally bent crystal of varying major and minor radii for measurements of the extended x-ray absorption fine structure near the Ta-L3 absorption edge at the National Ignition Facility.

We study continuum x-ray emission from hot plasma at the National Ignition Facility (NIF). We find that the x-ray yield in the multi-keV photon energy range is larger in Ti than in Ag or Au. This apparent paradox is due to Ti K-shell vacancies generated by the extraordinary energy density achieved by the NIF lasers. This is supported by direct observations of large continuum enhancement above the Ti K-series limit due to both free–bound (recombination) emission and strong Lyα (H-like) emission. Detailed calculations agree well with our measurements and support our conclusions.

Fuel areal density (ρR) of all recent indirectly driven, cryogenically-layered DT implosions at the National Ignition Facility (NIF) show a deficit when compared to simulations. Across all designs, experimental ρR is lower than in 1D simulations without alpha energy or momentum deposition. A series of layered implosions were fielded at NIF to assess the impact of fuel-ablator instability, as caused by M-band preheat, on lower-than-expected fuel areal density. The stability of the fuel-ablator interface is modified by varying the Atwood number through a series of experiments where capsules were fielded with different ablator dopant levels. A key finding of this campaign is that optimization of 1D physics (shock timing) dominates stabilization of the fuel-ablator interface.

We have performed refraction enhanced radiography (RER) measurements of indirect drive layered high density carbon capsule implosions relevant for inertial confinement fusion. Streaked RER data using a 5 µm wide imaging slit, backlit by a 7.8 keV Ni He-α laser driven x-ray source, shows features due to inflight density gradients in the ablator and fuel ice that are not visible in absorption only radiographs. To avoid motional blurring at smaller in-flight radii, we concentrate our probe to the main compression and N+1 shock phases. During the main compression phase, both simulations and data show fringes consistent with steep density gradients. During the later N+1 shock phase we see loss of fringes and hence infer less fuel compression than simulated, that may be caused by ice-ablator mix. Quantitative analysis shows that at the ablation front during the main compression phase, the simulated density differential agrees with the data, but the inferred scale length is 50% longer than simulated. During the N+1 shock phase, the data shows 2x higher ablation front density than simulated for similar scale lengths that may be affected by data cross talk with the reduced fuel compression at the ice-ablator interface.

In the quest for reaching ignition of deuterium-tritium (DT) fuel capsule implosions, experiments on the National Ignition Facility (NIF) have shown lower final fuel areal densities than simulated. Possible explanations for reduced compression are higher preheat that can increase the ablator-DT ice density jump and induce mix at that interface or reverberating shocks. We are hence developing x-ray Refraction Enhanced Radiography (RER) to infer the inflight density profiles in layered fuel capsule implosions. We use a 5 μm slit backlit by a Ni 7.8 keV He-α NIF laser driven x-ray source positioned at 20 mm from the capsule to cast refracted images of the inflight capsule onto a streak camera in a high magnification (M ∼ 60×) setup. Our first experiments have validated our setup that recorded a streaked x-ray fringe pattern from an undriven high density carbon (HDC) capsule consistent with ray tracing calculations at the required ∼6 μm and 25 ps resolution. Streaked RER was then applied to inflight layered HDC capsule implosions using a hydrogen-tritium fuel mix rather than DT to reduce neutron yields and associated backgrounds. The first RER of an imploding capsule revealed strong features associated with the ablation front and ice-ablator interface that are not visible in standard absorption radiographs.In the quest for reaching ignition of deuterium-tritium (DT) fuel capsule implosions, experiments on the National Ignition Facility (NIF) have shown lower final fuel areal densities than simulated. Possible explanations for reduced compression are higher preheat that can increase the ablator-DT ice density jump and induce mix at that interface or reverberating shocks. We are hence developing x-ray Refraction Enhanced Radiography (RER) to infer the inflight density profiles in layered fuel capsule implosions. We use a 5 μm slit backlit by a Ni 7.8 keV He-α NIF laser driven x-ray source positioned at 20 mm from the capsule to cast refracted images of the inflight capsule onto a streak camera in a high magnification (M ∼ 60×) setup. Our first experiments have validated our setup that recorded a streaked x-ray fringe pattern from an undriven high density carbon (HDC) capsule consistent with ray tracing calculations at the required ∼6 μm and 25 ps resolution. Streaked RER was then applied to inflight layered H...

Extended X-ray absorption fine structure (EXAFS) spectroscopy is a powerful tool for in situ characterization of matter in the high energy density regime. An EXAFS platform is currently being developed on the National Ignition Facility. Development of a suitable X-ray backlighter involves minimizing the temporal duration and source size while maximizing spectral smoothness and brightness. One approach involves imploding a spherical shell, which generates a high-flux X-ray flash at stagnation. We present results from a series of experiments comparing the X-ray source properties produced by imploded empty and Ar-filled capsules.

The here-described spectrometer was developed for the extended x-ray absorption fine structure spectroscopy of high-density plasmas at the National Ignition Facility. It employs as the Bragg reflecting element a new type of toroidally bent crystal with a constant and very large major radius R and a much smaller, locally varying, minor radius r. The focusing properties of this crystal and the experimental arrangement of the source and detector make it possible to (a) fulfill the conditions for a perfect imaging of an ideal point source for each wavelength, (b) obtain a high photon throughput, (c) obtain a high spectral resolution by eliminating the effects of source-size broadening, and (d) obtain a one-dimensional spatial resolution with a high magnification perpendicular to the main dispersion plane.

We report on the first multilocation electron temperature (T_{e}) and flow measurements in an ignition hohlraum at the National Ignition Facility using the novel technique of mid-Z spectroscopic tracer "dots." The measurements define a low resolution "map" of hohlraum plasma conditions and provide a basis for the first multilocation tests of particle and energy transport physics in a laser-driven x-ray cavity. The data set is consistent with classical heat flow near the capsule but reduced heat flow near the laser entrance hole. We evaluate the role of kinetic effects, self-generated magnetic fields, and instabilities in causing spatially dependent heat transport in the hohlraum.

In inertial confinement fusion (ICF) experiments on the National Ignition Facility (NIF), measurements of average ion temperature using DT neutron time of flight broadening and of DD neutrons do not show the same apparent temperature. Some of this may be due to time and space dependent temperature profiles in the imploding capsule which are not taken into account in the analysis. As such, we are attempting to measure the electron temperature by recording the free-free electron-ion scattering-spectrum from the tail of the Maxwellian temperature distribution. This will be accomplished with the new NIF Continuum Spectrometer (ConSpec) which spans the x-ray range of 20 keV to 30 keV (where any opacity corrections from the remaining mass of the ablator shell are negligible) and will be sensitive to temperatures between ∼ 3 keV and 6 keV. The optical design of the ConSpec is designed to be adaptable to an x-ray streak camera to record time resolved free-free electron continuum spectra for direct measurement of the dT/dt evolution across the burn width of a DT plasma. The spectrometer is a conically bent Bragg crystal in a focusing geometry that allows for the dispersion plane to be perpendicular to the spectrometer axis. Additionally, to address the spatial temperature dependence, both time integrated and time resolved pinhole and penumbral imaging will be provided along the same polar angle. The optical and mechanical design of the instrument is presented along with estimates for the dispersion, solid angle, photometric sensitivity, and performance.

X-ray penumbral imaging has been successfully fielded on a variety of inertial confinement fusion (ICF) capsule implosion experiments on the National Ignition Facility (NIF). We have demonstrated sub-5 μm resolution imaging of stagnated plasma cores (hot spots) at x-ray energies from 6 to 30 keV. These measurements are crucial for improving our understanding of the hot deuterium-tritium fuel assembly, which can be affected by various mechanisms, including complex 3-D perturbations caused by the support tent, fill tube or capsule surface roughness. Here we present the progress on several approaches to improve x-ray penumbral imaging experiments on the NIF. We will discuss experimental setups that include penumbral imaging from multiple lines-of-sight, target mounted penumbral apertures and variably filtered penumbral images. Such setups will improve the signal-to-noise ratio and the spatial imaging resolution, with the goal of enabling spatially resolved measurements of the hot spot electron temperature and material mix in ICF implosions.

Pushered Single Shells (PSSs) are an alternative approach to Inertial Confinement Fusion implosions that employ high-Z materials in the innermost capsule layer (pusher) as a means to enhance radiation trapping and lower core ignition requirements. However, adding high-Z materials can also increase losses due to mix, provide extra tamping, and make the capsule emission opaque to x-ray diagnostics. The first PSS implosions performed on the National Ignition Facility use plastic ablators with a germanium (Ge) dopant as a high-Z surrogate in the pusher to isolate the effects of high-Z mix and radiation trapping without changing tamping. Using a 2-shock laser pulse, the PSS implosions are designed and symmetrized to reach 3.7 keV core temperatures. A low concentration (2.8%) Ge dopant is added to the innermost layer, and the resulting effects on mix and x-ray opacity are observed. The method of separated reactants is used to infer information about mixing between the deuterated plastic pusher and the capsule fill gas (25% tritium) from the resulting nuclear DT reactions. Radiation transport is studied via capsule emission x-ray spectroscopy and imaging. Both nuclear and x-ray data corroborate the hypothesis that the addition of Ge strongly affects the mix region through radiation losses but has a minimal effect on the core and the warm, unmixed regions. Simulations using diffusive and turbulent mix models agree qualitatively with data, but quantitative agreement may require hybrid mix models that can model the transitional regime between turbulence and diffusion. Simulations matching the observables show increased core radiation trapping when Ge is added.

We report on the performance of high x-ray fluence Kr K-shell sources that are being developed for high energy density experiments. These targets are 4.1 mm in diameter 4.4 mm tall hollow epoxy tubes having a 40 μm thick wall holding 1.5 atm of Kr gas. For these shots, the National Ignition Facility laser delivered a nominally constant total energy of ≈750 kJ of 351 nm (3ω) light at the three power levels [e.g., ≈120 (low), ≈145 (medium), and ≈210 TW (high)]. The Kr K-shell (Ephoton = 8–20 keV) x-ray radiant intensity and radiant energy (kJ/sr) of these sources were found to increase as a function of laser power but began to plateau at the highest laser power. The Kr K-shell radiant energy increased from ≈1 kJ/sr at ≈120 TW to ≈2 kJ/sr at ≈210 TW. Radiation hydrodynamics simulations predict radiant energies to be always higher than these measurements. The increase in K-shell emission is attributed to its strong dependence on the electron temperature. Electron temperature distributions were inferred from measured Heα and Lyα line emission through the use of a genetic algorithm and Scram modeling. The inferred temperatures from the experiment are 20% to 30% higher than those predicted from modeling.

The sensitivity of Fuji SR and MS image plates (IPs) used in x-ray spectrometers on OMEGA and the National Ignition Facility has been measured using two techniques. A set of radioisotopes has been used to constrain image-plate sensitivity between 6 and 60 keV, while a Manson source has been used to expose image plates to x rays at energies between 1.5 and 8 keV. These data have shown variation in sensitivity on the order of 5% for a given IP type and scanner settings. The radioisotope technique has also been used to assess IP fading properties for MS-type plates over long times. IP sensitivity as a function of scanner settings and pixel size has been systematically examined, showing variations of up to a factor of 2 depending on the IP type. Cross-calibration of IP scanners at different facilities is necessary to produce a consistent absolute sensitivity curve spanning the energy range of 2-60 keV.

X-ray spectroscopy has been newly used to diagnose electron temperatures in planar-geometry experiments at the National Ignition Facility (NIF) designed to study laser-plasma interactions at plasma conditions relevant to direct-drive ignition. These experiments used a buried co-mixed Mn/Co microstrip in a CH ablator in experiments that generated long scale-length plasmas susceptible to stimulated Raman scattering (SRS). Time-resolved Mn and Co K-shell spectra, diagnosed using the NIF x-ray spectrometer, were analyzed by fitting to synthetic spectra based on a detailed atomic model of emission from the microstrip. The electron temperature at the time when the microstrip passes through the quarter-critical density surface, the key region for the development of SRS, was inferred to be around 2–3 keV. These measurements constrain 2-D DRACO radiation-hydrodynamic modeling of the planar experiments, important for determining plasma conditions pertinent to SRS, and demonstrate that this platform approaches direct-drive ignition-relevant conditions. The modeling is also assessed by a direct comparison of measured spectra to modeled spectra generated by DRACO in conjunction with the atomic physics postprocessor code SPECT3D.

We present a technique for determining the X-ray spectral quality from each region of an elliptically curved PET(002) crystal. The investigative technique utilizes the shape of the crystal rocking curve which changes significantly as the radius of curvature changes. This unique quality information enables the spectroscopist to verify where in the spectral range that the spectrometer performance is satisfactory and where there are regions that would show spectral distortion. A collection of rocking curve measurements for elliptically curved PET(002) has been built up in our X-ray laboratory. The multi-lamellar model from the XOP software has been used as a guide and corrections were applied to the model based upon measurements. But, the measurement of RI at small radius of curvature shows an anomalous behavior; the multi-lamellar model fails to show this behavior. The effect of this anomalous RI behavior on an X-ray spectrometer calibration is calculated. It is compared to the multi-lamellar model calculation which is completely inadequate for predicting RI for this range of curvature and spectral energies.

A high resolution, Diagnostic Instrument Manipulator (DIM)-based x-ray Bragg crystal spectrometer has been calibrated for and deployed at the National Ignition Facility (NIF) to diagnose plasma conditions in ignition capsules near stagnation times. The spectrometer has two conical crystals in the Hall geometry focusing rays from the Kr Heα, Lyα, and Heβ complexes onto a streak camera, with the physics objectives of measuring time-resolved electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. A third von Hamos crystal that time-integrates the Kr Heα, Heβ and intervening energy range provides in situ calibration for the streak camera signals. The spectrometer has been absolutely calibrated using a microfocus x-ray source, an array of CCD and single-photon-counting detectors, and multiple K- and L-absorption edge filters at the Princeton Plasma Physics Laboratory (PPPL) x-ray laboratory. Measurements of the integrated reflectivity, energy range, and energy resolution for each crystal are discussed. These calibration data provide absolute x-ray signal levels for NIF measurements, enabling precise filter selection and comparisons to simulations.

At large laser faculties, such as OMEGA and the National Ignition Facility (NIF), x-ray spectrometers are provided by the facility to diagnose plasma conditions or monitor backlighters. Often the calibration of these spectrometers is unknown or out of date. As a remedy to this situation, we present a simple ray trace method to calibrate flat crystal spectrometers using only basic information regarding the optical design of the spectrometer. This model is then used to output photometric throughput estimates, dispersion, solid angle, and spectral resolution estimates. This model is applied to the mono angle crystal spectrometer and Super Snout I at the NIF and the X-Ray Spectrometer at the OMEGA laser facility.

At the National Ignition Facility (NIF), storage phosphor image plates (IP) are used extensively for recording x-rays, charged particles, and neutrons. For x-ray imaging and spectroscopy, absolute and relative calibrations are important for extracting plasma information from the diagnostics. We use Fuji MS, SR, and TR image plates that have been cut to fit custom diagnostic envelopes. The image plates are scanned on a General Electric FLA 7000 IP flying spot scanner. Calibrations for sensitivity, spatial scale, and temperature dependent fade are applied. During a set of recent calibrations, we noticed large shifts in the absolute calibration of the image plate system. The possible source of these shifts is discussed. We discuss scanner stability and a method for calibration. We discuss the fade and temperature effects of the image plates and how this correction is applied within the NIF environment. We also compare our NIF GE FLA 7000 IP scanner with a new General Electric Amersham Typhoon IP scanner.

We describe a 160×100 mm two-dimensional position-sensitive proportional counter for use in high-temperature plasma spectroscopy. The detector employs a novel design based on a printed circuit board for the cathode plane and a single-wire switchback design for the anode plane. The spacial resolution for one dimension is 200 μm and for the other dimension is 2–5 mm. The integral nonlinearity is 0.08% for the first and 1% for the second dimension. We demonstrate the utility of the new detector with a spacially resolved measurement of the Lyman-α transitions in hydrogenic Ar17+.

A high-resolution x-ray crystal spectrometer has recently been installed at the National Spherical Torus Experiment to record the satellite spectra of helium-like argon, Ar XVII, in the wavelength range from 3.94 to 4.00 A for measurements of ion and electron temperatures, and measurements of the ionization equilibrium of argon, which is of interest for studies of ion transport. The instrument presently consists of a spherically bent quartz crystal and a conventional one-dimensional position-sensitive multiwire proportional counter, but it will soon be upgraded to a new type of x-ray imaging crystal spectrometer by the installation of a large size (10 cm×30 cm) two-dimensional position-sensitive detector that will allow us to obtain temporally and spatially resolved spectra from a 80 cm high cross-section of the plasma. In its present configuration, the spectrometer has been optimized for high throughput so that it is possible to record spectra with small statistical errors with a time resolution of 10 ms...

Extended X-ray absorption Fine Structure (EXAFS) measurements require a bright, spectrally smooth, and broad-band x-ray source. In a laser facility, such an x-ray source can be generated by a laser-driven capsule implosion. In order to optimize the x-ray emission, different capsule types and laser irradiations have been tested at the National Ignition Facility (NIF). A crystal spectrometer is used to disperse the x-rays and high efficiency image plate detectors are used to measure the absorption spectra in transmission geometry. EXAFS measurements at the K-edge of iron at ambient conditions have been obtained for the first time on the NIF laser, and the requirements for optimization have been established.

High-resolution spectroscopy of the 2s(1/2)-2p(1/2) transition in the extreme ultraviolet region is shown to resolve the level splitting induced by the nuclear magnetic field of both the 2s(1/2) and the 2p(1/2) levels in lithiumlike (141)Pr(56+) and of the 2s(1/2)2p(1/2) (3)P(1) level in berylliumlike (141)Pr(55+). The (141)Pr ions are an ideal test of this measurement approach because their energy levels are known well from first principles and are unaffected by small energy contributions from QED and nuclear magnetization effects. The accuracy attained in the measured 196.5 ± 1.2 meV 2s(1/2) splitting is more than an order of magnitude better than that achieved before using crystal spectroscopy of the 2s(1/2)-2p(3/2) x-ray transition and at the level needed to implement a proposed scheme for disentangling the contributions from QED and nuclear magnetization effects in higher-Z ions, such as (209)Bi.

The photometric calibration of an extreme ultraviolet flat field spectrometer has been done at the Advanced Light Source at Lawrence Berkeley National Laboratory. This spectrometer is used to record spectrum for atomic physics research from highly charged ions in plasmas created in the Livermore electron beam ion traps EBIT-I and SuperEBIT. Two calibrations were done each with a different gold-coated grating, a 1200 l/mm and a 2400 l/mm, that covered 75–300 A and 15–160 A, respectively. The detector for this calibration was a back thinned charge coupled device. The relative calibration was determined for several different incident angles for both gratings. Within the scatter of the data, the calibration was roughly insensitive to the incidence angle for the range of angles investigated.

Single‐shot x‐ray spectra from electron bunches produced by a laser‐plasma wakefield accelerator (LPA) [1, 2] were measured using a photon‐counting single‐shot pixelated Silicon‐based detector [3], providing for the first time single‐shot direct spectra without assumptions required by filter based techniques. In addition, the electron bunch source size was measured by imaging a wire target, demonstrating few micron source size and stability. X‐rays are generated when trapped electrons oscillate in the focusing field of the wake trailing the driver laser pulse [4, 5, 6, 7, 8]. In addition to improving understanding of bunch emittance and wake structure, this provides a broadband, synchronized femtosecond source of keV x‐rays. Electron bunch spectra and divergence were measured simultaneously and preliminary analysis shows correlation between x‐ray and electron spectra. Bremsstrahlung background was managed using shielding and magnetic diversion.

International audience; We have used the EBIT Calorimeter Spectrometer (ECS), a microcalorimeter instrument built by the calorimeter group at the NASA/Goddard Space Flight Center, to make a variety of measurements since its installation at Lawrence Livermore National Laboratory's EBIT facility. These include measurements of charge exchange between neutral gas and K-and L-shell ions, measurements of the X-ray transmission efficiency of optical blocking filters, high resolution measurements of transition energies for high-Z, highly charged ions, and measurements of M and L-shell emission from highly charged tungsten following on earlier measurements of L-shell gold. Our results will see application in the interpretation of the spectra from the Jovian atmosphere and of the diffuse soft X-ray background, in tests of QED, and in diagnosing inertial and magnetic confinement fusion plasmas. These measurements augment previous laboratory astrophysics, atomic physics, and calibration measurements made using earlier versions of NASA's microcalorimeter spectrometer.

The Electron Beam Ion Trap (EBIT) facility at the Lawrence Livermore National Laboratory is being used to absolutely calibrate the transmission efficiency of x-ray filters employed by diodes and spectrometers used to diagnose laser-produced plasmas. EBIT emits strong, discrete monoenergetic lines at appropriately chosen x-ray energies. X rays are detected using the high resolution EBIT Calorimeter Spectrometer (ECS), developed for LLNL at the NASA/Goddard Space Flight Center. X-ray filter transmission efficiency is determined by dividing the x-ray counts detected when the filter is in the line of sight by those detected when out of the line of sight. Verification of filter thickness can be completed in only a few hours, and absolute efficiencies can be calibrated in a single day over a broad range from about 0.1 to 15 keV. The EBIT calibration lab has been used to field diagnostics (e.g., the OZSPEC instrument) with fully calibrated x-ray filters at the OMEGA laser. Extensions to use the capability for calibrating filter transmission for the DANTE instrument on the National Ignition Facility are discussed.

Measurements of the L -shell emission of highly charged gold ions were made under controlled laboratory conditions using the SuperEBIT electron beam ion trap, allowing detailed spectral observations of lines from Fe-like Au53+ through Ne-like Au69+ . Using atomic data from the Flexible Atomic Code, we have identified strong 3d_{52}-->2p_{32} emission features that can be used to diagnose the charge state distribution in high energy density plasmas, such as those found in the laser entrance hole of hot hohlraum radiation sources. We provide collisional-radiative calculations of the average ion charge Z as a function of temperature and density, which can be used to relate charge state distributions inferred from 3d_{52}-->2p_{32} emission features to plasma conditions, and investigate the effects of plasma density on calculated L -shell Au emission spectra.

Measurements of the L -shell emission of highly charged gold ions were made under controlled laboratory conditions using the SuperEBIT electron beam ion trap, allowing detailed spectral observations of lines from Fe-like Au53+ through Ne-like Au69+ . Using atomic data from the Flexible Atomic Code, we have identified strong 3d_{52}--2p_{32} emission features that can be used to diagnose the charge state distribution in high energy density plasmas, such as those found in the laser entrance hole of hot hohlraum radiation sources. We provide collisional-radiative calculations of the average ion charge Z as a function of temperature and density, which can be used to relate charge state distributions inferred from 3d_{52}--2p_{32} emission features to plasma conditions, and investigate the effects of plasma density on calculated L -shell Au emission spectra.

Measurements of hyperfine splittings in highly charged ions are sensitive to details of the nuclear structure and the nuclear magnetic field distribution, but the proper interpretation of the measurements requires that the atomic structure is understood in sufficient detail. We discuss the reasoning behind various recent experiments and what advantage is offered by the study of the Li-like ion of a mid-Z element such as praseodymium.

Summary form only given. The X-ray emission of high-temperature plasmas contains a wealth of information about the plasma conditions. One of the plasma parameters of interest is the electron temperature which can be determined from the distribution of the ionic species in the plasma. Each ion charge distribution emits a characteristic X-ray spectrum and, thus, high-resolution X-ray spectroscopy provides a tool to observe this characteristic "fingerprint". We present survey spectra from highly charged gold ions which have been measured at the Livermore SuperEBIT facility. These survey spectra show that measuring the L-shell emission of highly charged gold ions can be used for the determination of the electron temperature in high-temperature gold plasmas, such as laser-generated plasmas of gold hohlraums and halfraums, respectively

Summary form only given, as follows. A new X-ray imaging crystal spectrometer, which consists of a spherically bent. crystal and a large (10 cm /spl times/ 30 cm) 2D position-sensitive detector, is being installed at the National Spherical Torus Experiment (NSTX). This instrument will record temporally and spatially resolved spectra of helium-like argon from a large number of sightlines through the plasma to measure radial profiles and gradients of the electron temperature, ion temperature, plasma rotation velocity, and ionization equilibrium.

This paper summarizes the results of studies to enhance the performance of Dresden Electron Beam Ion Traps regarding aspects which are important for charge breeding, i.e. the injection of externally produced low charged ions and their conversion to highly charged ions. The properties of the electron beam of this compact room-temperature operated EBIT were investigated via position sensitive X-ray detection. A detailed analysis of the spatial distribution as well as the energy of the X-ray photons emitted from the electron beam region allowed for the determination of the source parameters needed to guarantee optimal ion trapping conditions and ionization rates. The parameters found in this investigation were applied for the successful realization of charge breeding with the Dresden EBIT.

We present a measurement of the cross section for electron-impact excitation of Lyman-α1 in hydrogen-like iron (Z = 26) and nickel (Z = 28) over a broad range of energies using the Lawrence Livermore National Laboratory SuperEBIT electron beam ion trap facility. The measurement was performed with electron beam energies between 35 keV and 85 keV. The hydrogen-like spectrum of iron and nickel was observed, and fully resolved, with the XRS/EBIT x-ray microcalorimeter spectrometer, which allowed for an absolute cross section to be measured by normalizing to the RR x-ray emission. These results are compared to theory.

We report the measurement of the Kβ2/Kβ 1 ratio of He-like krypton using the SuperEBIT electron beam ion trap at the Lawrence Livermore National Laboratory. The energy of these lines are about 15 keV, which is twice as high as the energy of such lines measured before. A comparison with theoretical predictions shows poor agreement, confirming the trend uncovered earlier where the measured result is considerably larger than predicted.

The Electron Beam Ion Trap Microcalorimeter Spectrometer (ECS) routinely surveys the K-shell x-ray spectra that fall into the energy range between 200 eV and 14,000 eV. The spectra serve as in situ energy references and include the K-shell emission from ions between boron at the low-energy end and krypton at the high end. Example spectra are presented of the n = 2 → n = 1 emission from heliumlike noble gas ions neon, argon, and krypton, from the heliumlike transition metals iron and nickel, as well as the heliumlike ions of boron, silicon, sulfur, and germanium.

We have designed and implemented a laser ablation system to inject neutral material into the EBIT-I and SuperEBIT high-energy electron beam ion trap at the Lawrence Livermore National Laboratory. A laser-generated vapor created from a solid material target was scrubbed of ions prior to injection into the trap in the form of a collimated beam. We used a Q-switched Nd:YAG laser with a pulse duration of 15.7ns full width at half maximum and intensities at the target controllable from 0.035to0.46GW∕cm2. Compared with other injection methods, this pulsed system adds new flexibility including the ability to vary fill trap in both time and quantity and without changing trap or beam parameters. Moreover, it allows us to inject materials that are not readily injected by the standard metal vapor vacuum arc (MeVVA) method. Performance comparisons between the laser ablation system and MeVVA method are presented.

Cost effectiveness and clinical applicability of 2-liter flexible polyvinyl chloride containers for administration of total parenteral nutrient (TPN) solutions were studied. Times were measured for single and batch compounding of 50 2-liter and 50 1-liter TPN solutions and for nursing time associated with administration of 20 1-liter and 20 2-liter TPN solutions. Costs were calculated for personnel time and supplies for 100 1-liter and 50 2-liter TPN solutions using single and batch compounding. Rates of return, reuse, and waste were compared during a two-month period. Questionnaires were administered to nurses and physicians to measure acceptance of 2-liter containers. Time savings for 2-liter versus 1-liter containers were 7.33 and 3.06 minutes per 2-liter container for individual and batch processing, respectively. Nursing time saved with use of 2-liter containers was 2.79 minutes per 2-liter container. Total personnel and supply costs for 2-liter containers were $ 1.60 and $ 0.70 less per liter for individual and batch processing, respectively. For 2-liter TPN solutions prepared for 11 patients (129 patient days), waste was not significantly different than for the 1-liter control group. Questionnaire responses indicated overall acceptance of administration of 2-liter solutions as safe and efficient. For centrally administered TPN therapy in the inpatient setting, use of 2-liter flexible polyvinyl chloride containers is efficient and cost effective.

Completeness of physicians' orders for cancer chemotherapy was compared before and after implementation of a preprinted form for these orders. When an oncology pharmacy service (OPS) in which pharmacy prepared all drugs for cancer chemotherapy was implemented in 1985 at an 879-bed teaching hospital, the pharmacists began educational sessions for house-staff physicians on writing orders for cancer chemotherapy. Pharmacists assessed the effectiveness of these sessions by comparing completeness of orders written before implementation of the OPS with orders during a four-week period starting two months after implementation. Orders were checked for nine components: patient's diagnosis, height, weight, and body surface area and drug regimen, dose, dosage, frequency, and route. Inclusion of the same components was assessed after implementation of a form that physicians were required to use for prescribing all antineoplastic agents. During the baseline period, orders for 143 patients were evaluated. Only two prescription components, dose and route, were present is more than 90% of the orders. Educational intervention led to some improvement in order completeness, but only dose and route appeared in at least 90% of the 87 orders evaluated. The components necessary to verify physicians' calculations for body surface area and dose--height, weight, and dosage--were absent in 29 of the orders, and a pharmacist spent 420 minutes clarifying them. After the order form was implemented, orders for 77 patients were reviewed. Compliance exceeded 90% for eight of the nine components, and 12 medication errors were prevented by the form. A pharmacist spent 70 minutes clarifying five orders.(ABSTRACT TRUNCATED AT 250 WORDS)