[en] Multi-keV x-ray microscopy will be an important laser-produced plasma diagnostic at future megajoule facilities such as the National Ignition Facility (NIF).In preparation for the construction of this facility, we have investigated several instrumentation options in detail, and we conclude that near normal incidence single spherical or toroidal crystals may offer the best general solution for high-energy x-raymicroscopy at NIF and at similar large facilities. Kirkpatrick-Baez microscopes using multi-layer mirrors may also be good secondary options, particularly if apertures are used to increase the band-width limited field of view

[en] The proposed National Ignition Facility (NIF) is a large (1.8 MJ on target at 0.35 microm) multi-beam laser facility that will be used for Inertial Confinement Fusion (ICF). ICF implosions at this facility will produce core plasma temperatures over 10 keV and densities over 100 g/cm³. Properties of these plasmas can be measured by a variety of optical, x-ray, and nuclear diagnostic techniques such as those used at existing facilities like the Nova laser at the Lawrence Livermore National Laboratory (LLNL). Some of these currently used techniques will be directly applicable to NIF; others require significant development. Damage of components close to the target will be a much greater issue at NIF, necessitating the development of distant detector techniques. To penetrate the larger targets, x-ray-based core diagnostics will need to utilize substantially higher energies than are in routine use today. Penetrating nuclear-particle-based diagnostics will be particularly well suited to these implosions, and the higher nuclear yields will allow new techniques to be developed. Some examples of diagnostics used for high-density-implosion experiments at Nova and corresponding development of new techniques for NIF are discussed

[en] Phosphorylation of hepatic cytochrome P-450 was studied in isolated hepatocytes incubated in the presence of agents known to stimulate protein kinase activity. Incubation of hepatocytes isolated from phenobarbital-induced adult male rats with [³²P]orthophosphate in the presence of N⁶, O^2'-dibutyryl-cAMP (diBtcAMP) or glucagon resulted in the phosphorylation of microsomal proteins that are immunoprecipitable by polyclonal antibodies raised to the phenobarbital-induced P-450 form PB-4 (P-450 gene IIB1). Two-dimensional gel electrophoresis revealed that these ³²P-labeled microsomal proteins consist of a mixture of P-450 PB-4 and the closely related P-450 PB-5 (gene IIB2), both of which exhibited heterogeneity in the isoelectric focusing dimension. Phosphorylation of both P-450 forms was markedly enhanced by diBtcAMP at concentrations as low as 5 μM. Phosphoamino acid analysis of the ³²P-labeled P-450 PB-4 + PB-5 immunoprecipitate revealed that these P-450s are phosphorylated on serine in the isolated hepatocytes. Peptide mapping indicated that the site of phosphorylation in hepatocytes is indistinguishable from the site utilized by cAMP-dependent protein kinase in vitro, which was previously identified as serine-128 for the related rabbit protein P-450 LM2. In vitro analyses revealed that phosphorylation of P-450 PB-4 leads to a loss of monooxygenase activity, suggesting that the posttranslational modification of this P-450 enzyme by cAMP-dependent protein kinase may play a role in the modulation of P-450-dependent monooxygenase activity in vivo

[en] We are studying the feasibility of utilizing Kα x-ray sources in the range of 20 to 100 keV as a backlighters for imaging various stages of implosions and high areal density planar samples driven by the NIF laser facility. The hard x-ray Kα sources are created by relativistic electron plasma interactions in the target material after a radiation by short pulse high intensity lasers. In order to understand Kα source characteristics such as production efficiency and brightness as a function of laser parameters, we have performed experiments using the 10 J, 100 fs JanUSP laser. We utilized single-photon counting spectroscopy and x-ray imaging diagnostics to characterize the Kα source. We find that the Kα conversion efficiency from the laser energy is ∼ 3 x 10^-4

[en] We report the first neutron data for a single crystal Chemical Vapor Deposition diamond sensor. Results are presented for 2.5, 14.1, and 14.9 MeV incident neutrons. We show that the energy resolution for 14.1 MeV neutrons is at least 2.9% (as limited by the energy spread of the incident neutrons), and perhaps as good as 0.4% (as extrapolated from high resolution α-particle data). This result could be relevant to fusion neutron spectroscopy at machines like the International Thermonuclear Experimental Reactor. We also show that our sensor has a high neutron linear attenuation coefficient, due to the high atomic density of diamond, and this could lead to applications in fission neutron detection

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[en] X-ray imaging will be an important diagnostic tool for inertial confinement fusion (ICF) research at the National Ignition Facility (NIF). However, high neutron yields will make X-ray imaging much more difficult than it is at current smaller facilities. We analyze the feasibility and performance of an Ignition X-Ray Imager to be used on cryogenic D-T implosions at NIF. The system is intended to provide time-integrated, broadband, moderate-energy X-ray core images of imploding ICF capsules. Highly magnified, spectrally-filtered images created using an array of pinholes placed close to the target will be projected onto a scintillator placed at the target chamber wall. A telescope will be used to relay the scintillator emission to a distant optical detector that is time-gated in order to minimize backgrounds, in particular from neutrons. The system is optimized with respect to spatial-resolution, signal-to-background and signal-to-noise ratios. (authors)

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