In this contribution the authors discuss the physics of strange hadrons in low energy ({approx_equal} 1-2 AGeV) heavy ion collision. In this energy range the relevant strange particle are the kaons and anti-kaons. The most interesting aspect concerning these particles are so called in-medium modifications. They will attempt to review the current status of understanding of these in medium modifications. In addition they briefly discuss other issues related with kaon production, such as the nuclear equation of state and chemical equilibrium.

This chapter provides an overview of some recent research activities on the study of optical and dynamic properties of semiconductor nanomaterials. The emphasis is on unique aspects of these properties in nanostructures as compared to bulk materials. Linear, including absorption and luminescence, and nonlinear optical as well as dynamic properties of semiconductor nanoparticles are discussed with focus on their dependence on particle size, shape, and surface characteristics. Both doped and undoped semiconductor nanomaterials are highlighted and contrasted to illustrate the use of doping to effectively alter and probe nanomaterial properties. Some emerging applications of optical nanomaterials are discussed towards the end of the chapter, including solar energy conversion, optical sensing of chemicals and biochemicals, solid state lighting, photocatalysis, and photoelectrochemistry.

A Bayesian inference methodology using a Markov Chain Monte Carlo (MCMC) sampling procedure is presented for estimating the parameters of computational structural models. This methodology combines prior information, measured data, and forward models to produce a posterior distribution for the system parameters of structural models that is most consistent with all available data. The MCMC procedure is based upon a Metropolis-Hastings algorithm that is shown to function effectively with noisy data, incomplete data sets, and mismatched computational nodes/measurement points. A series of numerical test cases based upon a cantilever beam is presented. The results demonstrate that the algorithm is able to estimate model parameters utilizing experimental data for the nodal displacements resulting from specified forces.

For the National Ignition Facility, at the Lawrence Livermore National Laboratory, nanoporous structures play a crucial role in the development of targets for high energy density experiments. Here we present a new bottom-up synthesis technique termed filter-casting for the creation of bimodal macro/nanoporous Cu structures. Homogeneous nanoporous monoliths can be synthesized using Cu nanoparticles and bimodal porosities can be achieved using sacrificial polystyrene spheres as a template. Control over the structure and composition is critical for target manufacturing. The measured densities of the Cu foam range between 1070-3390 mg/cm{sup 3}. Filter-casting is a powerful new method for directly synthesizing large nanoporous monoliths with predetermined composition, pore size, and pore structure.

Neutron imaging systems measure the spatial distribution of neutron emission from burning inertial confinement fusion (ICF) targets. These systems use a traditional pinhole geometry to project an image of the source onto a two-dimensional scintillator array, and a CCD records the resulting scintillation image. The recent history of ICF neutron images has produced images with qualities that have improved as the fusion neutron yields have increased to nearly 10{sup 14} neutrons. Anticipated future neutron yields in excess of 10{sup 16} at the National Ignition Facility and LMJ have raised the prospect of neuron imaging diagnostics which simultaneously probe several different characteristics of burning fusion targets. The new measurements rely on gated-image recording to select images corresponding to specific bands of neutron energies. Gated images of downscattered neutrons with energies from 5 to 8 MeV can emphasize regions of the target which contain DT fuel which is not burning. At the same time, gated images which select different portions of the 14-MeV spectral peak can produce spatial temperature maps of a burning target. Since the neutron production depends on the DT fuel density and temperature, simultaneous images of temperature and neutron emission can be combined to infer the an image of …

In coherent anti-Stokes Raman scattering spectroscopy (CARS) experiments, usually the amplitude of the signal is measured and the phase information is lost. With a polarization- and phase-controlled pulse shaping technique, the relative phase between the resonant and non-resonant CARS signals is controlled, and spectral interferometry is performed without an interferometer. Both the real and imaginary parts of the background-free resonant CARS spectrum are measured via spectral interferometry between the resonant and non-resonant signals from the same sample. The resonant signal is amplified significantly by homodyne mixing with the non-resonant signal as a local oscillator, greatly improving the detection limit.

A simple device integrating a thin film support and a standard microcentrifuge tube can be used for making solutions of accurately known concentration of any organic compound in a single step, avoiding serial dilution and the use of microgram balances. Nanogram to microgram quantities of organic material deposited on the thin film are quantified by ion energy loss and transferred to the microcentrifuge tube with high recovery.

Radiative corrections to E1 matrix elements for ns-np transitions in the alkali metal atoms lithium through francium are evaluated. They are found to be small for the lighter alkalis but significantly larger for the heavier alkalis, and in the case of cesium much larger than the experimental accuracy. The relation of the matrix element calculation to a recent decay rate calculation for hydrogenic ions is discussed, and application of the method to parity nonconservation in cesium is described.

Iron spectra have been recorded from plasmas created at three different laser plasma facilities, the Tor Vergata University laser in Rome (Italy), the Hercules laser at ENEA in Frascati (Italy), and the Compact Multipulse Terawatt (COMET) laser at LLNL in California (USA). The measurements provide a means of identifying dielectronic satellite lines from FeXVI and FeXV in the vicinity of the strong 2p {yields} 3d transitions of FeXVII. About 80 {Delta}n {ge} 1 lines of FeXV (Mg-like) to FeXIX (O-like) were recorded between 13.8 to 17.1 {angstrom} with a high spectral resolution ({lambda}/{Delta}{lambda} {approx} 4000), about thirty of these lines are from FeXVI and FeXV. The laser produced plasmas had electron temperatures between 100 to 500 eV and electron densities between 10{sup 20} to 10{sup 22} cm{sup -3}. The Hebrew University Lawrence Livermore Atomic Code (HULLAC) was used to calculate the atomic structure and atomic rates for FeXV to FeXIX. HULLAC was used to calculate synthetic line intensities at T{sub e} = 200 eV and n{sub e} = 10{sup 21}cm{sup -3} for three different conditions to illustrate the role of opacity: optically thin plasmas with no excitation-autoionization/dielectronic recombination (EA/DR) contributions to the line intensities, optically thin plasmas that included EA/DR …

The DARHT TI accelerator uses a pulsed high current electron beam and Eiremsstrahlung converter target to generate an intense x-ray source for radiography. For the past several years, we have been performing an investigation of the possible adverse effects of (1) backstreaming ion emission from the Bremsstrahlung converter target and (2) the interaction of the resultant plasma with the electron beam during subsequent pulses. These effects would manifest themselves in a static focusing system as a rapidly varying x-ray spot. To study these effects, we are conducting beam-target interaction experiments on the ETA-I1 accelerator (a 6.0 MeV, 2.5 kA, 70 ns FWHM pulsed induction LINAC). We have determined spot dynamics and characterized the resultant plasma for various configurations. Our experiments show that the first effect is not strongly present when the beam initially interacts with the target. Electron beam pulses delivered to the target after formation of a plasm are strongly affected, however. We have also performed initial experiments to determine the effect of the beam propagating through the plasma. This data shows that the head of the beam is relatively robust, but that backstreaming ions from the plasma can induce a dynamic focus toward the tail of the beam. …

In this paper we report on a high-order fast method to numerically calculate convolution integral with smooth non-periodic kernel. This method is based on the Newton-Cotes quadrature rule for the integral approximation and an FFT method for discrete summation. The method can have an arbitrarily high-order accuracy in principle depending on the number of points used in the integral approximation and a computational cost of O(Nlog(N)), where N is the number of grid points. For a three-point Simpson rule approximation, the method has an accuracy of O(h{sup 4}), where h is the size of the computational grid. Applications of the Simpson rule based algorithm to the calculation of a one-dimensional continuous Gauss transform and to the calculation of a two-dimensional electric field from a charged beam are also presented.

We present the first results from a long (496 ks) Chandra High Energy Transmission Grating observation of the intermediate polar EX Hydrae. In addition to the narrow emission lines from the cooling post-shock gas, for the first time we have detected a broad component in some of the X-ray emission lines, namely O VIII {lambda}18.97, Mg XII {lambda}8.42, Si XIV {lambda}6.18, and Fe XVII {lambda}16.78. The broad and narrow components have widths of {approx} 1600 km s{sup -1} and {approx} 150 km s{sup -1}, respectively. We also find that the flux of the broad component is modulated at the white dwarf spin period, constraining the region where the gas is formed. We propose a scenario where the broad component is formed in the pre-shock flow photoionized by radiation from the post-shock flow. Because the photoionized region has to be close to the radiation source in order to produce strong photoionized emission lines from ions like O VIII, Mg XII, and Si XIV, our photoionization model constrains the height of the standing shock above the white dwarf surface.

We extend our earlier model for Rayleigh-Taylor and Richtmyer-Meshkov instabilities to the more general class of hydrodynamic instabilities driven by a time-dependent acceleration g(t) . Explicit analytic solutions for linear as well as nonlinear amplitudes are obtained for several g(t)'s by solving a Schroedinger-like equation d{sup 2}{eta}/dt{sup 2} - g(t)kA{eta} = 0 where A is the Atwood number and k is the wavenumber of the perturbation amplitude {eta}(t). In our model a simple transformation k {yields} k{sub L} and A {yields} A{sub L} connects the linear to the nonlinear amplitudes: {eta}{sup nonlinear} (k,A) {approx} (1/k{sub L})ln{eta}{sup linear} (k{sub L}, A{sub L}). The model is found to be in very good agreement with direct numerical simulations. Bubble amplitudes for a variety of accelerations are seen to scale with s defined by s = {integral} {radical}g(t)dt, while spike amplitudes prefer scaling with displacement {Delta}x = {integral}[{integral}g(t)dt]dt.

To ensure safe storage, plutonium-bearing oxides are stabilized at 950 C for at least two hours in an oxidizing atmosphere. Stabilization conditions are expected to decompose organic impurities, convert metals to oxides, and result in moisture content below 0.5 wt%. During stabilization, the specific surface area is reduced, which minimizes readsorption of water onto the oxide surface. Plutonium oxides stabilized according to these criteria were sampled and analyzed to determine moisture content and surface area. In addition, samples were leached in water to identify water-soluble chloride impurity content. Results of these analyses for seven samples showed that the stabilization process produced low moisture materials (< 0.2 wt %) with low surface area ({le} 1 m{sup 2}/g). For relatively pure materials, the amount of water per unit surface area corresponded to 1.5 to 3.5 molecular layers of water. For materials with chloride content > 360 ppm, the calculated amount of water per unit surface area increased with chloride content, indicating hydration of hygroscopic salts present in the impure PuO{sub 2}-containing materials. The low moisture, low surface area materials in this study did not generate detectable hydrogen during storage of four or more years.

Recent observations by atmospheric Cherenkov telescopes such as H.E.S.S. and MAGIC have revealed a large number of new sources of very-high-energy (VHE) gamma-rays above 100 GeV, mostly concentrated along the Galactic plane. At lower energies (100 MeV - 10 GeV) the satellite-based instrument EGRET revealed a population of sources clustering along the Galactic Plane. Given their adjacent energy bands a systematic correlation study between the two source classes seems appropriate. While only a few of the sources connect, both in terms of positional coincidence and spectral consistency, most of the detections occur only in one or the other energy domain. In these cases, for the first time consistent upper limits in the other energy band have been derived. Here, the populations of Galactic sources in both energy domains are characterized on observational as well as on theoretical grounds, followed by an interpretation on their similarities and differences. The observational data at this stage suggest rather different major source populations at GeV and TeV energies. With regards to preparations for the upcoming GLAST mission that will cover the energy range bridging GeV and TeV instruments this paper investigates the connection between the population of sources in these bands and concludes with …

We use the GEANT4 Monte Carlo framework to calculate the {gamma}-ray albedo of the Moon due to interactions of cosmic ray (CR) nuclei with moon rock. Our calculation of the albedo spectrum agrees with the EGRET data. We show that the spectrum of {gamma}-rays from the Moon is very steep with an effective cutoff around 3-4 GeV (600 MeV for the inner part of the Moon disk) and exhibits a narrow pion-decay line at 67.5 MeV, perhaps unique in astrophysics. Apart from other astrophysical sources, the albedo spectrum of the Moon is well understood, including its absolute normalization; this makes it a useful 'standard candle' for {gamma}-ray telescopes. The steep albedo spectrum also provides a unique opportunity for energy calibration of {gamma}-ray telescopes, such as the forthcoming Gamma Ray Large Area Space Telescope (GLAST). Since the albedo flux depends on the incident CR spectrum which changes over the solar cycle, it is possible to monitor the CR spectrum using the albedo {gamma}-ray flux. Simultaneous measurements of CR proton and helium spectra by the Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics (PAMELA), and observations of the albedo {gamma}-rays by the GLAST Large Area Telescope (LAT), can be used to test the …

The small beam sizes at the interaction point of a X-band linear collider require mechanical stabilization of the final focus magnets at the nanometer level. While passive systems provide adequate performance at many potential sites, active mechanical stabilization is useful if the natural or cultural ground vibration is higher than expected. A mechanical model of a room temperature linear collider final focus magnet has been constructed and actively stabilized with an accelerometer based system.

The gas phase is generally ignored in remediation of metals and radionuclides because it is assumed that there is no efficient way to exploit it. In the literal sense, all remediations involve the gas phase because this phase is linked to the liquid and solid phases by vapor pressure and thermodynamic relationships. Remediation methods that specifically use the gas phase as a central feature have primarily targeted volatile organic contaminants, not metals and radionuclides. Unlike many organic contaminants, the vapor pressure and Henry's Law constants of metals and radionuclides are not generally conducive to direct air stripping of dissolved contaminants. Nevertheless, the gas phase can play an important role in remediation of inorganic contaminants and provide opportunities for efficient, cost effective remediation. The objective here is to explore ways in which manipulation of the gas phase can be used to facilitate remediation of metals and radionuclides.

The interface between hafnium oxide grown by atomic layer deposition and (100) GaAs treated with HCl cleaning and (NH{sub 4}){sub 2}S passivation has been characterized. Synchrotron radiation photoemission core level spectra indicated successful removal of the native oxides and formation of passivating sulfides on the GaAs surface. Layer-by-layer removal of the hafnia film revealed a small amount of As{sub 2}O{sub 3} formed at the interface during the dielectric deposition. Traces of arsenic and sulfur out-diffusion into the hafnia film were observed after a 450 C post-deposition anneal, and may be the origins for the electrically active defects. Transmission electron microscopy cross section images showed thicker HfO{sub 2} films for a given precursor exposure on S-treated GaAs versus the non-treated sample. In addition, the valence-band and the conduction-band offsets at the HfO{sub 2}/GaAs interface were deduced to be 3.18 eV and a range of 0.87-0.97 eV, respectively. It appears that HCl+(NH{sub 4})2{sub S} treatments provide a superior chemical passivation for GaAs and initial surface for ALD deposition.

Retrieval in a multimedia database usually involves combining information from different modalities of data, such as text and images. However, all modalities of the data may not be available to form the query. The retrieval results from such a partial query are often less than satisfactory. In this paper, we present an approach to complete a partial query by estimating the missing features in the query. Our experiments with a database of images and their associated captions show that, with an initial text-only query, our completion method has similar performance to a full query with both image and text features. In addition, when we use relevance feedback, our approach outperforms the results obtained using a full query.

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We present measurements of the inclusive semileptonic branching fractions of charged and neutral B mesons using 20.6 fb-1 of data measured at the Upsilon(4S) with the BABAR detector. Events are tagged with a fully reconstructed hadronic decay of a B meson. The correlation between the flavor of the tag B meson and the electron charge allows the separation of prompt semileptonic B decays and cascade semileptonic charm decays. We obtain the preliminary inclusive semileptonic branching fraction of charged B mesons b+ = 0.103+/-0.006+/-0.005, neutral B mesons b0 = 0.104+/-0.008+/-0.005, their average b = 0.104+/-0.005+/-0.004, and their ratio b+/b0 = 0.99+/-0.10+/-0.03.

CsBr/Cr photocathodes were found [1,2] to meet the requirements of a multi-electron beam lithography system operating with a light energy of 4.8 eV (257nm). The fact that photoemission was observed with a light energy below the reported 7.3 eV band gap for CsBr was not understood. This paper presents experimental results on the presence of intra-band gap absorption sites (IBAS) in CsBr thin film photo electron emitters, and presents a model based on IBAS to explain the observed photoelectron emission behavior at energies below band gap. A fluorescence band centered at 330 nm with a FWHM of about 0.34 eV was observed in CsBr/Cr samples under 257 nm laser illumination which can be attributed to IBAS and agrees well with previously obtained synchrotron photoelectron spectra[1] from the valence band of CsBr films.

Using BABAR measurements of the inclusive electron spectrum in B {yields} X{sub u}e{nu} decays and the inclusive photon spectrum in B {yields} X{sub s}{gamma} decays, we extract the magnitude of the CKM matrix element V{sub ub}. The extraction is based on theoretical calculations designed to reduce the theoretical uncertainties by exploiting the assumption that the leading shape functions are the same for all b {yields} q transitions (q is a light quark). The results agree well with the previous analysis, have indeed smaller theoretical errors, but are presently limited by the knowledge of the photon spectrum and the experimental errors on the lepton spectrum.