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Branching ratios from B{sub s} and {Lambda}{sub b}{sup 0} (open access)

Branching ratios from B{sub s} and {Lambda}{sub b}{sup 0}

CDF Run II relative branching ratio measurements for 65 pb{sup -1} of data in the channels B{sub s} {yields} D{sub s}{sup {-+}}{pi}{sup {-+}}, {Lambda} {sub b}{sup 0} {yields} {Lambda}{sub c}{sup {+-}}{pi}{sup {-+}} and B {yields} h{sup +}h{sup -} are presented. Further, an observation of B{sub s} {yields} K{sup {+-}} K{sup {-+}} and a measurement of A{sub CP} are presented.
Date: May 28, 2004
Creator: Martin, Matthew S.
System: The UNT Digital Library
Functional self-assembling bolaamphiphilic polydiacetylenes as colorimetric sensor scaffolds (open access)

Functional self-assembling bolaamphiphilic polydiacetylenes as colorimetric sensor scaffolds

Conjugated polymers capable of responding to external stimuli by changes in optical, electrical or electrochemical properties can be used for the construction of direct sensing devices. Polydiacetylene-based systems are attractive for sensing applications due to their colorimetric response to changes in the local environment. Here we present the design, preparation and characterization of self-assembling functional bolaamphiphilic polydiacetylenes (BPDAs) inspired by Nature's strategy for membrane stabilization. We show that by placing polar headgroups on both ends of the diacetylene lipids in a transmembranic fashion, and altering the chemical nature of the polar surface residues, the conjugated polymers can be engineered to display a range of radiation-, thermal- and pH-induced colorimetric responses. We observed dramatic nanoscopic morphological transformations accompanying charge-induced chromatic transitions, suggesting that both side chain disordering and main chain rearrangement play important roles in altering the effective conjugation lengths of the poly(ene-yne). These results establish the foundation for further development of BPDA-based colorimetric sensors.
Date: May 28, 2004
Creator: Song, Jie; Cisar, Justin S. & Bertozzi, Carolyn R.
System: The UNT Digital Library
Ligand-field effects for the 3p photoelectron spectra of Cr2O3 (open access)

Ligand-field effects for the 3p photoelectron spectra of Cr2O3

This article discusses ligand-field effects for the 3p photoelectron spectra of Cr2O3.
Date: May 28, 2004
Creator: Bagus, Paul S.; Ilton, Eugene S. & Rustad, James R.
System: The UNT Digital Library
Autonomous Detection of Aerosolized Biological Agents by Multiplexed Immunoassay with PCR Confirmation (open access)

Autonomous Detection of Aerosolized Biological Agents by Multiplexed Immunoassay with PCR Confirmation

The autonomous pathogen detection system (APDS) is an automated, podium-sized instrument that continuously monitors the air for biological threat agents (bacteria, viruses, and toxins). The system has been developed to warn of a biological attack in critical or high-traffic facilities and at special events. The APDS performs continuous aerosol collection, sample preparation, and detection using multiplexed immunoassay followed by confirmatory PCR using real-time TaqMan assays. We have integrated completely reusable flow-through devices that perform DNA extraction and PCR amplification. The fully integrated system was challenged with aerosolized Bacillus anthracis, Yersinia pestis, Bacillus globigii and botulinum toxoid. By coupling highly selective antibody and DNA based assays, the probability of an APDS reporting a false positive is extremely low.
Date: May 27, 2004
Creator: Hindson, B. J.; McBride, M. T.; Makarewicz, A. J.; Henderer, B. D.; Setlur, U. S.; Smith, S. M. et al.
System: The UNT Digital Library
A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting. (open access)

A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting.

A stabilized equal-order velocity-pressure finite element algorithm is presented for the analysis of flow in porous media and in the solidification of binary alloys. The adopted governing macroscopic conservation equations of momentum, energy and species transport are derived from their microscopic counterparts using the volume-averaging method. The analysis is performed in a single domain with a fixed numerical grid. The fluid flow scheme developed includes SUPG (streamline-upwind/Petrov-Galerkin), PSPG (pressure stabilizing/Petrov-Galerkin) and DSPG (Darcy stabilizing/Petrov-Galerkin) stabilization terms in a variable porosity medium. For the energy and species equations a classical SUPG-based finite element method is employed. The developed algorithms were tested extensively with bilinear elements and were shown to perform stably and with nearly quadratic convergence in high Rayleigh number flows in varying porosity media. Examples are shown in natural and double diffusive convection in porous media and in the directional solidification of a binary-alloy.
Date: May 27, 2004
Creator: Dr. Zabaras, N. & Samanta, D.
System: The UNT Digital Library
Convergent Coarseness Regulation for Segmented Images (open access)

Convergent Coarseness Regulation for Segmented Images

In segmentation of remotely sensed images, the number of pixel classes and their spectral representations are often unknown a priori. Even with prior knowledge, pixels with spectral components from multiple classes lead to classification errors and undesired small region artifacts. Coarseness regulation for segmented images is proposed as an efficient novel technique for handling these problems. Beginning with an over-segmented image, perceptually similar connected regions are iteratively merged using a method reminiscent of region growing, except the primitives are regions, not pixels. Interactive coarseness regulation is achieved by specifying the area {alpha} of the largest region eligible for merging. A region with area less than {alpha} is merged with the most spectrally similar connected region, unless the regions are perceived as spectrally dissimilar. In convergent coarseness regulation, which requires no user interaction, {alpha} is specified as the total number of pixels in the image, and the coarseness regulation output converges to a steady-state segmentation that remains unchanged as {alpha} is further increased. By applying convergent coarseness regulation to AVIRIS, IKONOS and DigitalGlobe images, and quantitatively comparing computer-generated segmentations to segmentations generated manually by a human analyst, it was found that the quality of the input segmentations was consistently and dramatically …
Date: May 27, 2004
Creator: Paglieroni, D W
System: The UNT Digital Library
Discovery of New Eruptive Cataclysmic Variables using the MACHO Database (open access)

Discovery of New Eruptive Cataclysmic Variables using the MACHO Database

We report the results of a search in the MACHO light-curve database aiming to find new cataclysmic variables. The targets were selected from variables toward the Magellanic Clouds and Galactic bulge using as main criteria the amplitude of photometric variability and color indices. These criteria provided a total of 3720 variables, which were visually inspected for novae, recurrent novae or dwarf novae eruptions. Dwarf novae type outbursts were recognized in 28 objects while a second sample of 38 less probable candidates was also selected. Some characteristics of the light curves of the cataclysmic variables identified are described and, when possible, a classification in a subtype is assigned to the system. The coordinates of each selected target were cross correlated against X-ray survey databases in order to search for possible point source identifications. The detected dwarf novae in the direction of the bulge are probable members of the Galactic disk population.
Date: May 27, 2004
Creator: Cieslinski, D; Diaz, M P; Drake, A J & Cook, K H
System: The UNT Digital Library
An efficient parallel termination detection algorithm (open access)

An efficient parallel termination detection algorithm

Information local to any one processor is insufficient to monitor the overall progress of most distributed computations. Typically, a second distributed computation for detecting termination of the main computation is necessary. In order to be a useful computational tool, the termination detection routine must operate concurrently with the main computation, adding minimal overhead, and it must promptly and correctly detect termination when it occurs. In this paper, we present a new algorithm for detecting the termination of a parallel computation on distributed-memory MIMD computers that satisfies all of those criteria. A variety of termination detection algorithms have been devised. Of these, the algorithm presented by Sinha, Kale, and Ramkumar (henceforth, the SKR algorithm) is unique in its ability to adapt to the load conditions of the system on which it runs, thereby minimizing the impact of termination detection on performance. Because their algorithm also detects termination quickly, we consider it to be the most efficient practical algorithm presently available. The termination detection algorithm presented here was developed for use in the PMESC programming library for distributed-memory MIMD computers. Like the SKR algorithm, our algorithm adapts to system loads and imposes little overhead. Also like the SKR algorithm, ours is tree-based, …
Date: May 27, 2004
Creator: Baker, A H; Crivelli, S & Jessup, E R
System: The UNT Digital Library
Filtration of a Hanford Site Tank 241-AN-102 Waste Sample with Alternate Sr/TRU Precipitation Conditions at Bench and Pilot Scales (open access)

Filtration of a Hanford Site Tank 241-AN-102 Waste Sample with Alternate Sr/TRU Precipitation Conditions at Bench and Pilot Scales

In support of the design of the Hanford Waste Treatment Plant, the Savannah River Technology Center has conducted crossflow ultrafiltration tests on the bench scale with both a radioactive sample and simulants and at pilot scale with simulants. The waste tested was from Tank 241-AN-102, which underwent isotopic dilution with strontium nitrate to reduce the soluble (superscript 90)Sr concentration, and sodium permanganate precipitation to remove selected transuranic species. Experimental work validated the use of a simulant by comparison of bench scale simulant filtration data with radioactive filtration test data. Tests on a pilot scale were also conducted and showed that the filtration flux in the pilot unit was consistently lower than in the bench scale unit. An alternative precipitation method resulted in less filterable slurries. Several possible explanations for the differences in flux were proposed, including differences in particle size distribution and slurry viscosity (th e term viscosity will be used, although consistency is more correct for non-Newtonian fluids). The experimental data was also fit to an empirical model and several filtration models. The trends in the data generally followed the predictions of the filtration models. Differences in flux between the bench and pilot scales could not be accounted for …
Date: May 27, 2004
Creator: Zamecnik, John R.; Poirier, Michael R.; Duignan, Mark R.; Nash, Charles A. & Baich, Mark A.
System: The UNT Digital Library
Properties of RR Lyrae stars in the Inner Regions of the Large Magellanic Cloud (open access)

Properties of RR Lyrae stars in the Inner Regions of the Large Magellanic Cloud

We present the radial velocities, metallicities and the K-band magnitudes of 74 RR Lyrae stars in the inner regions of the LMC. The intermediated resolution spectra and the infrared images were obtained with FORS1 at the ESO VLT and with the SOFI infrared imager at the ESO NTT. The best 43 RR Lyrae with measured velocities yield an observed velocity dispersion of {sigma}=61{+-} 7 km s{sup -1}. We obtain a true LMC RR Lyrae velocity dispersion of {sigma}=53 km s{sup -1}, which is higher than the velocity dispersion of any other LMC population previously measured. This is the first empirical evidence for a kinematically hot, metal-poor halo in the LMC as discussed in Minniti et al. (2003). Using Layden's (1994) modification for the {Delta}S method we measured the metallicity for 23 of our stars. The mean value is [Fe/H]=-1.46{+-}0.09 dex. The absolute magnitudes M{sub v} and M{sub K} of RR Lyrae stars are linear functions of metallicity. In the V band, our data agree with the Olech et al. (2003) relation, in the K band the slope is flatter. The average apparent V luminosity of 70 RR Lyrae stars is <V>=19.45{+-}0.04 and the average K luminosity of 37 RR Lyrae …
Date: May 27, 2004
Creator: Borissova, J; Minniti, D; Rejkuba, M; Alves, D; Cook, K H & Freeman, K C
System: The UNT Digital Library
Quantitative models of subduction zone fluids: How hydrous phases in the slab determine the composition of subduction zone lavas (open access)

Quantitative models of subduction zone fluids: How hydrous phases in the slab determine the composition of subduction zone lavas

None
Date: May 27, 2004
Creator: Feineman, M; Ryerson, F J & DePaolo, D
System: The UNT Digital Library
Repair of Phase Defects in Extreme-Ultraviolet Lithography Mask Blanks (open access)

Repair of Phase Defects in Extreme-Ultraviolet Lithography Mask Blanks

None
Date: May 27, 2004
Creator: Hau-Riege, S.; Barty, A.; Mirkarimi, P.; Baker, S.; Coy, M.; Mita, M. et al.
System: The UNT Digital Library
Simulations Of Electron Transport For Fast Ignition Using LSP (open access)

Simulations Of Electron Transport For Fast Ignition Using LSP

A crucial issue for the viability of the fast ignition approach to inertial fusion energy is the transport of the ignition pulse energy from the critical surface to the high-density compressed fuel. Experiments have characterized this transport through the interaction of short pulse, high intensity lasers with solid-density targets containing thin K{sub alpha} fluorescence layers. These experiments show a reasonably well-collimated beam, although with a significantly larger radius than the incident laser beam. We report on LSP calculations of these experiments, which show reasonable agreement with the experimental observations.
Date: May 27, 2004
Creator: Town, R. J.; Chen, C.; Cottrill, L. A.; Key, M. H.; Kruer, W. L.; Langdon, A. B. et al.
System: The UNT Digital Library
Summary of workshop session F on electron-cloud instabilities (open access)

Summary of workshop session F on electron-cloud instabilities

We summarize Session F of the ECLOUD 04 workshop. This session was dedicated to beam instabilities driven by electron cloud. Specifically, we discuss the principal observations of electron-cloud instabilities, analytical models, simulation codes and the next steps that need to be taken to arrive at a predictive theory.
Date: May 27, 2004
Creator: Zimmermann, Frank & Wolski, Andrzej
System: The UNT Digital Library
Testing LMC Microlensing Scenarios: The Discrimination Power of the SuperMACHO Microlensing Survey (open access)

Testing LMC Microlensing Scenarios: The Discrimination Power of the SuperMACHO Microlensing Survey

Characterizing the nature and spatial distribution of the lensing objects that produce the observed microlensing optical depth toward the Large Magellanic Cloud (LMC) remains an open problem. They present an appraisal of the ability of the SuperMACHO Project, a next-generation microlensing survey pointed toward the LMC, to discriminate between various proposed lensing populations. they consider two scenarios: lensing by a uniform foreground screen of objects and self-lensing of LMC stars. The optical depth for ''screen-lensing'' is essentially constant across the face of the LMC; whereas, the optical depth for self-lensing shows a strong spatial dependence. they have carried out extensive simulations, based upon actual data obtained during the first year of the project, to assess the SuperMACHO survey's ability to discriminate between these two scenarios. In the simulations they predict the expected number of observed microlensing events for each of their fields by adding artificial stars to the images and estimating the spatial and temporal efficiency of detecting microlensing events using Monte-Carlo methods. They find that the event rate itself shows significant sensitivity to the choice of the LMC luminosity function shape and other parameters, limiting the conclusions which can be drawn from the absolute rate. By instead determining the …
Date: May 27, 2004
Creator: Rest, A.; Stubbs, C.; Becker, A. C.; Miknaitis, G. A.; Miceli, A.; Covarrubias, R. et al.
System: The UNT Digital Library
An algebraic sub-structuring method for large-scale eigenvaluecalculation (open access)

An algebraic sub-structuring method for large-scale eigenvaluecalculation

We examine sub-structuring methods for solving large-scalegeneralized eigenvalue problems from a purely algebraic point of view. Weuse the term "algebraic sub-structuring" to refer to the process ofapplying matrix reordering and partitioning algorithms to divide a largesparse matrix into smaller submatrices from which a subset of spectralcomponents are extracted and combined to provide approximate solutions tothe original problem. We are interested in the question of which spectralcomponentsone should extract from each sub-structure in order to producean approximate solution to the original problem with a desired level ofaccuracy. Error estimate for the approximation to the small esteigen pairis developed. The estimate leads to a simple heuristic for choosingspectral components (modes) from each sub-structure. The effectiveness ofsuch a heuristic is demonstrated with numerical examples. We show thatalgebraic sub-structuring can be effectively used to solve a generalizedeigenvalue problem arising from the simulation of an acceleratorstructure. One interesting characteristic of this application is that thestiffness matrix produced by a hierarchical vector finite elements schemecontains a null space of large dimension. We present an efficient schemeto deflate this null space in the algebraic sub-structuringprocess.
Date: May 26, 2004
Creator: Yang, C.; Gao, W.; Bai, Z.; Li, X.; Lee, L.; Husbands, P. et al.
System: The UNT Digital Library
High concentration suspended sediment measurments using acontinuous fiber optic in-stream transmissometer (open access)

High concentration suspended sediment measurments using acontinuous fiber optic in-stream transmissometer

Suspended sediment loads mobilized during high flow periods in rivers and streams are largely uncharacterized. In smaller and intermittent streams, a large storm may transport a majority of the annual sediment budget. Therefore monitoring techniques that can measure high suspended sediment concentrations at semi-continuous time intervals are needed. A Fiber optic In-stream Transmissometer (FIT) is presented for continuous measurement of high concentration suspended sediment in storm runoff. FIT performance and precision were demonstrated to be reasonably good for suspended sediment concentrations up to 10g/L. The FIT was compared to two commercially available turbidity devices and provided better precision and accuracy at both high and low concentrations. Both turbidity devices were unable to collect measurements at concentrations greater than 4 g/L. The FIT and turbidity measurements were sensitive to sediment particle size. Particle size dependence of transmittance and turbidity measurement poses the greatest problem for calibration to suspended sediment concentration. While the FIT was demonstrated to provide acceptable measurements of high suspended sediment concentrations, approaches to real-time suspended sediment detection need to address the particle size dependence in concentration measurements.
Date: May 26, 2004
Creator: Campbell, Chris G.; Laycak, Danny T.; Hoppes, William; Tran,Nguyen T. & Shi, Frank G.
System: The UNT Digital Library
Proceedings of Riken BNL Research Center Workshop: Volume 61 Riken-Todai Mini-Workshop on ''Topics in Hadron Physics at RHIC''. Volume 61 (open access)

Proceedings of Riken BNL Research Center Workshop: Volume 61 Riken-Todai Mini-Workshop on ''Topics in Hadron Physics at RHIC''. Volume 61

The RIKEN-TODAI Mini-Workshop on ''Topics in Hadron Physics at RHIC'' was held on March 23rd and 24th, 2064 at the Nishina Memorial Hall of RIKEN, Wako, Saitama, Japan, sponsored by RIKEN (Institute of Physical and Chemical Research) and TODAI (University of Tokyo). The workshop was planned when we learned that two distinguished theorists in hadron physics, Professors L. McLerran and S.H. Lee, would be visiting TODAI and/or RIKEN during the week of March 22-26. We asked them to give key talks at the beginning of the workshop and attend the sessions consisting of talks by young theorists in RIKEN, TODAI and other institutes in Japan and they kindly agreed on both. Considering the JPS meeting scheduled from March 27 through 30, we decided to have a.one-and-half-a-day workshop on March 23 and 24. The purpose of the workshop was to offer young researchers an opportunity to learn the forefront of hadron physics as well as to discuss their own works with the distinguished theorists.
Date: May 26, 2004
Creator: En'yo, H.; Hamagaki, H.; Hatsuda, T.; Watanaba, Y. & Yazaki, K.
System: The UNT Digital Library
Rating energy efficiency and sustainability in laboratories: Results and lessons from the Labs21 program (open access)

Rating energy efficiency and sustainability in laboratories: Results and lessons from the Labs21 program

Laboratories are very energy intensive, with significant opportunities for improved efficiency. However, their inherent complexity and variety makes benchmarking of their energy and environmental performance a unique and challenging task. Furthermore, laboratories have a myriad of health and safety requirements that significantly affect energy use, adding complexity to their benchmarking. The Labs21 program, a joint program of the US EPA and US DOE, has developed two resources specifically for assessing laboratory energy and environmental performance: (1) An energy benchmarking tool which allows users to compare laboratories using a standard set of building and system level energy use metrics. (2) The Environmental Performance Criteria (EPC) a point-based rating system that builds on the LEED(TM) green building rating system, designed to score overall environmental performance. In this paper, for each of these tools we present the underlying methodology and results from their use. For the benchmarking tool, we contrast our approach, which includes a simulation model-based component, with those used for other building types. We also present selected results from data collection and analysis of about 40 private and public sector laboratory facilities. In the case of the EPC, we describe variations from the LEED standard, focusing on the energy credits. Finally, …
Date: May 26, 2004
Creator: Mathew, Paul; Sartor, Dale; van Geet, Otto & Reilly, Sue
System: The UNT Digital Library
Reactive Transport Modeling of Cap Rock Integrity During Natural and Engineered CO2 Storage (open access)

Reactive Transport Modeling of Cap Rock Integrity During Natural and Engineered CO2 Storage

Long-term cap rock integrity represents the single most important constraint on the long-term isolation performance of natural and engineered CO{sub 2} storage sites. CO{sub 2} influx that forms natural accumulations and CO{sub 2} injection for EOR/sequestration or saline-aquifer disposal both lead to concomitant geochemical alteration and geomechanical deformation of the cap rock, enhancing or degrading its seal integrity depending on the relative effectiveness of these interdependent processes. Using our reactive transport simulator (NUFT), supporting geochemical databases and software (GEMBOCHS, SUPCRT92), and distinct-element geomechanical model (LDEC), we have shown that influx-triggered mineral dissolution/precipitation reactions within typical shale cap rocks continuously reduce microfracture apertures, while pressure and effective-stress evolution first rapidly increase then slowly constrict them. For a given shale composition, the extent of geochemical enhancement is nearly independent of key reservoir properties (permeability and lateral continuity) that distinguish EOR/sequestration and saline-aquifer settings and CO{sub 2} influx parameters (rate, focality, and duration) that distinguish engineered disposal sites and natural accumulations, because these characteristics and parameters have negligible (indirect) impact on mineral dissolution/precipitation rates. In contrast, the extent of geomechanical degradation is highly dependent on these reservoir properties and influx parameters because they effectively dictate magnitude of the pressure perturbation; specifically, initial geomechanical …
Date: May 26, 2004
Creator: Johnson, J. W.; Nitao, J. J. & Morris, J. P.
System: The UNT Digital Library
Real Time Pricing and the Real Live Firm (open access)

Real Time Pricing and the Real Live Firm

Energy economists have long argued the benefits of real time pricing (RTP) of electricity. Their basis for modeling customers response to short-term fluctuations in electricity prices are based on theories of rational firm behavior, where management strives to minimize operating costs and optimize profit, and labor, capital and energy are potential substitutes in the firm's production function. How well do private firms and public sector institutions operating conditions, knowledge structures, decision-making practices, and external relationships comport with these assumptions and how might this impact price response? We discuss these issues on the basis of interviews with 29 large (over 2 MW) industrial, commercial, and institutional customers in the Niagara Mohawk Power Corporation service territory that have faced day-ahead electricity market prices since 1998. We look at stories interviewees told about why and how they respond to RTP, why some customers report that they can't, and why even if they can, they don't. Some firms respond as theorized, and we describe their load curtailment strategies. About half of our interviewees reported that they were unable to either shift or forego electricity consumption even when prices are high ($0.50/kWh). Reasons customers gave for why they weren't price-responsive include implicit value placed on …
Date: May 26, 2004
Creator: Moezzi, Mithra; Goldman, Charles; Sezgen, Osman; Bharvirkar, Ranjit & Hopper, Nicole
System: The UNT Digital Library
Superbend upgrade of the Advanced Light Source (open access)

Superbend upgrade of the Advanced Light Source

The Advanced Light Source (ALS) is a third generation synchrotron light source located at Lawrence Berkeley National Laboratory (LBNL). There was an increasing demand at the ALS for additional high brightness hard x-ray beamlines in the 7 to 40 keV range. In response to that demand, the ALS storage ring was modified in August 2001. Three 1.3 Tesla normal conducting bending magnets were removed and replaced with three 5 Tesla superconducting magnets (Superbends). The radiation produced by these Superbends is an order of magnitude higher in photon brightness and flux at 12 keV than that of the 1.3 Tesla bends, making them excellent sources of hard x-rays for protein crystallography and other hard x-ray applications. At the same time the Superbends did not compromise the performance of the facility in the VUV and soft x-ray regions of the spectrum. The Superbends will eventually feed 12 new beamlines greatly enhancing the facility's capability and capacity in the hard x-ray region. The Superbend project is the biggest upgrade to the ALS storage ring since it was commissioned in 1993. In this paper we present an overview of the Superbend project, its challenges and the resulting impact on the ALS.
Date: May 26, 2004
Creator: Robin, D.; Krupnick, J.; Schlueter, R.; Steier, C.; Marks, S.; Wang, B. et al.
System: The UNT Digital Library
Analytic Expressions for Optimal ICF Hohlraum Wall Density and Wall Loss (open access)

Analytic Expressions for Optimal ICF Hohlraum Wall Density and Wall Loss

Solutions to the radiation diffusion equation predict the absorbed energy (''wall loss'') within an inertial confinement fusion (ICF) hohlraum. Comparing supersonic vs. subsonic solutions suggests that a high Z metallic foam as hohlraum wall material will reduce hydrodynamic losses, and hence, net absorbed energy by {approx}20%. We derive an analytic expression for the optimal density (for any given drive temperature and pulse-length) that will achieve this reduction factor and which agrees well with numerical simulations. This approach can reduce the cost of a reactor driver. Radiation heat waves, or Marshak waves, play an important role in energy transport and in the energy balance of laser, z-pinch and heavy ion beam hohlraums for ICF and high energy density physics experiments. In these experiments, a power source, e.g. a laser, delivers energy to the interior of a high Z cavity that is converted to x-rays. Typically, most of the energy is absorbed in a thin, diffusively heated layer on the hohlraum interior surface, and re-emission from the heated layer sets the radiation temperature T achieved in the hohlraum. In our recent paper, (henceforward referred to as HR) we developed an analytic theory of Marshak waves via a perturbation theory using a small …
Date: May 25, 2004
Creator: Rosen, M D & Hammer, J H
System: The UNT Digital Library
Calculating Expectations with Time-Dependent Perturbations in Quantum Monte Carlo (open access)

Calculating Expectations with Time-Dependent Perturbations in Quantum Monte Carlo

None
Date: May 25, 2004
Creator: Kalos, M H & de Saavedra, F A
System: The UNT Digital Library