Proceedings of RIKEN BNL Research Center Workshop, Volume 91, RBRC Scientific Review Committee Meeting (open access)

Proceedings of RIKEN BNL Research Center Workshop, Volume 91, RBRC Scientific Review Committee Meeting

The ninth evaluation of the RIKEN BNL Research Center (RBRC) took place on Nov. 17-18, 2008, at Brookhaven National Laboratory. The members of the Scientific Review Committee (SRC) were Dr. Dr. Wit Busza (Chair), Dr. Miklos Gyulassy, Dr. Akira Masaike, Dr. Richard Milner, Dr. Alfred Mueller, and Dr. Akira Ukawa. We are pleased that Dr. Yasushige Yano, the Director of the Nishina Institute of RIKEN, Japan participated in this meeting both in informing the committee of the activities of the Nishina Institute and the role of RBRC and as an observer of this review. In order to illustrate the breadth and scope of the RBRC program, each member of the Center made a presentation on his/her research efforts. This encompassed three major areas of investigation, theoretical, experimental and computational physics. In addition the committee met privately with the fellows and postdocs to ascertain their opinions and concerns. Although the main purpose of this review is a report to RIKEN Management (Dr. Ryoji Noyori, RIKEN President) on the health, scientific value, management and future prospects of the Center, the RBRC management felt that a compendium of the scientific presentations are of sufficient quality and interest that they warrant a wider distribution. …
Date: November 17, 2008
Creator: Samios, N. P.
System: The UNT Digital Library
Ion Deflection for Final Optics In Laser Inertial Fusion Power Plants (open access)

Ion Deflection for Final Optics In Laser Inertial Fusion Power Plants

Left unprotected, both transmissive and reflective final optics in a laser inertial fusion power plant would quickly fail from melting, pulsed thermal stresses, or degradation of optical properties as a result of ion implantation. One potential option for mitigating this threat is to magnetically deflect the ions such that they are directed into a robust energy dump. In this paper we detail integrated studies that have been carried out to asses the viability of this approach for protecting final optics.
Date: November 17, 2006
Creator: Abbott, R P & Latkowski, J F
System: The UNT Digital Library
Progress on the High Current Superconducting Injector and Energy Recovery Linac at BNL (open access)

Progress on the High Current Superconducting Injector and Energy Recovery Linac at BNL

None
Date: November 17, 2008
Creator: Ben-Zvi, Ilan
System: The UNT Digital Library
Risk Informing the Nuclear Materials and Waste Arenas. (open access)

Risk Informing the Nuclear Materials and Waste Arenas.

None
Date: November 17, 2002
Creator: Bari, R. A.; Mubayi, V.; Azarm, M. A.; Grove, E. J.; Xu, J.; Bailey, M. G. et al.
System: The UNT Digital Library
Engineering Design and Fabrication of an Ampere-Class Superconducting Photocathode Electron Gun (open access)

Engineering Design and Fabrication of an Ampere-Class Superconducting Photocathode Electron Gun

Over the past three years, Advanced Energy Systems and Brookhaven National Laboratory (BNL) have been collaborating on the design of an Ampere- class superconducting photocathode electron gun. BNL performed the physics design of the overall system and RF cavity under prior programs. Advanced Energy Systems (AES) is currently responsible for the engineering design and fabrication of the electron gun under contract to BNL. We will report on the engineering design and fabrication status of the superconducting photocathode electron gun. The overall configuration of the cryomodule will be reviewed. The layout of the hermitic string, space frame, shielding package, and cold mass will be discussed. The engineering design of the gun cavity and removable cathode will be presented in detail and areas of technical risk will be highlighted. Finally, the fabrication sequence and fabrication status of the gun cavity will be discussed.
Date: November 17, 2008
Creator: Ben-Zvi, Ilan
System: The UNT Digital Library
Design and Fabrication of the RHIC Electron-Cooling Experiment High Beta Cavity and Cryomodule (open access)

Design and Fabrication of the RHIC Electron-Cooling Experiment High Beta Cavity and Cryomodule

The summary of this report is: (1) A high-current SRF cavity for an Energy Recovery Linac (ERL) has been designed by BNL and AES and fabricated by AES; (2) The cavity was cleaned and tested by JLAB with BNL personnel support; (3) Cavity performance exceeded goal of 20 MV/m at Q{sub 0} > 1 x 10{sup 10} and far exceeded requirement of 15 MV/m at Q{sub 0} > 1 x 10{sup 10}; (4) Hermetic String assembled at JLAB with BNL personnel support and shipped to BNL; and (5) BNL has recently completed Cryomodule assembly and unit is ready for installation in the ERL vault.
Date: November 17, 2008
Creator: Holmes, D.; Calderaro, M.; Cole, M.; Falletta, M.; Peterson, E.; Rathke, J. et al.
System: The UNT Digital Library
Nondipole effects in the photoionization of Xe 4d5/2 and 4d3/2: Evidence for quadrupole satellites (open access)

Nondipole effects in the photoionization of Xe 4d5/2 and 4d3/2: Evidence for quadrupole satellites

Strong evidence for the existence and importance of quadrupole satellite transitions is found in spin-orbit-resolved Xe 4d nondipole photoionization in a combined experimental/theoretical study.
Date: November 17, 2003
Creator: Manson, S T; Johnson, W R; Lindle, D W; Rolles, D.; Cheng, K T; Zhou, H L et al.
System: The UNT Digital Library
Imaging Single ZnO Vertical Nanowire Laser Cavities using UV-Laser Scanning Confocal Microscopy (open access)

Imaging Single ZnO Vertical Nanowire Laser Cavities using UV-Laser Scanning Confocal Microscopy

We report the fabrication and optical characterization of individual ZnO vertical nanowire laser cavities. Dilute nanowire arrays with interwire spacing>10 ?m were produced by a modified chemical vapor transport (CVT) method yielding an ideal platform for single nanowire imaging and spectroscopy. Lasing characteristics of a single vertical nanowire are presented, as well as high-resolution photoluminescence imaging by UV-laser scanning confocal microscopy. In addition, three-dimensional (3D) mapping of the photoluminescence emission performed in both planar and vertical dimensions demonstrates height-selective imaging useful for vertical nanowires and heteronanostructures emerging in the field of optoelectronics and nanophotonics.
Date: November 17, 2008
Creator: Gargas, D. J.; Toimil-Molares, M. E. & Yang, P.
System: The UNT Digital Library
ASSESSMENTOF BETA PARTICLE FLUX FROM SURFACE CONTAMINATION AS A RELATIVE INDICATOR FOR RADIONUCLIDE DISTRIBUTION ON EXTERNAL SURFACES OF A MULTI-STORY BUILDING IN PRIPYAT (open access)

ASSESSMENTOF BETA PARTICLE FLUX FROM SURFACE CONTAMINATION AS A RELATIVE INDICATOR FOR RADIONUCLIDE DISTRIBUTION ON EXTERNAL SURFACES OF A MULTI-STORY BUILDING IN PRIPYAT

How would we recover if a Radiological Dispersion Device (e.g., dirty bomb) or Improvised Nuclear Device were to detonate in a large city? In order to assess the feasibility of remediation following such an event, several issues would have to be considered, including the levels and characteristics of the radioactive contamination, the availability of the required resources to accomplish decontamination, and the planned future use of the city's structures and buildings. Presently little is known about the distribution, redistribution, and migration of radionuclides in an urban environment. However, Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident, may provide some answers. The main objective of this study was to determine the radionuclide distribution on a Pripyat multi-story building, which had not been previously decontaminated and therefore could reflect the initial fallout and its further natural redistribution on external surfaces. The 7-story building selected was surveyed from the ground floor to the roof on horizontal and vertical surfaces along seven ground-to-roof transections. Some of the results from this study indicate that the upper floors of the building had higher contamination levels than the lower floors. The authors consequently recommend that existing decontamination procedures for tall structures be re-examined …
Date: November 17, 2009
Creator: Farfan, E.
System: The UNT Digital Library
Modeling daily flow patterns individuals to characterize disease spread (open access)

Modeling daily flow patterns individuals to characterize disease spread

The effect of an individual's travels throughout a day on the spread of disease is examined using a deterministic SIR model. We determine which spatial and demographic characteristics most contribute to the disease spread and whether the progression of the disease can be slowed by appropriate vaccination of people belonging to a specific location-type.
Date: November 17, 2002
Creator: Smallwood, J. (Jeanine); Hyman, J. M. (James M.) & Mirchandani, Pitu B.
System: The UNT Digital Library
The dissociation of liquid silica at high pressure and temperature (open access)

The dissociation of liquid silica at high pressure and temperature

Liquid silica at high pressure and temperature is shown to undergo significant structural modifications and profound changes in its electronic properties. Temperature measurements on shock waves in silica at 70-1000 GPa indicate that the specific heat of liquid SiO{sub 2} rises well above the Dulong-Petit limit, exhibiting a broad peak with temperature that is attributable to the growing structural disorder caused by bond-breaking in the melt. The simultaneous sharp rise in optical reflectivity of liquid SiO{sub 2} indicates that dissociation causes the electrical and therefore thermal conductivities of silica to attain metallic-like values of 1-5 x 10{sup 5} S/m and 24-600 W/m.K respectively.
Date: November 17, 2005
Creator: Hicks, D.; Boehly, T.; Eggert, J.; Miller, J.; Celliers, P. & Collins, G.
System: The UNT Digital Library
POSTCLOSURE GROUNDWATER REMEDIATION AND MONITORING AT THE SANITARY LANDFILL, SAVANNAH RIVER SITE TRANSITIONING TO MONITORED NATURAL ATTENUATION (open access)

POSTCLOSURE GROUNDWATER REMEDIATION AND MONITORING AT THE SANITARY LANDFILL, SAVANNAH RIVER SITE TRANSITIONING TO MONITORED NATURAL ATTENUATION

Resource Conservation and Recovery Act (RCRA) requirements for hazardous waste facilities include 30 years of post-closure monitoring. The use of an objective-based monitoring strategy allows for a significant reduction in the amount of groundwater monitoring required, as the groundwater remediation transitions from an active biosparging system to monitored natural attenuation. The lifecycle of groundwater activities at the landfill has progressed from detection monitoring and plume characterization, to active groundwater remediation, and now to monitored natural attenuation and postclosure monitoring. Thus, the objectives of the groundwater monitoring have changed accordingly. Characterization monitoring evaluated what biogeochemical natural attenuation processes were occurring and determined that elevated levels of radium were naturally occurring. Process monitoring of the biosparging system required comprehensive sampling network up- and down-gradient of the horizontal wells to verify its effectiveness. Currently, the scope of monitoring and reporting can be significantly reduced as the objective is to demonstrate that the alternate concentration limits (ACL) are being met at the point of compliance wells and the maximum contaminant level (MCL) is being met at the surface water point of exposure. The proposed reduction is estimated to save about $2M over the course of the remaining 25 years of postclosure monitoring.
Date: November 17, 2006
Creator: Ross, J; Walt Kubilius, W; Thomas Kmetz, T; D Noffsinger, D & Karen M Adams, K
System: The UNT Digital Library
Phase stability in heavy f-electron metals from first-principles theory (open access)

Phase stability in heavy f-electron metals from first-principles theory

The structural phase stability of heavy f-electron metals is studied by means of density-functional theory (DFT). These include temperature-induced transitions in plutonium metal as well as pressure-induced transitions in the trans-plutonium metals Am, Cm, Bk, and Cf. The early actinides (Th-Np) display phases that could be rather well understood from the competition of a crystal-symmetry breaking mechanism (Peierls distortion) of the 5f states and electrostatic forces, while for the trans-plutonium metals (Am-Cf) the ground-state structures are governed by 6d bonding. We show in this paper that new physics is needed to understand the phases of the actinides in the volume range of about 15-30 {angstrom}{sup 3}. At these volumes one would expect, from theoretical arguments made in the past, to encounter highly complex crystal phases due to a Peierls distortion. Here we argue that the symmetry reduction associated with spin polarization can make higher symmetry phases competitive. Taking this into account, DFT is shown to describe the well-known phase diagram of plutonium and also the recently discovered complex and intriguing high-pressure phase diagrams of Am and Cm. The theory is further applied to investigate the behaviors of Bk and Cf under compression.
Date: November 17, 2005
Creator: Soderlind, P
System: The UNT Digital Library
Observation of the Exclusive Reaction e^+e^-\ to \phi\eta at \sqrt{s}=10.58 GeV (open access)

Observation of the Exclusive Reaction e^+e^-\ to \phi\eta at \sqrt{s}=10.58 GeV

The authors report the observation of e{sup +}e{sup -} {yields} {phi}{eta} near {radical}s = 10.58 GeV with 6.5 {sigma} significance in the K{sup +}K{sup -}{gamma}{gamma} final state in a data sample of 224 fb{sup -1} collected by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage rings. They measure the restricted radiation-corrected cross section to be {sigma}(e{sup +}e{sup -} {yields} {phi}{eta}) = 2.1 {+-} 0.4(stat) {+-} 0.1(syst) fb within the range |cos{theta}*| < 0.8, where {theta}* is the center-of-mass polar angle of the {phi} meson. The {phi} meson is required to be in the invariant mass range of 1.008 < m{sub {phi}} < 1.035 GeV/c{sup 2}. The radiation corrected cross section in the full cos {theta}* range is extrapolated to be 2.9 {+-} 0.5(stat) {+-} 0.1(syst) fb.
Date: November 17, 2006
Creator: Aubert, B.
System: The UNT Digital Library
Hybrid atomic models for spectroscopic plasma diagnostics (open access)

Hybrid atomic models for spectroscopic plasma diagnostics

We propose a hybrid approach to treating atomic structure and rates in collisional-radiative models, combining the completeness of highly averaged models with the accuracy of detailed models. The hybrid scheme supplements a small subset of coronally accessible fine structure levels with a complete set of configuration- and superconfiguration-averaged levels and produces spectra based on transitions among a mix of fine-structure and relativistic configuration-averaged levels. Convenient expressions are given for obtaining rates between the fine structure and averaged levels and a technique for propagating configuration interaction from the fine structure calculations to configuration averages is described. We present results from a trial hybrid model of germanium which demonstrate the accuracy of the hybrid model for charge state distributions and spectra.
Date: November 17, 2006
Creator: Hansen, S B; Bauche, J; Bauche-Arnoult, C & Gu, M F
System: The UNT Digital Library
A Novel 14C-Postlabeling Assay Using Accelerator Mass Spectrometry For the Detection of O6-Methyldeoxyguanosine Adducts (open access)

A Novel 14C-Postlabeling Assay Using Accelerator Mass Spectrometry For the Detection of O6-Methyldeoxyguanosine Adducts

Accelerator mass spectrometry (AMS) is currently one of the most sensitive methods available for the trace detection of DNA adducts and is particularly valuable for measuring adducts in humans or animal models. However, the standard approach requires administration of a radiolabeled compound. As an alternative, we have developed a preliminary {sup 14}C-postlabeling assay for detection of the highly mutagenic O{sup 6}-MedG, by AMS. Procedures were developed for derivatizing O{sup 6}-MedG using unlabeled acetic anhydride. Using conventional LC-MS analysis, the limit of detection for the major product, triacetylated O{sup 6}-MedG, was 10 fmoles. On reaction with {sup 14}C-acetic anhydride, using a specially designed enclosed system, the predominant product was {sup 14}C-di-acetyl O{sup 6}-MedG. This change in reaction profile was due to a modification of the reaction procedure, introduced as a necessary safety precaution. The limit of detection for {sup 14}C-diacetyl O{sup 6}-MedG by AMS was determined as 79 attomoles, {approx}18,000 fold lower than that achievable by LSC. Although the assay has so far only been carried out with labeled standards, the degree of sensitivity obtained illustrates the potential of this assay for measuring O{sup 6}-MedG levels in humans.
Date: November 17, 2005
Creator: Thompkins, E. M.; Farmer, P. B.; Lamb, J. H.; Jukes, R.; Dingley, K.; Ubick, E. A. et al.
System: The UNT Digital Library
Evidence for the Rare Decay B+ to Ds+ pi0 (open access)

Evidence for the Rare Decay B+ to Ds+ pi0

The authors have searched for the rare decay B{sup +} {yields} D{sub s}{sup +}{pi}{sup 0}. The analysis is based on a sample of 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. They find 19.6 signal events, corresponding to a significance of 4.7 {sigma}. The extracted signal yield including statistical and systematic uncertainties is 20.1{sub -6.0-1.5}{sup +6.8+0.4}, and they measure {Beta}(B{sup +} {yields} D{sub s}{sup +}{pi}{sup 0}) = (1.5{sub -0.4}{sup +0.5} {+-} 0.1 {+-} 0.2) x 10{sup -5}, where the first uncertainty is statistical, the second is systematic, and the last is due to the uncertainty on the D{sub s}{sup +} decay and its daughter decay branching fractions.
Date: November 17, 2006
Creator: Aubert, B.
System: The UNT Digital Library
Spectral Predictors (open access)

Spectral Predictors

Many scientific, imaging, and geospatial applications produce large high-precision scalar fields sampled on a regular grid. Lossless compression of such data is commonly done using predictive coding, in which weighted combinations of previously coded samples known to both encoder and decoder are used to predict subsequent nearby samples. In hierarchical, incremental, or selective transmission, the spatial pattern of the known neighbors is often irregular and varies from one sample to the next, which precludes prediction based on a single stencil and fixed set of weights. To handle such situations and make the best use of available neighboring samples, we propose a local spectral predictor that offers optimal prediction by tailoring the weights to each configuration of known nearby samples. These weights may be precomputed and stored in a small lookup table. We show that predictive coding using our spectral predictor improves compression for various sources of high-precision data.
Date: November 17, 2006
Creator: Ibarria, L; Lindstrom, P & Rossignac, J
System: The UNT Digital Library
Metabolic analysis of the soil microbe Dechloromonas aromatica str. RCB: indications of a surprisingly complex life-style and cryptic anaerobic pathways for aromatic degradation (open access)

Metabolic analysis of the soil microbe Dechloromonas aromatica str. RCB: indications of a surprisingly complex life-style and cryptic anaerobic pathways for aromatic degradation

Initial interest in Dechloromonas aromatica strain RCB arose from its ability to anaerobically degrade benzene. It is also able to reduce perchlorate and oxidize chlorobenzoate, toluene, and xylene, creating interest in using this organism for bioremediation. Little physiological data has been published for this microbe. It is considered to be a free-living organism. The a priori prediction that the D. aromatica genome would contain previously characterized 'central' enzymes involved in anaerobic aromatic degradation proved to be false, suggesting the presence of novel anaerobic aromatic degradation pathways in this species. These missing pathways include the benzyl succinyl synthase (bssABC) genes (responsible for formate addition to toluene) and the central benzoylCoA pathway for monoaromatics. In depth analyses using existing TIGRfam, COG, and InterPro models, and the creation of de novo HMM models, indicate a highly complex lifestyle with a large number of environmental sensors and signaling pathways, including a relatively large number of GGDEF domain signal receptors and multiple quorum sensors. A number of proteins indicate interactions with an as yet unknown host, as indicated by the presence of predicted cell host remodeling enzymes, effector enzymes, hemolysin-like proteins, adhesins, NO reductase, and both type III and type VI secretory complexes. Evidence of …
Date: November 17, 2008
Creator: Salinero, Kennan Kellaris; Keller, Keith; Feil, William S.; Feil, Helene; Trong, Stephan; Di Bartolo, Genevieve et al.
System: The UNT Digital Library
Lack of Support for the Association Between GAD2 Polymorphisms and Severe Human Obesity (open access)

Lack of Support for the Association Between GAD2 Polymorphisms and Severe Human Obesity

Demonstration of association between common genetic variants and chronic human diseases such as obesity could have profound implications for the prediction, prevention and treatment of these conditions. Unequivocal proof of such an association, however, requires adherence to established methodological guidelines, which include independent replication of initial positive findings. Recently, single nucleotide polymorphisms (SNPs) within GAD2 were found to be associated with class III obesity (BMI > 40 kg/m2) in 188 families (612 individuals) segregating the condition and a case-control study of 575 cases and 646 lean controls. Functional data supporting a pathophysiological role for one of the SNPs (-243A>G) were also presented. In the present study, we attempted to replicate this association in larger groups of subjects, and to extend the functional studies of the -243A>G SNP. In 2,327 subjects comprising 692 German nuclear families with severe, early-onset obesity, we found no evidence for a relationship between the three GAD2 SNPs and obesity, whether SNPs were studied individually or as haplotypes. In two independent case-control studies (a total of 680 class III obesity cases and 1,186 lean controls), there was no significant relationship between the -243A>G SNP and obesity (odds ratio (OR) = 0.99, 95% CI 0.83 - 1.18,in the …
Date: November 17, 2004
Creator: Swarbrick, Michael M.; Waldenmaier, Bjorn; Pennacchio, Len A.; Lind,Denise L.; Cavazos, Martha M.; Geller, Frank et al.
System: The UNT Digital Library
Engineering Monosodium Titanate for Adsorption Column Processes (open access)

Engineering Monosodium Titanate for Adsorption Column Processes

Monosodium titanate (MST) is an inorganic adsorbent powder that effectively removes strontium, plutonium, neptunium, and other trace elements from alkaline high-level waste (HLW) supernate. This work tested one commercial titanate and four general methods to engineer MST into particles large enough to use in adsorption columns. The most successful of the engineered products selected from batch contact and chemical stability testing succeeded in treating 2900 bed volumes (BV) of simulated salt waste containing dissolved plutonium and strontium. There was no detectable strontium breakthrough and only 6 per cent plutonium breakthrough--well within the processing goal--at the end of the demonstration which operated at 5.3 BV/hour. Additional column tests at nominally 15 BV/hr demonstrated similar removal performance. Batch testing of adsorbents used both actual Savannah River Site (SRS) tank supernate as well as simulated salt solutions spiked with strontium, neptunium, and plutonium. In tank waste tests, internal gelation beads produced by the Oak Ridge National Laboratory (ORNL) demonstrated a batch distribution coefficient of 35,000 +/- 4,000 mL/g for plutonium at a phase ratio of 1970 mL/g. In the same batch the sorbent demonstrated a batch distribution coefficient of 99,000 +/- 7,500 mL/g for strontium. These results indicate that this material should be …
Date: November 17, 2004
Creator: NASH, CHARLES
System: The UNT Digital Library
Investigation of alternative materials for impregnation of Nb3Sn accelerator magnets (open access)

Investigation of alternative materials for impregnation of Nb3Sn accelerator magnets

Insulation is one of the most important elements of magnet design, which determines the electrical, mechanical, and thermal performance as well as lifetime of the magnet. The exposure to high radiation loads especially for the proposed LHC second-generation interaction region Nb{sub 3}Sn quadrupoles further limits the choices of the insulation materials. Traditionally Nb{sub 3}Sn magnets were impregnated with epoxy to improve both the mechanical and electrical properties. However, the acceptable radiation limit for epoxy is low which reduces the lifetime of the magnet. The paper presents the results of the feasibility study to replace epoxy with high radiation-resistant material during vacuum impregnation. The mechanical, thermal and electrical properties of samples impregnated with Matrimid were measured and compared with epoxy-impregnated samples.
Date: November 17, 2003
Creator: Deepak Reddy Chichili, Jay Hoffman and Alexander Zlobin
System: The UNT Digital Library
Risk Informing the Nuclear Materials and Waste Arenas. (open access)

Risk Informing the Nuclear Materials and Waste Arenas.

None
Date: November 17, 2002
Creator: Bari, R. A.; Mubayi, V.; Azarm, M. A.; Grove, E. J.; Xu, J.; Bailey, M. G. et al.
System: The UNT Digital Library
Complete Photo-Induced Breakup of the H2 Molecule as a Probe ofMolecular Electron Correlation (open access)

Complete Photo-Induced Breakup of the H2 Molecule as a Probe ofMolecular Electron Correlation

Despite decades of progress in quantum mechanics, electron correlation effects are still only partially understood. Experiments in which both electrons are ejected from an oriented hydrogen molecule by absorption of a single photon have recently demonstrated a puzzling phenomenon: The ejection pattern of the electrons depends sensitively on the bond distance between the two nuclei as they vibrate in their ground state. Here we report a complete numerical solution of the Schrodinger equation for the double photoionization of H2. The results suggest that the distribution of photoelectrons emitted from aligned molecules reflects electron correlation effects that are purely molecular in origin.
Date: November 17, 2005
Creator: Vanroose, Wim; Martin, Fernando; Rescigno, Thomas N. & McCurdy, C. William
System: The UNT Digital Library