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PHASE II VAULT TESTING OF THE ARGONNE RFID SYSTEM (open access)

PHASE II VAULT TESTING OF THE ARGONNE RFID SYSTEM

The U.S. Department of Energy (DOE) (Environmental Management [EM], Office of Packaging and Transportation [EM-45]) Packaging and Certification Program (DOE PCP) has developed a Radio Frequency Identification (RFID) tracking and monitoring system, called ARG-US, for the management of nuclear materials packages during transportation and storage. The performance of the ARG-US RFID equipment and system has been fully tested in two demonstration projects in April 2008 and August 2009. With the strong support of DOE-SR and DOE PCP, a field testing program was completed in Savannah River Site's K-Area Material Storage (KAMS) Facility, an active Category I Plutonium Storage Facility, in 2010. As the next step (Phase II) of continued vault testing for the ARG-US system, the Savannah River Site K Area Material Storage facility has placed the ARG-US RFIDs into the 910B storage vault for operational testing. This latest version (Mark III) of the Argonne RFID system now has the capability to measure radiation dose and dose rate. This paper will report field testing progress of the ARG-US RFID equipment in KAMS, the operability and reliability trend results associated with the applications of the system, and discuss the potential benefits in enhancing safety, security and materials accountability. The purpose of …
Date: June 25, 2012
Creator: Willoner, T.; Turlington, R. & Koenig, R.
System: The UNT Digital Library
SINGLE-SHELL TANKS LEAK INTEGRITY ELEMENTS/SX FARM LEAK CAUSES AND LOCATIONS - 12127 (open access)

SINGLE-SHELL TANKS LEAK INTEGRITY ELEMENTS/SX FARM LEAK CAUSES AND LOCATIONS - 12127

Washington River Protection Solutions, LLC (WRPS) developed an enhanced single-shell tank (SST) integrity project in 2009. An expert panel on SST integrity was created to provide recommendations supporting the development of the project. One primary recommendation was to expand the leak assessment reports (substitute report or LD-1) to include leak causes and locations. The recommendation has been included in the M-045-9IF Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) as one of four targets relating to SST leak integrity. The 241-SX Farm (SX Farm) tanks with leak losses were addressed on an individual tank basis as part of LD-1. Currently, 8 out of 23 SSTs that have been reported to having a liner leak are located in SX Farm. This percentage was the highest compared to other tank farms which is why SX Farm was analyzed first. The SX Farm is comprised of fifteen SSTs built 1953-1954. The tanks are arranged in rows of three tanks each, forming a cascade. Each of the SX Farm tanks has a nominal I-million-gal storage capacity. Of the fifteen tanks in SX Farm, an assessment reported leak losses for the following tanks: 241-SX-107, 241-SX-108, 241-SX-109, 241-SX-111, 241-SX-112, 241-SX-113, 241-SX-114 and 241-SX-115. The method …
Date: January 25, 2012
Creator: TJ, VENETZ; D, WASHENFELDER; J, JOHNSON & C, GIRARDOT
System: The UNT Digital Library
Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice (open access)

Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice

It has been proposed to implement the so-called Achromatic Telescopic Squeezing (ATS) scheme in the LHC high luminosity (HL) lattice to reduce beta functions at the Interaction Points (IP) up to a factor of 8. As a result, the nominal 4.5 km peak beta functions reached in the Inner Triplets (IT) at collision will be increased by the same factor. This, therefore, justifies the installation of new, larger aperture, superconducting IT quadrupoles. The higher beta functions will enhance the effects of the triplet quadrupole field errors leading to smaller beam dynamic aperture (DA). To maintain the acceptable DA, the effects of the triplet field errors must be re-evaluated, thus specifying new tolerances. Such a study has been performed for the so-called '4444' collision option of the HL-LHC layout version SLHCV3.01, where the IP beta functions are reduced by a factor of 4 in both planes with respect to a pre-squeezed value of 60 cm at two collision points. The dynamic aperture calculations were performed using SixTrack. The impact on the triplet field quality is presented.
Date: June 25, 2012
Creator: Nosochkov, Yuri; Cai, Y.; Jiao, Y.; Wang, M. H.; Fartoukh, S.; Giovannozzi, M. et al.
System: The UNT Digital Library
Surface Engineering of Corrosion, Environmental Fracture, Cavitation & Impingement Resistant Materials (open access)

Surface Engineering of Corrosion, Environmental Fracture, Cavitation & Impingement Resistant Materials

None
Date: July 25, 2012
Creator: Farmer, J; Rukbenchik, A; Menon, S; McNelley, T & Hackel, L
System: The UNT Digital Library
Status of High Power Tests of Normal Conducting Single-Cell Standing Wave Structures (open access)

Status of High Power Tests of Normal Conducting Single-Cell Standing Wave Structures

Our experiments are directed toward the understanding of the physics of rf breakdown in systems that can be used to accelerate electron beams at {approx}11.4 GHz. The structure geometries have apertures, stored energy per cell, and rf pulse duration close to that of the NLC or CLIC. The breakdown rate is the main parameter that we use to compare rf breakdown behavior for different structures at a given set of rf pulse parameters (pulse shape and peak power) at 60 Hz repetition rate. In our experiments, the typical range of the breakdown rate is from one per few hours to {approx}100 per hour. To date we have tested 29 structures. We consistently found that after the initial conditioning, the behavior of the breakdown rate is reproducible for structures of the same geometry and material, and the breakdown rate dependence on peak magnetic fields is stronger than on peak surface electric fields for structures of different geometries. Below we report the main results from tests of seven structures made from hard copper, soft copper alloys and hard-copper alloys. Additional details on these and other structures will be discussed in future publications.
Date: June 25, 2012
Creator: Dolgashev, Valery; Tantawi, Sami; Yeremian, Anahid; Higashi, Yasuo & Spataro, Bruno
System: The UNT Digital Library
High-harmonic Fast Wave Heating and Current Drive Results for Deuterium H-mode Plasmas in the National Spherical Torus Experiment (open access)

High-harmonic Fast Wave Heating and Current Drive Results for Deuterium H-mode Plasmas in the National Spherical Torus Experiment

A critical research goal for the spherical torus (ST) program is to initiate, ramp-up, and sustain a discharge without using the central solenoid. Simulations of non-solenoidal plasma scenarios in the National Spherical Torus Experiment (NSTX) [1] predict that high-harmonic fast wave (HHFW) heating and current drive (CD) [2] can play an important roll in enabling fully non-inductive (fNI {approx} 1) ST operation. The NSTX fNI {approx} 1 strategy requires 5-6 MW of HHFW power (PRF) to be coupled into a non-inductively generated discharge [3] with a plasma current, Ip {approx} 250-350 kA, driving the plasma into an HHFW H-mode with Ip {approx} 500 kA, a level where 90 keV deuterium neutral beam injection (NBI) can heat the plasma and provide additional CD. The initial approach on NSTX has been to heat Ip {approx} 300 kA, inductively heated, deuterium plasmas with CD phased HHFW power [2], in order to drive the plasma into an H-mode with fNI {approx} 1.
Date: July 25, 2012
Creator: Taylor, G.; Bonoli, P. T.; Harvey, R. W.; Hosea, J. C.; Jaeger, E. F.; LeBlanc, B. P. et al.
System: The UNT Digital Library
Ionization of Water Clusters is Mediated by Exciton Energy Transfer from Argon Clusters (open access)

Ionization of Water Clusters is Mediated by Exciton Energy Transfer from Argon Clusters

The exciton energy deposited in an argon cluster, (Arn ,< n=20>) using VUV radiation is transferred to softly ionize doped water clusters, ((H2O)n, n=1-9) leading to the formation of non-fragmented clusters. Following the initial excitation, electronic energy is channeled to ionize the doped water cluster while evaporating the Ar shell, allowing identification of fragmented and complete water cluster ions. Examination of the photoionization efficiency curve shows that cluster evaporation from excitons located above 12.6 eV are not enough to cool the energized water cluster ion, and leads to their dissociation to (H2O)n-2H+ (protonated) clusters.
Date: January 25, 2012
Creator: Golan, Amir & Ahmed, Musahid
System: The UNT Digital Library
HOM identification by bead pulling in the Brookhaven ERL cavity (open access)

HOM identification by bead pulling in the Brookhaven ERL cavity

Several past measurements of the Brookhaven ERL at superconducting temperature produced a long list of higher order modes (HOMs). The Niobium 5-cell cavity is terminated with HOM ferrite dampers that successfully reduce the Q-factors to tolerable levels. However, a number of undamped resonances with Q {ge} 10{sup 6} were found at 4 K and their mode identification remained as a goal for this paper. The approach taken here consists in taking different S{sub 21} measurements on a copper cavity replica of the ERL which can be compared with the actual data and also with Microwave Studio computer simulations. Several different S{sub 21} transmission measurements are used, including those taken from the fundamental input coupler to the pick-up probe across the cavity, between probes in a single cell, and between beam-position monitor probes in the beam tubes. Mode identification is supported by bead pulling with a metallic needle or a dielectric sphere that are calibrated in the fundamental mode. This paper presents results for HOMs in the first two dipole bands with the prototypical 958 MHz trapped mode, the lowest beam tube resonances, and high-Q modes in the first quadrupole band and beyond.
Date: June 25, 2012
Creator: Hahn, H.; Calaga, R.; Jain, P.; Johnson, E. C. & Xu, W.
System: The UNT Digital Library
Scattering in Thin Foils Associated with Passive Proton and Ion Beam Focusing (open access)

Scattering in Thin Foils Associated with Passive Proton and Ion Beam Focusing

None
Date: October 25, 2012
Creator: Yuen, A; Lund, S M; Barnard, J J & Cohen, R H
System: The UNT Digital Library
The Six-Point Remainder Function to all Loop Orders in the Multi-Regge Limit (open access)

The Six-Point Remainder Function to all Loop Orders in the Multi-Regge Limit

None
Date: September 25, 2012
Creator: Pennington, Jeffrey
System: The UNT Digital Library
End-To-End Solution for Integrated Workload and Data Management Using Glidein WMS and Globus Online (open access)

End-To-End Solution for Integrated Workload and Data Management Using Glidein WMS and Globus Online

None
Date: June 25, 2012
Creator: Mhashilkar, Parag; Garzoglio, Gabriele; Holzman, Burt; Duan, Xi; /Fermilab; Miller, Zachary et al.
System: The UNT Digital Library
Searches for Leptonic B Decays at BaBar (open access)

Searches for Leptonic B Decays at BaBar

Measurements of the branching fractions of purely leptonic decays of B-mesons translate into constraints in the plane of the charged Higgs mass versus tan {beta} which are relatively insensitive to the particular theoretical model. Using the full BABAR dataset of 450 million B-decays we search for these decays. No significant signal is found in the decays into electrons or muons and we set upper limits on the branching fractions of the order of a 10{sup -6} at 90% confidence level. We measure the branching fraction of B {yields} {tau}{mu} to be (1.7 {+-} 0.6) x 10{sup -4}.
Date: April 25, 2012
Creator: Nelson, Silke
System: The UNT Digital Library
Progress in Studies of Electron-Cloud-Induced Optics Distortions at CesrTA (open access)

Progress in Studies of Electron-Cloud-Induced Optics Distortions at CesrTA

The Cornell Electron Storage Ring Test Accelerator (CesrTA) program has included extensive measurements of coherent betatron tune shifts for a variety of electron and positron beam energies, bunch population levels, and bunch train configurations. The tune shifts have been shown to result primarily from the interaction of the beam with the space-charge field of the beam-induced low-energy electron cloud in the vacuum chamber. Comparison to several advanced electron cloud simulation codes has allowed determination of the sensitivity of these measurements to physical parameters characterizing the synchrotron radiation flux, the production of photo-electrons on the vacuum chamber wall, the beam emittance, lattice optics, and the secondary-electron yield model. We report on progress in understanding the cloud buildup and decay mechanisms in magnetic fields and in field-free regions, addressing quantitatively the precise determination of the physical parameters of the modeling. Validation of these models will serve as essential input in the design of damping rings for future high-energy linear colliders.
Date: June 25, 2012
Creator: Crittenden, James; /Cornell U., CLASSE; Calvey, Joseph; /Cornell U., CLASSE; Dugan, Gerald; /Cornell U., CLASSE et al.
System: The UNT Digital Library
Oxy-Combustion Environment Characterization: Fire- and Steam-Side Corrosion in Advanced Combustion (open access)

Oxy-Combustion Environment Characterization: Fire- and Steam-Side Corrosion in Advanced Combustion

Oxy-fuel combustion is burning a fuel in oxygen rather than air. The low nitrogen flue gas that results is relatively easy to capture CO{sub 2} from for reuse or sequestration. Corrosion issues associated with the environment change (replacement of much of the N{sub 2} with CO{sub 2} and higher sulfur levels) from air- to oxy-firing were examined. Alloys studied included model Fe-Cr alloys and commercial ferritic steels, austenitic steels, and nickel base superalloys. The corrosion behavior is described in terms of corrosion rates, scale morphologies, and scale/ash interactions for the different environmental conditions. Additionally, the progress towards laboratory oxidation tests in advanced ultra-supercritical steam is updated.
Date: September 25, 2012
Creator: Holcomb, G. R.; Tylczak, J.; Meier, G. H.; Lutz, B. S.; Yanar, N. M.; Pettit, F. S. et al.
System: The UNT Digital Library
Study of the e+ e- to Hadrons Via ISR at BaBar (open access)

Study of the e+ e- to Hadrons Via ISR at BaBar

None
Date: September 25, 2012
Creator: Solodov, E. P.
System: The UNT Digital Library
Polarization Analysis for Seeded FELs in a Crossed-Planar Undulator (open access)

Polarization Analysis for Seeded FELs in a Crossed-Planar Undulator

The crossed-planar undulator is a promising scheme for full polarization control in x-ray FELs. For SASE FELs, it has been shown a maximum degree of circular polarization of about 80% is achievable at fundamental wavelength just before saturation. In this paper, we study the effectiveness of a crossed undulator for a seeded x-ray FEL. The degree of circular polarization for both the fundamental and the harmonic radiation are considered. Simulations with realistic beam distributions show that a degree of circular polarization of over 90% and 80% is obtainable at the fundamental and 2nd harmonic frequencies, respectively.
Date: June 25, 2012
Creator: Geng, Huiping; /SLAC; Ding, Yuantao; /SLAC; Huang, Zhirong; /SLAC et al.
System: The UNT Digital Library
Calculation of Eddy Currents In the CTH Vacuum Vessel and Coil Frame (open access)

Calculation of Eddy Currents In the CTH Vacuum Vessel and Coil Frame

Knowledge of eddy currents in the vacuum vessel walls and nearby conducting support structures can significantly contribute to the accuracy of Magnetohydrodynamics (MHD) equilibrium reconstruction in toroidal plasmas. Moreover, the magnetic fields produced by the eddy currents could generate error fields that may give rise to islands at rational surfaces or cause field lines to become chaotic. In the Compact Toroidal Hybrid (CTH) device (R0 = 0.75 m, a = 0.29 m, B ≤ 0.7 T), the primary driver of the eddy currents during the plasma discharge is the changing flux of the ohmic heating transformer. Electromagnetic simulations are used to calculate eddy current paths and profile in the vacuum vessel and in the coil frame pieces with known time dependent currents in the ohmic heating coils. MAXWELL and SPARK codes were used for the Electromagnetic modeling and simulation. MAXWELL code was used for detailed 3D finite-element analysis of the eddy currents in the structures. SPARK code was used to calculate the eddy currents in the structures as modeled with shell/surface elements, with each element representing a current loop. In both cases current filaments representing the eddy currents were prepared for input into VMEC code for MHD equilibrium reconstruction of …
Date: September 25, 2012
Creator: Zolfaghari, A.; Brooks, A; Michaels, A.; Hanson, J. & Hartwell, G.
System: The UNT Digital Library
Recent Bottomonium Results from BaBar and Belle (open access)

Recent Bottomonium Results from BaBar and Belle

Selected studies in bottomonium physics carried out by the BaBar and Belle experiments are presented. They include a study of radiative bottomonium transitions using {gamma} {yields} e{sup +}e{sup -} conversions done by BaBar, the search for the h{sub b}(1P) and h{sub b}(2P) states leading to an evidence for the h{sub b}(1P) seen by BaBar in {Upsilon}(3S) {yields} {pi}{sup 0} h{sub b} decay and to the Belle observation of both the h{sub b}(1P) and the h{sub b}(2P) in the reaction e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -} h{sub b}(1P,2P) from {Upsilon}(5S) data.
Date: June 25, 2012
Creator: Ziegler, Veronique
System: The UNT Digital Library
A Summary of Taxonomies of Digital System Failure Modes Provided by the DigRel Task Group (open access)

A Summary of Taxonomies of Digital System Failure Modes Provided by the DigRel Task Group

Recently, the CSNI directed WGRisk to set up a task group called DIGREL to initiate a new task on developing a taxonomy of failure modes of digital components for the purposes of PSA. It is an important step towards standardized digital I&C reliability assessment techniques for PSA. The objective of this paper is to provide a comparison of the failure mode taxonomies provided by the participants. The failure modes are classified in terms of their levels of detail. Software and hardware failure modes are discussed separately.
Date: June 25, 2012
Creator: L., Chu T.; M., Yue & Postma, W.
System: The UNT Digital Library
Collective Effects in the SuperB Collider (open access)

Collective Effects in the SuperB Collider

Some collective effects have been studied for the SuperB high luminosity collider. Estimates of the effect of Intra Beam Scattering (IBS) on the emittance and energy spread growths have been carried up for both the High Energy (HER, positrons) and the Low Energy (LER, electrons) rings. Electron cloud build up simulations for HER were performed with the ECLOUD code, developed at CERN, to predict the cloud formation in the arcs, taking into account possible remediation techniques such as clearing electrodes. The new code CMAD, developed at SLAC, has been used to study the effect of this electron cloud on the beam and assess the thresholds above which the electron cloud instability would set in.
Date: June 25, 2012
Creator: Demma, Theo; /INFN, Rome & Pivi, Mauro
System: The UNT Digital Library
Simulations of Ion Migration in the LCLS RF Gun and Injector (open access)

Simulations of Ion Migration in the LCLS RF Gun and Injector

The motivation for this work was the observed surface contamination of the first LCLS RF gun copper cathode. We will present the results of simulations in regards to ion migration in the LCLS gun. Ions of residual gases will be created by interaction of molecular gas species with the UV drive laser beam and by the electron beam itself. The larger part of those ionized molecules remain in the vicinity of creation, are transported towards beam line walls or away from the cathode. However a small fraction gains enough kinetic energy, focused by RF and magnetic fields and propagates to the cathode, producing an undesirable increase of the cathode's surface work function. Although this fraction is small, during long term operation, this effect may become a significant factor limiting the source performance.
Date: June 25, 2012
Creator: Brachmann, Axel & Dowell, David
System: The UNT Digital Library
2012 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 20-25, 2012 (open access)

2012 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 20-25, 2012

The Gordon Research Conference on MICROBIAL STRESS RESPONSE was held at Mount Holyoke College, South Hadley, Massachusetts, July 15-20, 2012. The Conference was well-attended with 180 participants. The 2012 Microbial Stress Responses Gordon Research Conference will provide a forum for the open reporting of recent discoveries on the diverse mechanisms employed by microbes to respond to stress. Approaches range from analysis at the molecular level (how are signals perceived and transmitted to change gene expression or function) to cellular and microbial community responses. Gordon Research Conferences does not permit publication of meeting proceedings.
Date: July 25, 2012
Creator: Donohue, Timothy
System: The UNT Digital Library
Contemporary Fraction of bis(2-ethylhexyl) Phthalate in Stilton Cheese by Accelerator Mass Spectrometry (open access)

Contemporary Fraction of bis(2-ethylhexyl) Phthalate in Stilton Cheese by Accelerator Mass Spectrometry

None
Date: September 25, 2012
Creator: Nelson, M. A.; Ondov, J. A.; VanDerveer, M. C. & Buchholz, B. A.
System: The UNT Digital Library
Markov Model of Severe Accident Progression and Management (open access)

Markov Model of Severe Accident Progression and Management

The earthquake and tsunami that hit the nuclear power plants at the Fukushima Daiichi site in March 2011 led to extensive fuel damage, including possible fuel melting, slumping, and relocation at the affected reactors. A so-called feed-and-bleed mode of reactor cooling was initially established to remove decay heat. The plan was to eventually switch over to a recirculation cooling system. Failure of feed and bleed was a possibility during the interim period. Furthermore, even if recirculation was established, there was a possibility of its subsequent failure. Decay heat has to be sufficiently removed to prevent further core degradation. To understand the possible evolution of the accident conditions and to have a tool for potential future hypothetical evaluations of accidents at other nuclear facilities, a Markov model of the state of the reactors was constructed in the immediate aftermath of the accident and was executed under different assumptions of potential future challenges. This work was performed at the request of the U.S. Department of Energy to explore 'what-if' scenarios in the immediate aftermath of the accident. The work began in mid-March and continued until mid-May 2011. The analysis had the following goals: (1) To provide an overall framework for describing possible …
Date: June 25, 2012
Creator: Bari, R. A.; Cheng, L.; Cuadra, A.; Ginsberg, T.; Lehner, J.; Martinez-Guridi, G. et al.
System: The UNT Digital Library