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Rare B Decays at Babar (open access)

Rare B Decays at Babar

The author presents some of the most recent BABAR measurements for rare B decays. These include rate asymmetries in the B decays to K{sup (*)}l{sup +}l{sup -} and K{sup +}{pi}{sup -} and branching fractions in the B decays to l{sup +}{nu}{sub l}, K{sub 1}(1270){sup +}{pi}{sup -} and K{sub 1}(1400){sup +}{pi}{sup -}. The author also reports a search for the B{sup +} decay to K{sub S}{sup 0}K{sub S}{sup 0}{pi}{sup +}.
Date: January 12, 2009
Creator: Palombo, Fernando & Collaboration, for the BABAR
System: The UNT Digital Library
Measurement of Time-Dependent CP Asymmetry in B0->ccbar K(*)0 Decays (open access)

Measurement of Time-Dependent CP Asymmetry in B0->ccbar K(*)0 Decays

The authors present updated measurements of time-dependent Cp asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465 {+-} 5) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} storage rings operating at the SLAC National Accelerator Laboratory. The time-dependent CP asymmetry parameters measured from J/{psi} K{sub S}{sup 0}, J/{psi}K{sub L}{sup 0}, {psi}(2S)K{sub S}{sup 0}, {eta}{sub c}K{sub S}{sup 0}, {chi}{sub c1}K{sub S}{sup 0} and J/{psi} K*(892){sup 0} decays are: C{sub f} = 0.024 {+-} 0.020(stat) {+-} 0.016(syst) and -{eta}{sub f}S{sub f} = 0.687 {+-} 0.028(stat) {+-} 0.012(syst).
Date: February 12, 2009
Creator: Aubert, B.
System: The UNT Digital Library
Quantum Calisthenics: Gaussians, The Path Integral and Guided Numerical Approximations (open access)

Quantum Calisthenics: Gaussians, The Path Integral and Guided Numerical Approximations

It is apparent to anyone who thinks about it that, to a large degree, the basic concepts of Newtonian physics are quite intuitive, but quantum mechanics is not. My purpose in this talk is to introduce you to a new, much more intuitive way to understand how quantum mechanics works. I begin with an incredibly easy way to derive the time evolution of a Gaussian wave-packet for the case free and harmonic motion without any need to know the eigenstates of the Hamiltonian. This discussion is completely analytic and I will later use it to relate the solution for the behavior of the Gaussian packet to the Feynman path-integral and stationary phase approximation. It will be clear that using the information about the evolution of the Gaussian in this way goes far beyond what the stationary phase approximation tells us. Next, I introduce the concept of the bucket brigade approach to dealing with problems that cannot be handled totally analytically. This approach combines the intuition obtained in the initial discussion, as well as the intuition obtained from the path-integral, with simple numerical tools. My goal is to show that, for any specific process, there is a simple Hilbert space interpretation …
Date: February 12, 2009
Creator: Weinstein, Marvin
System: The UNT Digital Library
DEMOLISHING A COLD WARE ERA FULE STORAGE BASIN SUPERSTRUCTURE LADEN WITH ASBESTOS (open access)

DEMOLISHING A COLD WARE ERA FULE STORAGE BASIN SUPERSTRUCTURE LADEN WITH ASBESTOS

The K East (KE) Basin facilities are located near the north end of the Hanford Site's 100 K area. The facilities were built in 1950 as part of the KE Reactor complex and constructed within 400 meters of the Columbia River, which is the largest river in the Pacific Northwest and by volume the fourth largest river in the United States. The basin, located adjacent to the reactor, was used for the underwater storage of irradiated nuclear fuel discharged from the reactor. The basin was covered by a superstructure comprising steel columns and beams, concrete, and cement asbestos board (CAB) siding. The project's mission was to complete demolition of the structure over the KE Basin within six months of turnover from facility deactivation activities. The demolition project team applied open-air demolition techniques to bring the facility to slab-on-grade. Several innovative techniques were used to control contamination and maintain contamination control within the confines of the demolition exclusion zone. The techniques, which focused on a defense-in-depth approach, included spraying fixatives on interior and exterior surfaces before demolition began; applying fixatives during the demolition; misting using a fine spray of water during demolition; and demolishing the facility systematically. Another innovative approach that …
Date: January 12, 2009
Creator: ER, LLOYD; JM, STEVENS; EB, DAGAN; TK, ORGILL; MA, GREEN; CH, LARSON et al.
System: The UNT Digital Library
Long-range and head-on beam-beam compensation studies in RHIC with lessons for the LHC (open access)

Long-range and head-on beam-beam compensation studies in RHIC with lessons for the LHC

Long-range as well as head-on beam-beam effects are expected to limit the LHC performance with design parameters. They are also important consideration for the LHC upgrades. To mitigate long-range effects, current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and analytical treatments. Electron lenses were proposed for both RHIC and the LHC to reduce the head-on beam-beam effect. We present the experimental long-range beam-beam program at RHIC and report on head-on compensations studies based on simulations.
Date: January 12, 2009
Creator: Fischer, W.; Luo, Y.; Abreu, N.; Calaga, R.; Montag, C.; Robert-Demolaize, G. et al.
System: The UNT Digital Library
Search for the Z(4430) at BABAR (open access)

Search for the Z(4430) at BABAR

We report the results of a search for Z(4430){sup -} decay to J/{psi}{pi}{sup -} or {psi}(2S){pi}{sup -} in B{sup -,0} {yields} J/{psi}{pi}{sup -} K{sup 0,+} and B{sup -,0} {yields} {psi}(2S){pi}{sup -}K{sup 0,+} decays. The data were collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e{sup +}e{sup -} collider operating at center of mass energy 10.58 GeV, and the sample corresponds to an integrated luminosity of 413 fb{sup -1}. Each K{pi}{sup -} mass distribution exhibits clear K*(892) and K*{sub 2}(1430) signals, and the efficiency-corrected spectrum is well-described by a superposition of the associated Breit-Wigner intensity distributions, together with an S-wave contribution obtained from the LASS I = 1/2 K{pi}{sup -} scattering amplitude measurements. Each K{pi}{sup -} angular distribution varies significantly in structure with K{pi}{sup -} mass, and is represented in terms of low-order Legendre polynomial moments. We find that each J/{psi}{pi}{sup -} or {psi}(2S){pi}{sup -} mass distribution is well-described by the reflection of the measured K{pi}{sup -} mass and angular distribution structures. We see no significant evidence for a Z(4430){sup -} signal for any of the processes investigated, neither in the total J/{psi}{pi}{sup -} or {psi}(2S){pi}{sup -} mass distribution, nor in the corresponding distributions for the regions of K{pi}{sup …
Date: January 12, 2009
Creator: Aubert, B.
System: The UNT Digital Library
Measurements of time-dependent CP asymmetries in B0 --> D(*)+D(*)- decays (open access)

Measurements of time-dependent CP asymmetries in B0 --> D(*)+D(*)- decays

We present new measurements of time-dependent CP asymmetries for B{sup 0} {yields} D{sup (*)+}d{sup (*)-} decays using (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected with the BABAR detector located at the PEP-II B Factory at the Stanford Linear Accelerator Center. We determine the CP-odd fraction of the B{sup 0} {yields} D*{sup +}D*{sup -} decays to be R{perpendicular} = 0.158 {+-} 0.028 {+-} 0.006 and find CP asymmetry parameters for the CP-even component of the decay S{sub +} = -0.76 {+-} 0.16 {+-} 0.04 and C{sub +} = 0.00 {+-} 0.12 {+-} 0.02. We measure S = -0.63{+-}0.36{+-}0.05 and C = -0.07{+-}0.23{+-}0.03 for B{sup 0} {yields} D{sup +}D{sup -}, S = -0.62{+-}0.21{+-}0.03 and C = 0.08 {+-} 0.17 {+-} 0.04 for B{sup 0} {yields} D*{sup +}D{sup -}, and S = -0.73 {+-} 0.23 {+-} 0.05 and C = 0.00 {+-} 0.17 {+-} 0.03 for B{sup 0} {yields} D{sup +}D*{sup -}. For the B{sup 0} {yields} D*{sup {+-}}D{sup {-+}} decays, we also determine the CP-violating asymmetry A = 0.008 {+-} 0.048 {+-} 0.013. In each case, the first uncertainty is statistical and the second is systematic. The measured values for the asymmetries are all consistent with the Standard Model.
Date: February 12, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
System: The UNT Digital Library
LIFE ESTIMATION OF HIGH LEVEL WASTE TANK STEEL FOR F-TANK FARM CLOSURE PERFORMANCE ASSESSMENT - 9310 (open access)

LIFE ESTIMATION OF HIGH LEVEL WASTE TANK STEEL FOR F-TANK FARM CLOSURE PERFORMANCE ASSESSMENT - 9310

High level radioactive waste (HLW) is stored in underground carbon steel storage tanks at the Savannah River Site. The underground tanks will be closed by removing the bulk of the waste, chemical cleaning, heel removal, stabilizing remaining residuals with tailored grout formulations, and severing/sealing external penetrations. The life of the carbon steel materials of construction in support of the performance assessment has been completed. The estimation considered general and localized corrosion mechanisms of the tank steel exposed to grouted conditions. A stochastic approach was followed to estimate the distributions of failures based upon mechanisms of corrosion accounting for variances in each of the independent variables. The methodology and results used for one-type of tank is presented.
Date: January 12, 2009
Creator: Subramanian, K; Bruce Wiersma, B & Stephen Harris, S
System: The UNT Digital Library
Heat of Combustion of Tantalum-Tungsten Oxide Thermite Composites (open access)

Heat of Combustion of Tantalum-Tungsten Oxide Thermite Composites

None
Date: November 12, 2009
Creator: Cervantes, O; Kuntz, J; Gash, A & Munir, Z
System: The UNT Digital Library
Challenges and opportunities in high-precision Be-10 measurements at CAMS (open access)

Challenges and opportunities in high-precision Be-10 measurements at CAMS

None
Date: October 12, 2009
Creator: Rood, D. H.; Hall, S.; Guilderson, T. P.; Finkel, R. C. & Brown, T. A.
System: The UNT Digital Library
Synthesis of High-Purity alpha-and beta-PbO and Possible Applications to Synthesis and Processing of Other Lead Oxide Materials (open access)

Synthesis of High-Purity alpha-and beta-PbO and Possible Applications to Synthesis and Processing of Other Lead Oxide Materials

The red, tetragonal form of lead oxide, alpha-PbO, litharge, and the yellow, orthorhombic form, beta-PbO, massicot, have been synthesized from lead(II) salts in aqueous media at elevated temperature. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the size, morphology, and crystallographic structural forms of the products. The role of impurities in the experimental synthesis of the materials and microstructural variations in the final products are described, and the implications of these observations with respect to the synthesis of different conducting lead oxides and other related materials are discussed.
Date: November 12, 2009
Creator: Perry, Dale L. & Wilkinson, T. J.
System: The UNT Digital Library
On-demand Overlay Networks for Large Scientific Data Transfers (open access)

On-demand Overlay Networks for Large Scientific Data Transfers

Large scale scientific data transfers are central to scientific processes. Data from large experimental facilities have to be moved to local institutions for analysis or often data needs to be moved between local clusters and large supercomputing centers. In this paper, we propose and evaluate a network overlay architecture to enable highthroughput, on-demand, coordinated data transfers over wide-area networks. Our work leverages Phoebus and On-demand Secure Circuits and AdvanceReservation System (OSCARS) to provide high performance wide-area network connections. OSCARS enables dynamic provisioning of network paths with guaranteed bandwidth and Phoebus enables the coordination and effective utilization of the OSCARS network paths. Our evaluation shows that this approach leads to improved end-to-end data transfer throughput with minimal overheads. The achievedthroughput using our overlay was limited only by the ability of the end hosts to sink the data.
Date: October 12, 2009
Creator: Ramakrishnan, Lavanya; Guok, Chin; Jackson, Keith; Kissel, Ezra; Swany, D. Martin & Agarwal, Deborah
System: The UNT Digital Library
Non-Proliferative, Thorium-Based, Core and Fuel Cycle for Pressurized Water Reactors (open access)

Non-Proliferative, Thorium-Based, Core and Fuel Cycle for Pressurized Water Reactors

Two of the major barriers to the expansion of worldwide adoption of nuclear power are related to proliferation potential of the nuclear fuel cycle and issues associated with the final disposal of spent fuel. The Radkowsky Thorium Fuel (RTF) concept proposed by Professor A. Radkowsky offers a partial solution to these problems. The main idea of the concept is the utilization of the seed-blanket unit (SBU) fuel assembly geometry which is a direct replacement for a 'conventional' assembly in either a Russian pressurized water reactor (VVER-1000) or a Western pressurized water reactor (PWR). The seed-blanket fuel assembly consists of a fissile (U) zone, known as seed, and a fertile (Th) zone known as blanket. The separation of fissile and fertile allows separate fuel management schemes for the thorium part of the fuel (a subcritical 'blanket') and the 'driving' part of the core (a supercritical 'seed'). The design objective for the blanket is an efficient generation and in-situ fissioning of the U233 isotope, while the design objective for the seed is to supply neutrons to the blanket in a most economic way, i.e. with minimal investment of natural uranium. The introduction of thorium as a fertile component in the nuclear fuel …
Date: July 12, 2009
Creator: M., Todosow; M., Todosow & Raitses, G. (BNL) Galperin, A. (Ben Gurion University)
System: The UNT Digital Library
HANFORD SITE LOW EXPOSURE PIPELINE REPAIR USING A NON-METALLIC COMPOSITE SYSTEM (open access)

HANFORD SITE LOW EXPOSURE PIPELINE REPAIR USING A NON-METALLIC COMPOSITE SYSTEM

At the Department of Energy, Richland Operations (DOE-RL) Hanford site in eastern Washington, a 350 mm (14 inch) diameter high density polyethylene (HDPE) pump recirculation pipeline failed at a bonded joint adjacent to a radiologically and chemically contaminated groundwater storage basin. The responsible DOE-RL contractor, CH2MHill Plateau Remediation Company, applied a fiberglass reinforced plastic (composite) field repair system to the failed joint. The system was devised specifically for the HDPE pipe repair at the Hanford site, and had not been used on this type of plastic piping previously. This paper introduces the pipe failure scenario, describes the options considered for repair and discusses the ultimate resolution of the problem. The failed pipeline was successfully returned to service with minimal impact on waste water treatment plant operating capacity. Additionally, radiological and chemical exposures to facility personnel were maintained as low as reasonably achievable (ALARA). The repair is considered a success for the near term, and future monitoring will prove whether the repair can be considered for long term service and as a viable alternative for similar piping failures at the Hanford site.
Date: November 12, 2009
Creator: Huth, R. J.
System: The UNT Digital Library
Next Generation Safeguards Initiative Workshop on Enhanced Recruiting for International Safeguards (open access)

Next Generation Safeguards Initiative Workshop on Enhanced Recruiting for International Safeguards

Brookhaven National Laboratory (BNL) hosted a Workshop on Enhanced Recruiting for International Safeguards October 22 and 23, 2008. The workshop was sponsored by DOE/NA-243 under the Next Generation Safeguards Initiative (NGSI). Placing well-qualified Americans in sufficient number and in key safeguards positions within the International Atomic Energy Agency’s (IAEA’s) Department of Safeguards is an important U.S. non-proliferation objective. The goal of the NGSI Workshop on Enhanced Recruiting for International Safeguards was to improve U.S. efforts to recruit U.S. citizens for IAEA positions in the Department of Safeguards. The participants considered the specific challenges of recruiting professional staff, safeguards inspectors, and managers. BNL’s International Safeguards Project Office invited participants from the U.S. Department of Energy, the IAEA, U.S. national laboratories, private industry, academia, and professional societies who are either experts in international safeguards or who understand the challenges of recruiting for technical positions. A final report for the workshop will be finalized and distributed in early 2009. The main finding of the workshop was the need for an integrated recruitment plan to take into account pools of potential candidates, various government and private agency stakeholders, the needs of the IAEA, and the NGSI human capital development plan. There were numerous findings …
Date: July 12, 2009
Creator: Pepper, S. E.; Rosenthal, M. D.; Fishbone, L. G.; Occhogrosso, D. M.; Lockwood, D.; Carroll, C. J. et al.
System: The UNT Digital Library
Nanosecond Mid-Infrared Detection for Pulse Radiolysis (open access)

Nanosecond Mid-Infrared Detection for Pulse Radiolysis

Pulse radiolysis, utilizing electron pulses from accelerators, is the definitive method for adding single positive or negative charges to molecules. It is also among the most effective means for creating free radicals. Such species are particularly important in applications such as redox catalysis relevant to solar energy conversion and advanced nuclear energy systems. Coupled with fast UV-visible detection, pulse radiolysis has become an extremely powerful method for monitoring the kinetics of the subsequent reactions of these species on timescales ranging from picoseconds to seconds. However, in many important contexts the radicals formed are difficult to identify due to their broad and featureless UV-visible absorption spectra. Time-resolved infrared (TRIR) absorption spectroscopy is a powerful structural probe of short-lived intermediates, which allows multiple transient species to be clearly identified and simultaneously monitored in a single process. Unfortunately, due to technical challenges the coupling of fast (sub-millisecond) TRIR with pulse radiolysis has received little attention, being confined to gas-phase studies. Taking advantage of recent developments in mid-IR laser technology, we have recently begun developing nanosecond TRIR detection methodologies for condensed-phase samples at our Laser Electron Accelerator Facility (LEAF). The results of preliminary pulse radiolysis-TRIR investigations on the formation of the one-electron reduced forms …
Date: July 12, 2009
Creator: Grills, D. C.; Preses, J. M.; Wishart, J. F. & Cook, A. R.
System: The UNT Digital Library
A Successful Case Study of Small Business Energy Efficiency and Demand Response with Communicating Thermostats (open access)

A Successful Case Study of Small Business Energy Efficiency and Demand Response with Communicating Thermostats

This report documents a field study of 78 small commercial customers in the Sacramento Municipal Utility District service territory who volunteered for an integrated energy-efficiency/demand-response (EE-DR) program in the summer of 2008. The original objective for the pilot was to provide a better understanding of demand response issues in the small commercial sector. Early findings justified a focus on offering small businesses (1) help with the energy efficiency of their buildings in exchange for occasional load shed, and (2) a portfolio of options to meet the needs of a diverse customer sector. To meet these expressed needs, the research pilot provided on-site energy efficiency advice and offered participants several program options, including the choice of either a dynamic rate or monthly payment for air-conditioning setpoint control. Overall results show that pilot participants had energy savings of 20%, and the potential for an additional 14% to 20% load drop during a 100 F demand response event. In addition to the efficiency-related bill savings, participants on the dynamic rate saved an estimated 5% on their energy costs compared to the standard rate. About 80% of participants said that the program met or surpassed their expectations, and three-quarters said they would probably or …
Date: August 12, 2009
Creator: Herter, Karen; Wayland, Seth & Rasin, Josh
System: The UNT Digital Library
Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium at the EMS 2009 Annual Meeting - September 2006 (open access)

Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium at the EMS 2009 Annual Meeting - September 2006

The low dose symposium thoughtfully addressed controversy of risk from low dose radiation exposure, hormesis and radon therapy. The stem cell symposium cogently considered the role of DNA damage and repair in hematopoietic stem cells underlying aging and malignancy and provocatively presented evidence that stem cells may have distinct morphologies and replicative properties, as well as special roles in cancer initiation. In the epigenetics symposium, studies illustrated the long range interaction of epigenetic mechanisms, the roles of CTCF and BORIS in region/specific regulation of epigenetic processes, the impact of DNA damage on epigenetic processes as well as links between epigenetic mechanisms and early nutrition and bystander effects.
Date: November 12, 2009
Creator: Morgan, William F.; von Borstel, Robert C.; Brenner, David; Redpath, J. Leslie; Erickson, Barbra E. & Brooks, Antone L.
System: The UNT Digital Library
Using an IIDC/DCAM camera for beam display and analysis (open access)

Using an IIDC/DCAM camera for beam display and analysis

An IIDC/DCAM camera is used to the RHIC beams as they pass through a hydrogen jet. The data is transferred over a 1394 bus to a computer with a Linux operating system. A software process on that computer collects the individual frames and packages them into parameters within the RHIC control system's framework. This information is packaged to continuously update two primary types of clients: One type is responsible for near-real-time display of the images; useful in comfort displays, etc. The second is responsible for collecting data used in analysis of beam dynamics and properties like luminosity.
Date: October 12, 2009
Creator: Olsen,R.H.; Gassner, D. & Hoff, L. T.
System: The UNT Digital Library
Proliferation Risk Reduction Study of Alternative Spent Fuel Processing (open access)

Proliferation Risk Reduction Study of Alternative Spent Fuel Processing

This paper presents the results of an evaluation of the relative proliferation risks of particular reprocessing technologies focusing on COEX, UREX+, and pyroprocessing
Date: July 12, 2009
Creator: Bari, R. A.; Phillips, J.; Pilat, J.; Rochau, G.; Therios, I.; Wigeland, R. et al.
System: The UNT Digital Library
Improving Memory Subsystem Performance Using ViVA: Virtual Vector Architecture (open access)

Improving Memory Subsystem Performance Using ViVA: Virtual Vector Architecture

The disparity between microprocessor clock frequencies and memory latency is a primary reason why many demanding applications run well below peak achievable performance. Software controlled scratchpad memories, such as the Cell local store, attempt to ameliorate this discrepancy by enabling precise control over memory movement; however, scratchpad technology confronts the programmer and compiler with an unfamiliar and difficult programming model. In this work, we present the Virtual Vector Architecture (ViVA), which combines the memory semantics of vector computers with a software-controlled scratchpad memory in order to provide a more effective and practical approach to latency hiding. ViVA requires minimal changes to the core design and could thus be easily integrated with conventional processor cores. To validate our approach, we implemented ViVA on the Mambo cycle-accurate full system simulator, which was carefully calibrated to match the performance on our underlying PowerPC Apple G5 architecture. Results show that ViVA is able to deliver significant performance benefits over scalar techniques for a variety of memory access patterns as well as two important memory-bound compact kernels, corner turn and sparse matrix-vector multiplication -- achieving 2x-13x improvement compared the scalar version. Overall, our preliminary ViVA exploration points to a promising approach for improving application performance …
Date: January 12, 2009
Creator: Gebis, Joseph; Oliker, Leonid; Shalf, John; Williams, Samuel & Yelick, Katherine
System: The UNT Digital Library
Energy Smart Management of Scientific Data (open access)

Energy Smart Management of Scientific Data

Scientific data centers comprised of high-powered computing equipment and large capacity disk storage systems consume considerable amount of energy. Dynamic power management techniques (DPM) are commonly used for saving energy in disk systems. These involve powering down disks that exhibit long idle periods and placing them in standby mode. A file request from a disk in standby mode will incur both energy and performance penalties as it takes energy (and time) to spin up the disk before it can serve a file. For this reason, DPM has to make decisions as to when to transition the disk into standby mode such that the energy saved is greater than the energy needed to spin it up again and the performance penalty is tolerable. The length of the idle period until the DPM decides to power down a disk is called idlenessthreshold. In this paper, we study both analytically and experimentally dynamic power management techniques that save energy subject to performance constraints on file access costs. Based on observed workloads of scientific applications and disk characteristics, we provide a methodology for determining file assignment to disks and computing idleness thresholds that result in significant improvements to the energy saved by existing DPMsolutions …
Date: April 12, 2009
Creator: Otoo, Ekow; Rotem, Dron & Tsao, Shih-Chiang
System: The UNT Digital Library
Shipment of Small Quantities of Unspecified Radioactive Material in Chalfant Packagings (open access)

Shipment of Small Quantities of Unspecified Radioactive Material in Chalfant Packagings

In the post 6M era, radioactive materials package users are faced with the disciplined operations associated with use of Certified Type B packagings. Many DOE, commercial and academic programs have a requirement to ship and/or store small masses of poorly characterized or unspecified radioactive material. For quantities which are small enough to be fissile exempt and have low radiation levels, the materials could be transported in a package which provides the required containment level. Because their Chalfant type containment vessels meet the highest standard of containment (helium leak-tight), the 9975, 9977, and 9978 are capable of transporting any of these contents. The issues associated with certification of a high-integrity, general purpose package for shipping small quantities of unspecified radioactive material are discussed and certification of the packages for this mission is recommended.
Date: June 12, 2009
Creator: Smith, Allen; Abramczyk, Glenn; Nathan, Steven & Bellamy, Steve
System: The UNT Digital Library
Trials, tribulations, and pitfalls using commercial instruments for data acquisition (open access)

Trials, tribulations, and pitfalls using commercial instruments for data acquisition

Brookhaven National Laboratory's Relativistic Heavy Ion Collider (RHIC) uses many commercially available instruments - for example spectrum analyzers, oscilloscopes, digital volt meters, signal generators - as integral parts of instrumentation and control systems. Typically these systems are remotely controlled. Using commercial instruments has many benefits. Manufactures have the skill, knowledge, and experience to produce high quality products. The price performance ratio is hard to duplicate. There are also disadvantages. Proprietary interfaces, single platform drivers, and reliable operation provide challenges for implementation and unattended operation. Several of the systems used at RHIC will be described. Their issues and solutions will be presented.
Date: October 12, 2009
Creator: Lee,R.C.; Olsen, R. H. & Unger, K. L.
System: The UNT Digital Library