ABSTRACT: The Community Environmental Monitoring Program: Reducing Public Perception of Risk Through Stakeholder Involvement (open access)

ABSTRACT: The Community Environmental Monitoring Program: Reducing Public Perception of Risk Through Stakeholder Involvement

Between 1951 and 1992, 928 nuclear tests were conducted at the Nevada Test Site (NTS), including 100 atmospheric and 828 underground tests. Initial public reaction to the tests was largely supportive, but by the late 1950s this began to change, largely as a result of fear of the potential for adverse health effects to be caused by exposure to ionizing radiation resulting from the tests. The nuclear power plant accident at Three Mile Island in 1979 served to heighten these fears, as well as foster a general distrust of the federal agencies involved and low public confidence in monitoring results. Modeled after a similar program that involved the public in monitoring activities around the Three Mile Island nuclear power plant, the Community Environmental Monitoring Program (CEMP) has promoted stakeholder involvement, awareness, and understanding of radiological surveillance in communities surrounding the NTS since 1981. It involves stakeholders in the operation, data collection, and dissemination of information obtained from a network of 29 stations across a wide area of Nevada, Utah, and California. It is sponsored by the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) and administered by the Desert Research Institute (DRI) of the Nevada System …
Date: February 28, 2007
Creator: Hartwell, T.
Object Type: Article
System: The UNT Digital Library
ACRF Ingest Software Status: New, Current, and Future - February 2007 (open access)

ACRF Ingest Software Status: New, Current, and Future - February 2007

The purpose of this report is to provide status of the ingest software used to process instrument data for the Atmospheric Radiation Measurement Program Climate Research Facility (ACRF). The report is divided into 4 sections: (1) for news about ingests currently under development, (2) for current production ingests, (3) for future ingest development plans, and (4) for information on retired ingests.
Date: February 28, 2007
Creator: Koontz, A. S.; Choudhury, S.; Ermold, B. D. & Gaustad, K. L.
Object Type: Report
System: The UNT Digital Library
ANALYSIS OF TANK 28F SALTCAKE CORE SAMPLES FTF-456 - 467 (open access)

ANALYSIS OF TANK 28F SALTCAKE CORE SAMPLES FTF-456 - 467

Twelve LM-75 core samplers from Tank 28F sampling were received by SRNL for saltcake characterization. Of these, nine samplers contained mixtures of free liquid and saltcake, two contained only liquid, and one was empty. The saltcake contents generally appeared wet. A summary of the major tasks performed in this work are as follows: (1) Individual saltcake segments were extruded from the samplers and separated into saltcake and free liquid portions. (2) Free liquids were analyzed to estimate the amount of traced drill-string fluid contained in the samples. (3) The saltcake from each individual segment was homogenized, followed by analysis in duplicate. The analysis used more cost-effective and bounding radiochemical analyses rather than using the full Saltstone WAC suite. (4) A composite was created using an approximately equal percentage of each segment's saltcake contents. Supernatant liquid formed upon creation of the composite was decanted prior to use of the composite, but the composite was not drained. (5) A dissolution test was performed on the sample by contacting the composite with water at a 4:1 mass ratio of water to salt. The resulting soluble and insoluble fractions were analyzed. Analysis focused on a large subset of the Saltstone WAC constituents.
Date: February 28, 2007
Creator: Martino, C; Daniel McCabe, D; Tommy Edwards, T & Ralph Nichols, R
Object Type: Report
System: The UNT Digital Library
Appliances, Lighting, Electronics, and Miscellaneous EquipmentElectricity Use in New Homes (open access)

Appliances, Lighting, Electronics, and Miscellaneous EquipmentElectricity Use in New Homes

The "Other" end-uses (appliances, lighting, electronics, andmiscellaneous equipment) continue to grow. This is particularly true innew homes, where increasing floor area and amenities are leading tohigher saturation of these types of devices. This paper combines thefindings of several field studies to assess the current state ofknowledge about the "Other" end-uses in new homes. The field studiesinclude sub-metered measurements of occupied houses in Arizona, Florida,and Colorado, as well as device-level surveys and power measurements inunoccupied new homes. We find that appliances, lighting, electronics, andmiscellaneous equipment can consume from 46 percent to 88 percent ofwhole-house electricity use in current low-energy homes. Moreover, theannual consumption for the "Other" end-uses is not significantly lower innew homes (even those designed for low energy use) compared to existinghomes. The device-level surveys show that builder-installed equipment isa significant contributor to annual electricity consumption, and certaindevices that are becoming more common in new homes, such as structuredwiring systems, contribute significantly to this power consumption. Thesefindings suggest that energy consumption by these "Other" end uses isstill too large to allow cost-effective zero-energy homes.
Date: February 28, 2007
Creator: Brown, Richard E.; Rittelman, William; Parker, Danny & Homan,Gregory
Object Type: Article
System: The UNT Digital Library
Asynchronous Event-Driven Particle Algorithms (open access)

Asynchronous Event-Driven Particle Algorithms

We present in a unifying way the main components of three examples of asynchronous event-driven algorithms for simulating physical systems of interacting particles. The first example, hard-particle molecular dynamics (MD), is well-known. We also present a recently-developed diffusion kinetic Monte Carlo (DKMC) algorithm, as well as a novel event-driven algorithm for Direct Simulation Monte Carlo (DSMC). Finally, we describe how to combine MD with DSMC in an event-driven framework, and discuss some promises and challenges for event-driven simulation of realistic physical systems.
Date: February 28, 2007
Creator: Donev, A
Object Type: Article
System: The UNT Digital Library
Borehole Summary Report for C4997 Rotary Drilling, WTP Seismic Boreholes Project, CY 2006 (open access)

Borehole Summary Report for C4997 Rotary Drilling, WTP Seismic Boreholes Project, CY 2006

The following Final Geologic Borehole Report briefly describes the drilling of a single borehole at the Waste Treatment Plant (WTP) on the Hanford, Washington, U.S. Department of Energy (DOE) reservation. The location of the WTP is illustrated in Figure 1-1. The borehole was designated as “C4997”, and was drilled to obtain seismic and lithologic data for the Pretreatment Facility and High-Level Waste Vitrification Plant in the WTP. Borehole C4997 was drilled and logged to a total depth of 1428 ft below ground surface (bgs) on October 8, 2006, and was located approximately 150 ft from a recently cored borehole, designated as “C4998”. Pacific Northwest National Laboratory (PNNL) determined the locations for C4997, C4998, and other boreholes at the WTP in cooperation with the U.S. Army Corps of Engineers (USACE) Review Panel, and the Defense Nuclear Facilities Safety Board (DNFSB). The total depth of Borehole C4997 was also determined by PNNL.
Date: February 28, 2007
Creator: Difebbo, Thomas J.
Object Type: Report
System: The UNT Digital Library
Borehole Summary Report for Waste Treatment Plant Seismic Borehole C4993 (open access)

Borehole Summary Report for Waste Treatment Plant Seismic Borehole C4993

A core hole (C4998) and three boreholes (C4993, C4996, and C4997) were drilled to acquire stratigraphic and downhole seismic data to model potential seismic impacts and to refine design specifications and seismic criteria for the Waste Treatment Plant (WTP) under construction on the Hanford Site. Borehole C4993 was completed through the Saddle Mountains Basalt, the upper portion of the Wanapum Basalt, and associated sedimentary interbeds, to provide a continuous record of the rock penetrated by all four holes and to provide access to the subsurface for geophysical measure¬ment. Presented and compiled in this report are field-generated records for the deep mud rotary borehole C4993 at the WTP site. Material for C4993 includes borehole logs, lithologic summary, and record of rock chip samples collected during drilling through the months of August through early October. The borehole summary report also includes documentation of the mud rotary drilling, borehole logging, and sample collection.
Date: February 28, 2007
Creator: Rust, Colleen F.; Barnett, D. BRENT; Bowles, Nathan A. & Horner, Jake A.
Object Type: Report
System: The UNT Digital Library
Cell shape regulates global histone acetylation in human mammary epithelial cells (open access)

Cell shape regulates global histone acetylation in human mammary epithelial cells

Extracellular matrix (ECM) regulates cell morphology and gene expression in vivo; these relationships are maintained in three-dimensional (3D) cultures of mammary epithelial cells. In the presence of laminin-rich ECM (lrECM), mammary epithelial cells round up and undergo global histone deacetylation, a process critical for their functional differentiation. However, it remains unclear whether lrECM-dependent cell rounding and global histone deacetylation are indeed part of a common physical-biochemical pathway. Using 3D cultures as well as nonadhesive and micropatterned substrata, here we showed that the cell 'rounding' caused by lrECM was sufficient to induce deacetylation of histones H3 and H4 in the absence of biochemical cues. Microarray and confocal analysis demonstrated that this deacetylation in 3D culture is associated with a global increase in chromatin condensation and a reduction in gene expression. Whereas cells cultured on plastic substrata formed prominent stress fibers, cells grown in 3D lrECM or on micropatterns lacked these structures. Disruption of the actin cytoskeleton with cytochalasin D phenocopied the lrECM-induced cell rounding and histone deacetylation. These results reveal a novel link between ECM-controlled cell shape and chromatin structure, and suggest that this link is mediated by changes in the actin cytoskeleton.
Date: February 28, 2007
Creator: Le Beyec, Johanne; Xu, Ren; Lee, Sun-Young; Nelson, Celeste M.; Rizki, Aylin; Alcaraz, Jordi et al.
Object Type: Article
System: The UNT Digital Library
Chunking of Large Multidimensional Arrays (open access)

Chunking of Large Multidimensional Arrays

Data intensive scientific computations as well on-lineanalytical processing applications as are done on very large datasetsthat are modeled as k-dimensional arrays. The storage organization ofsuch arrays on disks is done by partitioning the large global array intofixed size hyper-rectangular sub-arrays called chunks or tiles that formthe units of data transfer between disk and memory. Typical queriesinvolve the retrieval of sub-arrays in a manner that accesses all chunksthat overlap the query results. An important metric of the storageefficiency is the expected number of chunks retrieved over all suchqueries. The question that immediately arises is "what shapes of arraychunks give the minimum expected number of chunks over a query workload?"In this paper we develop two probabilistic mathematical models of theproblem and provide exact solutions using steepest descent and geometricprogramming methods. Experimental results, using synthetic workloads onreal life data sets, show that our chunking is much more efficient thanthe existing approximate solutions.
Date: February 28, 2007
Creator: Rotem, Doron; Otoo, Ekow J. & Seshadri, Sridhar
Object Type: Report
System: The UNT Digital Library
Critical issues for high-brightness heavy-ion beams- prioritized (open access)

Critical issues for high-brightness heavy-ion beams- prioritized

This study group was initiated to consider whether there were any ''show-stopper'' issues with accelerators for heavy-ion warm-dense matter (WDM) and heavy-ion inertial fusion energy (HIF), and to prioritize them. Showstopper issues would appear as limits to beam current; that is, the beam would be well-behaved below the current limit, and significantly degraded in current or emittance if the current limit were exceeded at some region of an accelerator. We identified 14 issues: 1-6 could be addressed in the near term, 7-10 are potentially attractive solutions to performance and cost issues but are not yet fully characterized, 11-12 involve multibeam effects that cannot be more than partially studied in near-term facilities, and 13-14 involve new issues that are present in some novel driver concepts. Comparing the issues with the new experimental, simulation, and theoretical tools that we have developed, it is apparent that our new capabilities provide an opportunity to re-examine and significantly increase our understanding of the number one issue--halo growth and mitigation.
Date: February 28, 2007
Creator: Molvik, A. W.; Cohen, R.; Davidson, R.; Faltens, A.; Friedman, A.; Grisham, L. et al.
Object Type: Report
System: The UNT Digital Library
Dark Matter Burners (open access)

Dark Matter Burners

We show that a star orbiting close enough to an adiabatically grown supermassive black hole (SMBH) can capture weakly interacting massive particles (WIMPs) at an extremely high rate. The stellar luminosity due to annihilation of captured WIMPs in the stellar core may be comparable to or even exceed the luminosity of the star due to thermonuclear burning. The model thus predicts the existence of unusual stars, essentially WIMP burners, in the vicinity of a SMBH. We find that the most efficient WIMP burners are stars with degenerate electron cores, e.g. white dwarfs (WDs); such WDs may have a very high surface temperature. If found, such stars would provide evidence for the existence of particle dark matter and can possibly be used to establish its density profile. On the other hand, the lack of such unusual stars may provide constraints on the WIMP density near the SMBH, as well as the WIMP-nucleus scattering and pair annihilation cross-sections.
Date: February 28, 2007
Creator: Moskalenko, Igor V.; /Stanford U., HEPL & Wai, Lawrence L.
Object Type: Article
System: The UNT Digital Library
Diode-pumped 22-W average-power uv laser with user-selectable pulse width and >50% conversion efficiency (open access)

Diode-pumped 22-W average-power uv laser with user-selectable pulse width and >50% conversion efficiency

A diode-pumped Nd:YAG laser (39 W at 1064 nm) has been frequency tripled with >50% conversion efficiency (22 W at 355 nm). The laser operates at 300 Hz with pulse energies >73 mJ.
Date: February 28, 2007
Creator: Honig, John & Halpin, John
Object Type: Article
System: The UNT Digital Library
Early Gas Stripping as the Origin of the Darkest Galaxies in the Universe (open access)

Early Gas Stripping as the Origin of the Darkest Galaxies in the Universe

The known galaxies most dominated by dark matter (Draco, Ursa Minor and Andromeda IX) are satellites of the Milky Way and the Andromeda galaxies. They are members of a class of faint galaxies, devoid of gas, known as dwarf spheroidals, and have by far the highest ratio of dark to luminous matter. None of the models proposed to unravel their origin can simultaneously explain their exceptional dark matter content and their proximity to a much larger galaxy. Here we report simulations showing that the progenitors of these galaxies were probably gas-dominated dwarf galaxies that became satellites of a larger galaxy earlier than the other dwarf spheroidals. We find that a combination of tidal shocks and ram pressure swept away the entire gas content of such progenitors about ten billion years ago because heating by the cosmic ultraviolet background kept the gas loosely bound: a tiny stellar component embedded in a relatively massive dark halo survived until today. All luminous galaxies should be surrounded by a few extremely dark-matter-dominated dwarf spheroidal satellites, and these should have the shortest orbital periods among dwarf spheroidals because they were accreted early.
Date: February 28, 2007
Creator: Mayer, Lucio; Kazantzidis, Stelios; Mastropietro, Chiara & Wadsley, James
Object Type: Article
System: The UNT Digital Library
Emergency Response Equipment and Related Training: Airborne Radiological Computer System (Model II) (open access)

Emergency Response Equipment and Related Training: Airborne Radiological Computer System (Model II)

The materials included in the Airborne Radiological Computer System, Model-II (ARCS-II) were assembled with several considerations in mind. First, the system was designed to measure and record the airborne gamma radiation levels and the corresponding latitude and longitude coordinates, and to provide a first overview look of the extent and severity of an accident's impact. Second, the portable system had to be light enough and durable enough that it could be mounted in an aircraft, ground vehicle, or watercraft. Third, the system must control the collection and storage of the data, as well as provide a real-time display of the data collection results to the operator. The notebook computer and color graphics printer components of the system would only be used for analyzing and plotting the data. In essence, the provided equipment is composed of an acquisition system and an analysis system. The data can be transferred from the acquisition system to the analysis system at the end of the data collection or at some other agreeable time.
Date: February 28, 2007
Creator: Colton, David P.
Object Type: Report
System: The UNT Digital Library
Entry Boreholes Summary Report for the Waste Treatment Plant Seismic Boreholes Project (open access)

Entry Boreholes Summary Report for the Waste Treatment Plant Seismic Boreholes Project

This report describes the 2006 fiscal year field activities associated with the installation of four cable-tool-drilled boreholes located within the boundary of the Waste Treatment Plant (WTP), DOE Hanford site, Washington. The cable-tool-drilled boreholes extend from surface to ~20 ft below the top of basalt and were utilized as cased entry holes for three deep boreholes (approximately 1400 ft) that were drilled to support the acquisition of sub-surface geophysical data, and one deep corehole (1400 ft) that was drilled to acquire continuous core samples from underlying basalt and sedimentary interbeds. The geophysical data acquired from these boreholes will be integrated into a seismic response model that will provide the basis for defining the seismic design criteria for the WTP facilities.
Date: February 28, 2007
Creator: Horner, Jake A.
Object Type: Report
System: The UNT Digital Library
An Explicit Time-Domain Hybrid Formulation Based on the Unified Boundary Condition (open access)

An Explicit Time-Domain Hybrid Formulation Based on the Unified Boundary Condition

An approach to stabilize the two-surface, time domain FEM/BI hybrid by means of a unified boundary condition is presented. The first-order symplectic finite element formulation [1] is used along with a version of the unified boundary condition of Jin [2] reformulated for Maxwell's first-order equations in time to provide both stability and accuracy over the first-order ABC. Several results are presented to validate the numerical solutions. In particular the dipole in a free-space box is analyzed and compared to the Dirchlet boundary condition of Ziolkowski and Madsen [3] and to a Neuman boundary condition approach.
Date: February 28, 2007
Creator: Madsen, N; Fasenfest, B J; White, D; Stowell, M; Jandhyala, V; Pingenot, J et al.
Object Type: Report
System: The UNT Digital Library
Final Report, DOE Award Number DE-FG02-02ER45964, Electromagnetic Properties of Matter at X-ray Wavelengths (open access)

Final Report, DOE Award Number DE-FG02-02ER45964, Electromagnetic Properties of Matter at X-ray Wavelengths

We report results of a collaborative study of photon and charged-particle interactions with matter between the University of Vermont and Argonne and Brookhaven National Laboratories. A major goal was to extend the study of electromagnetic properties of selected materials to as wide a spectral range as possible. This broad approach discloses systematic trends not apparent in isolated measurements and exploits the power of dispersion analysis and sum-rule constraints. Emphasis was largely on UV and X-ray processes and capitalized on the wide range of photon energies available at NSLS. A key finding is that, under favorable circumstances, dispersion theory relates dispersive processes (e.g. refractive index, dielectric constant) to spectral moments of absorptive processes. This appears to be a new method in optics; it yields significant simplifications and provides a precise, model-independent characterization of optical materials. Problems addressed included a) x-ray magnetooptics; b) UV/soft-x-ray processes in insulators and their contribution to visible dispersion; c) demonstration of moments/dispersion analysis in glasses and applications to fiber-optic systems; d) the optical constants of silicon and their application to the stopping power of silicon for charged-particles. Results include: ● Resolution of a long-standing conflict over the relation between x-ray Faraday rotation and x-ray magnetic circular dichroism. …
Date: February 28, 2007
Creator: Smith, David Y.
Object Type: Report
System: The UNT Digital Library
Final Technical Report (open access)

Final Technical Report

The Industrial Assessment Center at Iowa State University provided 93 companies in 5 states with Industrial Assessments. The total potential energy cost savings is approximately $11.43 million. The savings includes approximately 38.6 million kWh of electrical energy, 65 MW of electrical demand, and 426,000 MMBtu of natural gas. The center employed and trained 43 engineering students and involved 4 engineering faculty from both the Industrial and Mechanical Engineering Departments. Benefits to the public include increased productivity of manufacturing plants, training of engineering students in the area of industrial energy efficiency and reduced energy consumption.
Date: February 28, 2007
Creator: Maxwell, Gregory M.
Object Type: Report
System: The UNT Digital Library
Final Technical Report (open access)

Final Technical Report

The Industrial Assessment Center program at North Carolina State University has conducted one hundred industrial assessments of small and medium sized manufacturers in North Carolina, South Carolina, and Virginia. Reports were submitted to each facility that included a brief description of the plant, historical energy use, and a technical analysis of potential energy efficiency savings, waste reduction, and productivity savings. Seven hundred thirty eight conservation measures were recommended with total annual cost savings in excess of $18 million. The NCSU IAC has worked with other government and private entities to deliver energy efficiency and conservation services. We have worked closely with the NCSU Industrial Extension Service, the Manufacturer’s Extension Partnership (MEP), and the North Carolina State Energy Office to provide follow-up technical help and financial assistance in implementing conservation recommendations. In addition to these organizations, the NCSU IAC has also worked with the NC Department of Pollution Prevention and Environmental Assistance, the NC Solar Center, Advanced Energy Corporation, Duke Power, Progress Energy, Dominion Power, and the City of Danville, Virginia. Eighteen undergraduate and twenty graduate students were exposed to a variety of manufacturing processes, trained on plant safety, and taught the use of various types of data collection equipment. The …
Date: February 28, 2007
Creator: Eckerlin, H, M, PhD PE; Leach, J, W, PhD PE & Terry, S, D, PhD PE
Object Type: Report
System: The UNT Digital Library
Final technical report for "Frontiers in Plasma Kinetic Theory" (open access)

Final technical report for "Frontiers in Plasma Kinetic Theory"

This report summarizes the results and activities funded by this three-year award.
Date: February 28, 2007
Creator: Chandran, Benjamin D. G.
Object Type: Report
System: The UNT Digital Library
Geology of the Waste Treatment Plant Seismic Boreholes (open access)

Geology of the Waste Treatment Plant Seismic Boreholes

In 2006, DOE-ORP initiated the Seismic Boreholes Project (SBP) to emplace boreholes at the Waste Treatment Plant (WTP) site in order to obtain direct Vs measurements and other physical property measurements in Columbia River basalt and interbedded sediments of the Ellensburg Formation. The goal was to reduce the uncertainty in the response spectra and seismic design basis, and potentially recover design margin for the WTP. The characterization effort within the deep boreholes included 1) downhole measurements of the velocity properties of the suprabasalt, basalt, and sedimentary interbed sequences, 2) downhole measurements of the density of the subsurface basalt and sediments, and 3) confirmation of the geometry of the contact between the various basalt and interbedded sediments through examination of retrieved core from the corehole and data collected through geophysical logging of each borehole. This report describes the results of the geologic studies from three mud-rotary boreholes and one cored borehole at the WTP. All four boreholes penetrated the entire Saddle Mountains Basalt and the upper part of the Wanapum Basalt where thick sedimentary interbeds occur between the lava flows. The basalt flows penetrated in Saddle Mountains Basalt included the Umatilla Member, Esquatzel Member, Pomona Member and the Elephant Mountain Member. …
Date: February 28, 2007
Creator: Barnett, D. BRENT; Bjornstad, Bruce N.; Fecht, Karl R.; Lanigan, David C.; Reidel, Steve & Rust, Colleen F.
Object Type: Report
System: The UNT Digital Library
The Grand Challenge of Managing the Petascale Facility. (open access)

The Grand Challenge of Managing the Petascale Facility.

This report is the result of a study of networks and how they may need to evolve to support petascale leadership computing and science. As Dr. Ray Orbach, director of the Department of Energy's Office of Science, says in the spring 2006 issue of SciDAC Review, 'One remarkable example of growth in unexpected directions has been in high-end computation'. In the same article Dr. Michael Strayer states, 'Moore's law suggests that before the end of the next cycle of SciDAC, we shall see petaflop computers'. Given the Office of Science's strong leadership and support for petascale computing and facilities, we should expect to see petaflop computers in operation in support of science before the end of the decade, and DOE/SC Advanced Scientific Computing Research programs are focused on making this a reality. This study took its lead from this strong focus on petascale computing and the networks required to support such facilities, but it grew to include almost all aspects of the DOE/SC petascale computational and experimental science facilities, all of which will face daunting challenges in managing and analyzing the voluminous amounts of data expected. In addition, trends indicate the increased coupling of unique experimental facilities with computational facilities, …
Date: February 28, 2007
Creator: Aiken, R. J. & Science, Mathematics and Computer
Object Type: Report
System: The UNT Digital Library
Gravi-Leptogenesis: Leptogenesis From Gravity Waves in Pseudo-Scalar Driven Inflation Models (open access)

Gravi-Leptogenesis: Leptogenesis From Gravity Waves in Pseudo-Scalar Driven Inflation Models

In this talk we present a mechanism for leptogenesis which is based on gravity waves produced during inflation. We show that when inflation is driven by a pseudo-scalar field the metric perturbations generated during inflation can become birefringent, therefore giving a non-vanishing contribution to the gravitational triangle anomaly and sourcing lepton anti-lepton asymmetry. As this asymmetry is sourced by the fields which are active during inflation, it is not washed out or diluted by inflation. The amount of matter asymmetry generated in our model can be of realistic size for the parameters within the range of some inflationary scenarios and grand unified theories.
Date: February 28, 2007
Creator: Alexander, S. H.; Peskin, Michael E. & Sheikh-Jabbari, M. M.
Object Type: Article
System: The UNT Digital Library
High-Efficiency Absorber for Damping the Transverse Wake Fields (open access)

High-Efficiency Absorber for Damping the Transverse Wake Fields

Transverse wake fields generated by intense beams may propagate long distances in the vacuum chamber and dissipate power in different shielded elements such as bellows, vacuum valves or vacuum pumps. Induced heating in these elements may be high enough to deteriorate vacuum conditions. We have developed a broadband water-cooled bellows-absorber to capture and damp these harmful transverse fields without impacting the longitudinal beam impedance. Experimental results at the PEP-II SLAC B-factory demonstrate high efficiency of this device. This absorber may be useful in other machines like synchrotron light sources or International Linear Collider.
Date: February 28, 2007
Creator: Novokhatski, A.; Seeman, J. & Weathersby, S.
Object Type: Article
System: The UNT Digital Library