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GHG Mitigation Potential, Costs and Benefits in Global Forests: ADynamic Partial Equilibrium Approach (open access)

GHG Mitigation Potential, Costs and Benefits in Global Forests: ADynamic Partial Equilibrium Approach

This paper reports on the global potential for carbonsequestration in forest plantations, and the reduction of carbonemissions from deforestation, in response to six carbon price scenariosfrom 2000 to 2100. These carbon price scenarios cover a range typicallyseen in global integrated assessment models. The world forest sector wasdisaggregated into tenregions, four largely temperate, developedregions: the European Union, Oceania, Russia, and the United States; andsix developing, mostly tropical, regions: Africa, Central America, China,India, Rest of Asia, and South America. Three mitigation options -- long-and short-rotation forestry, and the reduction of deforestation -- wereanalyzed using a global dynamic partial equilibrium model (GCOMAP). Keyfindings of this work are that cumulative carbon gain ranges from 50.9 to113.2 Gt C by 2100, higher carbon prices early lead to earlier carbongain and vice versa, and avoided deforestation accounts for 51 to 78percent of modeled carbon gains by 2100. The estimated present value ofcumulative welfare change in the sector ranges from a decline of $158billion to a gain of $81 billion by 2100. The decline is associated witha decrease in deforestation.
Date: March 22, 2005
Creator: Sathaye, Jayant; Makundi, Willy; Dale, Larry; Chan, Peter & Andrasko, Kenneth
Object Type: Report
System: The UNT Digital Library
Recent Developments in Neutrino Science: A Whole Lot About Almost Nothing (open access)

Recent Developments in Neutrino Science: A Whole Lot About Almost Nothing

Results from Super-K, SNO, and KamLAND provide strong evidence that neutrinos undergo flavor-changing oscillations and therefore have non-zero mass. The {nu}-disappearance observations by KamLAND, assuming CPT conservation, point to matter enhanced (MSW) oscillations with large mixing angles as the solution to the solar neutrino problem--a result consistent with the MSW parameters recently defined by these experiments. This requires that the observed neutrino flavors (e, {mu}, and tau) are not mass eigenstates, but are linear combinations of the mass eigenstates of the neutrino. However, such oscillation experiments can only determine the differences in the masses of the neutrinos, not the absolute scale of neutrino mass. What can be inferred from these experiments is that at least one species of neutrino has a mass greater than 55 meV. In fact, the WMAP observations of large-scale structure point to a sum-neutrino mass of {approx} 0.7 eV (roughly 0.25 eV/species assuming democracy between the flavors). Furthermore, there is still the important issue of whether the neutrino and anti-neutrino are distinct particles (i.e. Dirac type) or not (Majorana type). The only way to answer both of these questions is through neutrinoless double beta decay (DBD) experiments. CUORE (Cryogenic Underground Observatory for Rare Events) is a …
Date: August 22, 2005
Creator: Norman, E B
Object Type: Article
System: The UNT Digital Library
Preliminary Field Evaluation of Mercury Control Using Combustion Modifications (open access)

Preliminary Field Evaluation of Mercury Control Using Combustion Modifications

In this project EER conducted a preliminary field evaluation of the integrated approach for mercury (Hg) and NO{sub x} control. The approach enhanced the 'naturally occurring' Hg capture by fly ash through combustion optimization, increasing carbon in ash content, and lowering ESP temperature. The evaluation took place in Green Station Units 1 and 2 located near Henderson, Kentucky and operated by Western Kentucky Energy. Units 1 and 2 are equipped with cold-side ESPs and wet scrubbers. Green Station Units 1 and 2 typically fire two types of fuel: a bituminous coal and a blend of bituminous coals based on availability. Testing of Hg emissions in Unit 2 without reburning system in operation and at minimum OFA demonstrated that efficiencies of Hg reduction downstream of the ESP were 30-40%. Testing also demonstrated that OFA system operation at 22% air resulted in 10% incremental increase in Hg removal efficiency at the ESP outlet. About 80% of Hg in flue gas at ESP outlet was present in the oxidized form. Testing of Hg emissions under reburning conditions showed that Hg emissions decreased with LOI increase and ESP temperature decrease. Testing demonstrated that maximum Hg reduction downstream of ESP was 40-45% at ESP temperatures …
Date: January 22, 2005
Creator: Lissianski, V.; Maly, P. & Marquez, T.
Object Type: Report
System: The UNT Digital Library
Produce More Oil and Gas via eBusiness Data Sharing (open access)

Produce More Oil and Gas via eBusiness Data Sharing

GWPC, DOGGR, and other state agencies propose to build eBusiness applications based on a .NET front-end user interface for the DOE's Energy 100 Award-winning Risk Based Data Management System (RBDMS) data source and XML Web services. This project will slash the costs of regulatory compliance by automating routine regulatory reporting and permit notice review and by making it easier to exchange data with the oil and gas industry--especially small, independent operators. Such operators, who often do not have sophisticated in-house databases, will be able to use a subset of the same RBDMS tools available to the agencies on the desktop to file permit notices and production reports online. Once the data passes automated quality control checks, the application will upload the data into the agency's RBDMS data source. The operators also will have access to state agency datasets to focus exploration efforts and to perform production forecasting, economic evaluations, and risk assessments. With the ability to identify economically feasible oil and gas prospects, including unconventional plays, over the Internet, operators will minimize travel and other costs. Because GWPC will coordinate these data sharing efforts with the Bureau of Land Management (BLM), this project will improve access to public lands and …
Date: July 22, 2005
Creator: Jehn, Paul; Stettner, Mike & Grunewald, Ben
Object Type: Report
System: The UNT Digital Library
Modeling Growth of Au-Cu Nanocrystalliine Coatings (open access)

Modeling Growth of Au-Cu Nanocrystalliine Coatings

The electrodeposition process parameters of current density, pulse duration, and cell potential affect both the structure and composition of the foils. The mechanism for nucleation and growth as determined from current transients yield relationships for nucleus density and nucleation rate. To develop an understanding of the role of the process parameters on grain size--as a design structural parameter to control strength, for example, a formulation is presented to model the affects of the deposition energetics on grain size and morphology. An activation energy for the deposition process is modeled that reveals different growth mechanisms, wherein nucleation and diffusion effects are each dominant as dependent upon pulse duration. A diffusion coefficient common for each of the pulsed growth modes demarcates an observed transition in growth from smooth to rough surfaces. Empirical relationships are developed that relate the parameters of the deposition process to the morphology and grain size at the nanoscale. Regimes for nanocrystalline growth include a short and long pulse mode, each with distinct activation energies. The long pulse has the additional contribution of bulk-like diffusion whereas the short pulse is limited to surface diffusion and nucleation. For either pulse condition, a transition from a rough (or nodular) growth to …
Date: September 22, 2005
Creator: Jankowski, Alan Frederic
Object Type: Article
System: The UNT Digital Library
Silicon-Germanium Films Deposited by Low Frequency PE CVD: Effect of H2 and Ar Dilution (open access)

Silicon-Germanium Films Deposited by Low Frequency PE CVD: Effect of H2 and Ar Dilution

We have studied structure and electrical properties of Si{sub 1-Y}Ge{sub Y}:H films deposited by low frequency PE CVD over the entire composition range from Y=0 to Y=1. The deposition rate of the films and their structural and electrical properties were measured for various ratios of the germane/silane feed gases and with and without dilution by Ar and by H{sub 2}. Structure and composition was studied by Auger electron spectroscopy (AES), secondary ion mass spectroscopy (SIMS) and Fourier transform infrared (FTIR) spectroscopy. Surface morphology was characterized by atomic force microscopy (AFM). We found: (1) The deposition rate increased with Y maximizing at Y=1 without dilution. (2) The relative rate of Ge and Si incorporation is affected by dilution. (3) Hydrogen preferentially bonds to silicon. (4) Hydrogen content decreases for increasing Y. In addition, optical measurements showed that as Y goes for 0 to 1, the Fermi level moves from mid gap to the conduction band edge, i.e. the films become more n-type. No correlation was found between the pre-exponential and the activation energy of conductivity. The behavior of the conductivity {gamma}-factor suggests a local minimum in the density of states at E {approx} 0.33 eV for the films grown with or …
Date: September 22, 2005
Creator: Kosarev, A; Torres, A; Hernandez, Y; Ambrosio, R; Zuniga, C; Felter, T E et al.
Object Type: Article
System: The UNT Digital Library
Cladding Degradation Summary for La (open access)

Cladding Degradation Summary for La

This report describes the Cladding Degradation Summary for La.
Date: February 22, 2005
Creator: W, Thomas Dennis
Object Type: Report
System: The UNT Digital Library
Mu B-Driven Electroweak Symmetry Breaking (open access)

Mu B-Driven Electroweak Symmetry Breaking

None
Date: September 22, 2005
Creator: Nomura, Yasunori; Poland, David & Tweedie, Brock
Object Type: Article
System: The UNT Digital Library
Remaining Sites Verification Package for 132-DR-1, 1608-DR Effluent Pumping Station, Waste Site Reclassification Form 2005-035 (open access)

Remaining Sites Verification Package for 132-DR-1, 1608-DR Effluent Pumping Station, Waste Site Reclassification Form 2005-035

Radiological characterization, decommissioning and demolition of the 132-DR-1 site, 1608-DR Effluent Pumping Station was performed in 1987. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. Residual concentrations support future land uses that can be represented by a rural-residential scenario and pose no threat to groundwater or the Columbia River based on RESRAD modeling.
Date: September 22, 2005
Creator: Carlson, R. A.
Object Type: Report
System: The UNT Digital Library
Safety Documentation for the M.I.C.E.2 Slot VLPC Cryocooler Cryostat (open access)

Safety Documentation for the M.I.C.E.2 Slot VLPC Cryocooler Cryostat

None
Date: March 22, 2005
Creator: Rucinski, Russell A.
Object Type: Report
System: The UNT Digital Library
Melanoma Therapy with Rhenium-Cyclized Alpha Melanocyte Stimulating Hormone Peptide Analogs (open access)

Melanoma Therapy with Rhenium-Cyclized Alpha Melanocyte Stimulating Hormone Peptide Analogs

Malignant melanoma is the 6th most commonly diagnosed cancer with increasing incidence in the United States. It is estimated that 54,200 cases of malignant melanoma will be newly diagnosed and 7,600 cases of death will occur in the United States in the year 2003 (1). At the present time, more than 1.3% of Americans will develop malignant melanoma during their lifetime (2). The average survival for patients with metastatic melanoma is about 6-9 months (3). Moreover, metastatic melanoma deposits are resistant to conventional chemotherapy and external beam radiation therapy (3). Systematic chemotherapy is the primary therapeutic approach to treat patients with metastatic melanoma. Dacarbazine is the only single chemotherapy agent approved by FDA for metastatic melanoma treatment (5). However, the response rate to Dacarbazine is only approximately 20% (6). Therefore, there is a great need to develop novel treatment approaches for metastatic melanoma. The global goal of this research program is the rational design, characterization and validation of melanoma imaging and therapeutic radiopharmaceuticals. Significant progress has been made in the design and characterization of metal-cyclized radiolabeled alpha-melanocyte stimulating hormone peptides. Therapy studies with {sup 188}Re-CCMSH demonstrated the therapeutic efficacy of the receptor-targeted treatment in murine and human melanoma bearing mice …
Date: November 22, 2005
Creator: Quinn, Thomas P.
Object Type: Report
System: The UNT Digital Library
Laboratory Directed Research and Development Program FY2004 (open access)

Laboratory Directed Research and Development Program FY2004

The Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab or LBNL) is a multi-program national research facility operated by the University of California for the Department of Energy (DOE). As an integral element of DOE's National Laboratory System, Berkeley Lab supports DOE's missions in fundamental science, energy resources, and environmental quality. Berkeley Lab programs advance four distinct goals for DOE and the nation: (1) To perform leading multidisciplinary research in the computing sciences, physical sciences, energy sciences, biosciences, and general sciences in a manner that ensures employee and public safety and protection of the environment. (2) To develop and operate unique national experimental facilities for qualified investigators. (3) To educate and train future generations of scientists and engineers to promote national science and education goals. (4) To transfer knowledge and technological innovations and to foster productive relationships among Berkeley Lab's research programs, universities, and industry in order to promote national economic competitiveness. Berkeley Lab's research and the Laboratory Directed Research and Development (LDRD) program support DOE's Strategic Goals that are codified in DOE's September 2003 Strategic Plan, with a primary focus on Advancing Scientific Understanding. For that goal, the Fiscal Year (FY) 2004 LDRD projects support every one of the …
Date: March 22, 2005
Creator: Hansen, Todd C.
Object Type: Report
System: The UNT Digital Library
Design For Six Sigma with Critical-To-Quality Metrics for Research Investments (open access)

Design For Six Sigma with Critical-To-Quality Metrics for Research Investments

Design for Six Sigma (DFSS) has evolved as a worthy predecessor to the application of Six-Sigma principles to production, process control, and quality. At Livermore National Laboratory (LLNL), we are exploring the interrelation of our current research, development, and design safety standards as they would relate to the principles of DFSS and Six-Sigma. We have had success in prioritization of research and design using a quantitative scalar metric for value, so we further explore the use of scalar metrics to represent the outcome of our use of the DFSS process. We use the design of an automotive component as an example of combining DFSS metrics into a scalar decision quantity. We then extend this concept to a high-priority, personnel safety example representing work that is toward the mature end of DFSS, and begins the transition into Six-Sigma for safety assessments in a production process. This latter example and objective involves the balance of research investment, quality control, and system operation and maintenance of high explosive handling at LLNL and related production facilities. Assuring a sufficiently low probability of failure (reaction of a high explosive given an accidental impact) is a Critical-To-Quality (CTQ) component of our weapons and stockpile stewardship operation …
Date: June 22, 2005
Creator: Logan, R W
Object Type: Report
System: The UNT Digital Library
Image Content Engine (ICE): A System for Fast Image Database Searches (open access)

Image Content Engine (ICE): A System for Fast Image Database Searches

The Image Content Engine (ICE) is being developed to provide cueing assistance to human image analysts faced with increasingly large and intractable amounts of image data. The ICE architecture includes user configurable feature extraction pipelines which produce intermediate feature vector and match surface files which can then be accessed by interactive relational queries. Application of the feature extraction algorithms to large collections of images may be extremely time consuming and is launched as a batch job on a Linux cluster. The query interface accesses only the intermediate files and returns candidate hits nearly instantaneously. Queries may be posed for individual objects or collections. The query interface prompts the user for feedback, and applies relevance feedback algorithms to revise the feature vector weighting and focus on relevant search results. Examples of feature extraction and both model-based and search-by-example queries are presented.
Date: March 22, 2005
Creator: Brase, J M; Paglieroni, D W; Weinert, G F; Grant, C W; Lopez, A S & Nikolaev, S
Object Type: Article
System: The UNT Digital Library
New Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cells (open access)

New Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cells

None
Date: February 22, 2005
Creator: Jacobson, Allan J.
Object Type: Report
System: The UNT Digital Library
Heat Transfer from Condensate Droplets Falling through an Immiscible Layer of Tributyl Phosphate (open access)

Heat Transfer from Condensate Droplets Falling through an Immiscible Layer of Tributyl Phosphate

As part of a safety analysis of reactions in two-layer mixtures of nitric acid and tributyl phosphate (TBP), an experiment was conducted to study how steam condensate mixes with the TBP layer when steam passes over a TBP-nitric acid mixture. The experiments showed that the condensate does not form a separate layer on top of the TBP but instead percolates as droplets through the TBP layer. The temperature at the top surface of the TBP layer undergoes a step change increase when the initial condensate droplets reach the surface. Temperatures at the surface and within the TBP and aqueous layers subsequently approach a steady state distribution governed by laminar convection and radiation heat transfer from the vapor space above the two-layer mixture. The rate of temperature increase and the steady state temperature gradient are determined by a characteristic propagation velocity and a streamwise dispersion coefficient for heat transfer. The propagation velocity is the geometric mean of the thermal convection velocities for the organic and aqueous phases, and the dispersion coefficient equals 0.494 times the product of the superficial condensate droplet velocity and the diameter of the test vessel. The value of the dispersion coefficient agrees with the Joshi (1980) correlation …
Date: August 22, 2005
Creator: Laurinat, James E.
Object Type: Article
System: The UNT Digital Library
Target Selection and Deselection at the Berkeley StructuralGenomics Center (open access)

Target Selection and Deselection at the Berkeley StructuralGenomics Center

At the Berkeley Structural Genomics Center (BSGC), our goalis to obtain a near-complete structural complement of proteins in theminimal organisms Mycoplasma genitalium and M. pneumoniae, two closelyrelated pathogens. Current targets for structure determination have beenselected in six major stages, starting with those predicted to be mosttractable to high throughput study and likely to yield new structuralinformation. We report on the process used to select these proteins, aswell as our target deselection procedure. Target deselection reducesexperimental effort by eliminating targets similar to those recentlysolved by the structural biology community or other centers. We measurethe impact of the 69 structures solved at the BSGC as of July 2004 onstructure prediction coverage of the M. pneumoniae and M. genitaliumproteomes. The number of Mycoplasma proteins for which thefold couldfirst be reliably assigned based on structures solved at the BSGC (24 M.pneumoniae and 21 M. genitalium) is approximately 25 percent of the totalresulting from work at all structural genomics centers and the worldwidestructural biology community (94 M. pneumoniae and 86M. genitalium)during the same period. As the number of structures contributed by theBSGC during that period is less than 1 percent of the total worldwideoutput, the benefits of a focused target selection strategy are apparent.If the …
Date: March 22, 2005
Creator: Chandonia, John-Marc; Kim, Sung-Hou & Brenner, Steven E.
Object Type: Article
System: The UNT Digital Library
Deep Borehole Instrumentation Along San Francisco Bay Bridges: 1996 - 2003 and Strong Ground Motion Systhesis Along the San Francisco/Oakland Bay Bridge (open access)

Deep Borehole Instrumentation Along San Francisco Bay Bridges: 1996 - 2003 and Strong Ground Motion Systhesis Along the San Francisco/Oakland Bay Bridge

As a result of collaboration between the Berkeley Seismographic Station, Lawrence Livermore National Laboratory, and Caltrans, instrument packages have been placed in bedrock in six boreholes and two surface sites along the San Francisco/Oakland Bay Bridge. Since 1996 over 200 local earthquakes have been recorded. Prior to this study few seismic recording instruments existed in bed-rock in San Francisco Bay. We utilized the data to perform analysis of ground motion variability, wave passage, site response, and up-and down-hole wave propagation along the Bay Bridge. We also synthesized strong ground motion at nine locations along the Bay Bridge. Key to these studies is LLNL's effort to exploit the information available in weak ground motions (generally from earthquakes < M=4.0) to enhance predictions of seismic hazards. We found that Yerba Island has no apparent site response at the surface relative to a borehole site. The horizontal to vertical spectral ratio method best revealed no site response, while the complex signal spectral ratio method had the lowest variance for spectral ratios and best predicted surface recordings when the borehole recording was used as input. Both methods identified resonances at about the same frequencies. Regional attenuation results in a significant loss of high frequencies …
Date: April 22, 2005
Creator: Hutchings, L; Foxall, W; Kasameyer, P; larsen, S; Hayek, C; Tyler-Turpin, C et al.
Object Type: Report
System: The UNT Digital Library
F-Canyon Sludge Physical Properties (open access)

F-Canyon Sludge Physical Properties

The Site Deactivation and Decommissioning (SDD) Organization is evaluating options to disposition the 800 underground tanks (including removal of the sludge heels from these tanks). To support this effort, D&D requested assistance from Savannah River National Laboratory (SRNL) personnel to determine the pertinent physical properties to effectively mobilize the sludge from these tanks (Tanks 804, 808, and 809). SDD provided SRNL with samples of the sludge from Tanks 804, 808, and 809. The authors measured the following physical properties for each tank: particle settling rate, shear strength (i.e., settled solids yield stress), slurry rheology (i.e., yield stress and consistency), total solids concentration in the sludge, soluble solids concentration of the sludge, sludge density, and particle size distribution.
Date: August 22, 2005
Creator: Poirier, M. R.; Hansen, P. R. & Fink, S. D.
Object Type: Report
System: The UNT Digital Library
Sixth International Conference on Systems Biology (ICSB 2005) (open access)

Sixth International Conference on Systems Biology (ICSB 2005)

This grant supported the Sixth International Conference on Systems Biology (ICSB 2005), held in Boston, Massachusetts from October 19th to 22nd, 2005. The ICSB is the only major, annual, international conference focused exclusively on the important emerging field of systems biology. It draws together scientists with expertise in theoretical, computational and experimental approaches to understanding biological systems at many levels. Previous ICSB meetings have been held in Tokyo (2000), at Caltech (2001), at the Karolinska Institute (2002), at Washington University in St. Louis (2003), and in Heidelberg (2004). These conferences have been increasingly successful at bringing together the growing community of established and junior researchers with interests in this area. Boston is home to several groups that have shown leadership in the field and was therefore an ideal place to hold this conference . The executive committee for the conference comprised Jim Collins (Biomedical Engineering, Boston University), Marc Kirschner (chair of the new Department of Systems Biology at Harvard Medical School), Eric Lander (director of the Broad Institute of MIT and Harvard), Andrew Murray (director of Harvard’s Bauer Center for Genomics Research) and Peter Sorger (director of MIT’s Computational and Systems Biology Initiative). There are almost as many definitions of …
Date: October 22, 2005
Creator: Murray, Professor Andrew
Object Type: Report
System: The UNT Digital Library
Saltstone Clean Cap Formulation (open access)

Saltstone Clean Cap Formulation

The current operation strategy for using Saltstone Vault 4 to receive 0.2 Ci/gallon salt solution waste involves pouring a clean grout layer over the radioactive grout prior to initiating pour into another cell. This will minimize the radiating surface area and reduce the dose rate at the vault and surrounding area. The Clean Cap will be used to shield about four feet of Saltstone poured into a Z-Area vault cell prior to moving to another cell. The minimum thickness of the Clean Cap layer will be determined by the cesium concentration and resulting dose levels and it is expected to be about one foot thick based on current calculations for 0.1 Ci Saltstone that is produced in the Saltstone process by stabilization of 0.2 Ci salt solution. This report documents experiments performed to identify a formulation for the Clean Cap. Thermal transient calculations, adiabatic temperature rise measurements, pour height, time between pour calculations and shielding calculations were beyond the scope and time limitations of this study. However, data required for shielding calculations (composition and specific gravity) are provided for shielding calculations. The approach used to design a Clean Cap formulation was to produce a slurry from the reference premix (10/45/45 …
Date: April 22, 2005
Creator: Langton, C
Object Type: Report
System: The UNT Digital Library
Implementing Information Security and Its Technology: A LineManagement Perspective (open access)

Implementing Information Security and Its Technology: A LineManagement Perspective

Assuring the security and privacy of institutionalinformation assets is a complex task for the line manager responsible forinternational and multi-national transactions. In the face of an unsureand often conflicting international legal framework, the line managermust employ all available tools in an Integrated Security and PrivacyManagement framework that ranges from legal obligations, to policy, toprocedure, to cutting edge technology to counter the rapidly evolvingcyber threat to information assets and the physical systems thatinformation systems control.
Date: August 22, 2005
Creator: Barletta, William A.
Object Type: Article
System: The UNT Digital Library
Material-dependent high-frequency current fluctuations of cathodicvacuum arcs: Evidence for the ecton cutoff of the fractal model (open access)

Material-dependent high-frequency current fluctuations of cathodicvacuum arcs: Evidence for the ecton cutoff of the fractal model

Current fluctuations of cathodic arcs were recorded withhigh analog bandwidth (up to 1 GHz) and fast digital sampling (up to 5Gsamples/sec). The power spectral density of the arc current wasdetermined by fast Fourier transform clearly showing material dependent,non-linear features in the frequency domain. These features can beassociated with the non-linear impedance of the conducting channelbetween cathode and anode, driven by the explosive nature of electronemission and plasma formation. The characteristic times of less than 100ns can be associated with individual explosive processes, "ectons," andtherefore represent the short-time physical cutoff for the fractal modelof cathodic arcs.
Date: December 22, 2005
Creator: Anders, Andre & Oks, Efim
Object Type: Article
System: The UNT Digital Library
Test Bed for Superconducting Materials (open access)

Test Bed for Superconducting Materials

Superconducting rf cavities are increasingly used in accelerators. Gradient is a parameter of particular importance for the ILC. Much progress in gradient has been made over the past decade, overcoming problems of multipacting, field emission, and breakdown triggered by surface impurities. However, the quenching limit of the surface magnetic field for niobium remains a hard limitation on cavity fields sustainable with this technology. Further exploration of materials and preparation may offer a path to surpassing the current limit. For this purpose, we have designed a resonant test cavity. One wall of the cavity is formed by a flat sample of superconducting material; the rest of the cavity is copper or niobium. The H field on the sample wall is 75% higher than on any other surface. Multipacting is avoided by use of a mode with no surface electric field. The cavity will be resonated through a coupling iris with high-power rf at superconducting temperature until the sample wall quenches, as detected by a change in the quality factor. This experiment will allow us to measure critical magnetic fields up to well above that of niobium with minimal cost and effort.
Date: June 22, 2005
Creator: Nantista, C.; Tantawi, S.; Weisend, J.; Siemann, R. & Dolgashev, V.
Object Type: Article
System: The UNT Digital Library