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National Digital Stewardship Alliance Web Archiving Survey Report: 2012 (open access)

National Digital Stewardship Alliance Web Archiving Survey Report: 2012

The National Digital Stewardship Alliance is a member organization whose mission is to establish, maintain, and advance the capacity to preserve our nation's digital resources for the benefit of present and future generations. From October 3 through October 31, 2011, the Content Working Group conducted a survey of organizations in the United States that are actively involved in, or planning to start, programs to archive content from the web. The goal of the survey was to better understand the landscape of web archiving activities in the United States, including identifying the organizations or individuals involved, the types of web content being preserved, the tools and services being used, and the types of access being provided. This summary report examines participant responses for the purposes of discerning trends, themes, and emerging practices and challenges in web-based content acquisition and preservation.
Date: June 19, 2012
Creator: National Digital Stewardship Alliance (U.S.)
System: The UNT Digital Library
Numerical Modeling of 90Sr and 137Cs Transport from a Spill in the B-Cell of the 324 Building, Hanford Site 300 Area (open access)

Numerical Modeling of 90Sr and 137Cs Transport from a Spill in the B-Cell of the 324 Building, Hanford Site 300 Area

To characterize the extent of contamination under the 324 Building, a pit was excavated on the north side of the building in 2010 by Washington Closure Hanford LLC (WCH). Horizontal closed-end steel access pipes were installed under the foundation of the building from this pit and were used for measuring temperatures and exposure rates under the B-Cell. The deployed sensors measured elevated temperatures of up to 61 C (142 F) and exposure rates of up to 8,900 R/hr. WCH suspended deactivation of the facility because it recognized that building safety systems and additional characterization data might be needed for remediation of the contaminated material. The characterization work included additional field sampling, laboratory measurements, and numerical flow and transport modeling. Laboratory measurements of sediment physical, hydraulic, and geochemical properties were performed by Pacific Northwest National Laboratory (PNNL) and others. Geochemical modeling and subsurface flow and transport modeling also were performed by PNNL to evaluate the possible extent of contamination in the unsaturated sand and gravel sediments underlying the building. Historical records suggest that the concentrated 137Cs- and 90Sr-bearing liquid wastes that were spilled in B-Cell were likely from a glass-waste repository testing program associated with the Federal Republic of Germany (FRG). …
Date: March 19, 2012
Creator: Rockhold, Mark L.; Bacon, Diana H.; Freedman, Vicky L.; Lindberg, Michael J. & Clayton, Ray E.
System: The UNT Digital Library
National Emission Standards for Hazardous Air Pollutants - Radionuclide Emissions, Calendar Year 2011 (open access)

National Emission Standards for Hazardous Air Pollutants - Radionuclide Emissions, Calendar Year 2011

The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office operates the Nevada National Security Site (NNSS) and North Las Vegas Facility (NLVF). From 1951 through 1992, the NNSS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NNSS activities has been monitored since the initiation of atmospheric testing. Limitation to underground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NNSS. After nuclear testing ended in 1992, NNSS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by wind) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of legacy-related tritium are also emitted to air at the NLVF, an NNSS support complex in North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations [CFR] Part 61 Subpart H) limits the release of radioactivity from a U.S. Department of Energy (DOE) facility to that which would cause 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include …
Date: June 19, 2012
Creator: Monitoring, NSTec Ecological and Environmental
System: The UNT Digital Library
Parametric Explosion Spectral Model (open access)

Parametric Explosion Spectral Model

Small underground nuclear explosions need to be confidently detected, identified, and characterized in regions of the world where they have never before occurred. We develop a parametric model of the nuclear explosion seismic source spectrum derived from regional phases that is compatible with earthquake-based geometrical spreading and attenuation. Earthquake spectra are fit with a generalized version of the Brune spectrum, which is a three-parameter model that describes the long-period level, corner-frequency, and spectral slope at high-frequencies. Explosion spectra can be fit with similar spectral models whose parameters are then correlated with near-source geology and containment conditions. We observe a correlation of high gas-porosity (low-strength) with increased spectral slope. The relationship between the parametric equations and the geologic and containment conditions will assist in our physical understanding of the nuclear explosion source.
Date: January 19, 2012
Creator: Ford, S R & Walter, W R
System: The UNT Digital Library
Scotts Valley Band of Pomo Indians First Steps Toward Tribal Weatherization - Human Capacity Development (open access)

Scotts Valley Band of Pomo Indians First Steps Toward Tribal Weatherization - Human Capacity Development

The objectives of this project are to create jobs and to provide tribal homes and buildings with weatherization assistance for energy efficiency. The project will establish a Tribal Multi-County Weatherization Energy Program to provide training, outreach and education on energy assistance and conservation to low-income families. The Tribes' mission, under its Strategic Energy Plan of 2008, is to promote tribal efficiency, reduce energy costs, create jobs, economic opportunities, and incorporate energy planning in construction and economic development.
Date: June 19, 2012
Creator: Ray, Irenia Quitiquit Gabriel
System: The UNT Digital Library
Emerging Technologies and Approaches to Minimize Discharges Into Lake Michigan, Phase 2 Module 4 Report. (open access)

Emerging Technologies and Approaches to Minimize Discharges Into Lake Michigan, Phase 2 Module 4 Report.

The Great Lakes Initiative (GLI) established the new water quality-based discharge criteria for mercury (Hg), thereby increasing the need for many municipal and industrial wastewater treatment plants in the region to lower the mercury in their effluents. Information on deployable technologies to satisfy these requirements for industrial and municipal dischargers in the Great lakes region is scarce. Therefore, BP funded Purdue University Calumet and Argonne to identify deployable Hg removal technologies to meet the GLI discharge criterion at its Whiting Refinery in Indiana. The joint PUC/Argonne project was divided into 2 phases. Results from Phase I and Phase II Modules 1-3 have been previously reported. This report summarizes the work done in Phase 3 Module 4, which consisted of the pilot scale testing of Hg removal technologies previously selected in Module 3. The pilot testing was an Argonne/PUC jointly directed project that was hosted at and funded by the BP refinery in Whiting, IN. As two organizations were involved in data analysis and interpretation, this report combines two independent sets of evaluations of the testing that was done, prepared respectively by Argonne and Purdue. Each organization retains sole responsibility for its respective analysis conclusions and recommendations. Based on Module 3 …
Date: April 19, 2012
Creator: Negri, M.C.; Gillenwater, P.; Urgun-Demirtas, M.; Nnanna, G.; Yu, J.; Jannotta, I, (Energy Systems) et al.
System: The UNT Digital Library
Upgrade scenario for the RHIC collimation system (open access)

Upgrade scenario for the RHIC collimation system

The RHIC collimation system is used to reduce background levels in both STAR and PHENIX detectors. With a push for higher luminosity in the near future, it becomes critical to check if and how the level of performance of the collimators can be improved. The following reviews a proposal for additional collimators placed further downstream of the current system and designed to intercept the tertiary halo coming out of the IR8 insertion before it can reach the triplet quadrupoles in either STAR or PHENIX. Simulations have been peformed to quantify the efficiency of additional collimator jaws in RHIC. Each figure presented in this article clearly shows that the additional mask collimators provide the expected reduction in losses around the machine, and especially to the incoming triplet to the STAR experiment (IP6), for the Yellow beam as much as for the Blue beam. Looking at compiled statistics for all three working point cases studied, proton losses around the machine are reduced by roughly one order of magnitude: at most a factor 30 for magnet losses, and at most a factor 40 for losses in spaces between magnets.
Date: January 19, 2012
Creator: G., Robert-Demolaize; Drees&#44 & A.
System: The UNT Digital Library
DX magnet requirements for p-Au operation (open access)

DX magnet requirements for p-Au operation

This document addresses the question of moving the DX magnets for p-Au operations. First the beam geometry is addressed. Next, the beam sizes are covered. Finally, a conclusion is presented.
Date: January 19, 2012
Creator: Tepikian, S.; Trbojevic&#44 & D.
System: The UNT Digital Library
TEST PLAN AND PROCEDURE FOR THE EXAMINATION OF TANK 241-AY-101 MULTI-PROBE CORROSION MONITORING SYSTEM (open access)

TEST PLAN AND PROCEDURE FOR THE EXAMINATION OF TANK 241-AY-101 MULTI-PROBE CORROSION MONITORING SYSTEM

This test plan describes the methods to be used in the forensic examination of the Multi-probe Corrosion Monitoring System (MPCMS) installed in the double-shell tank 241-AY-101 (AY-101). The probe was designed by Applied Research and Engineering Sciences (ARES) Corporation. The probe contains four sections, each of which can be removed from the tank independently (H-14-107634, AY-101 MPCMS Removable Probe Assembly) and one fixed center assembly. Each removable section contains three types of passive corrosion coupons: bar coupons, round coupons, and stressed C-rings (H-14-l07635, AY-101 MPCMS Details). Photographs and weights of each coupon were recorded and reported on drawing H-14-107634 and in RPP-RPT-40629, 241-AY-101 MPCMS C-Ring Coupon Photographs. The coupons will be the subject of the forensic analyses. The purpose of this examination will be to document the nature and extent of corrosion of the 29 coupons. This documentation will consist of photographs and photomicrographs of the C-rings and round coupons, as well as the weights of the bar and round coupons during corrosion removal. The total weight loss of the cleaned coupons will be used in conjunction with the surface area of each to calculate corrosion rates in mils per year. The bar coupons were presumably placed to investigate the …
Date: April 19, 2012
Creator: Wyrwas, R. B.; Page, J. S. & Cooke, G. S.
System: The UNT Digital Library
Commercial Building Energy Asset Rating Program -- Market Research (open access)

Commercial Building Energy Asset Rating Program -- Market Research

Under contract to Pacific Northwest National Laboratory, HaydenTanner, LLC conducted an in-depth analysis of the potential market value of a commercial building energy asset rating program for the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy. The market research objectives were to: (1) Evaluate market interest and need for a program and tool to offer asset rating and rapidly identify potential energy efficiency measures for the commercial building sector. (2) Identify key input variables and asset rating outputs that would facilitate increased investment in energy efficiency. (3) Assess best practices and lessons learned from existing national and international energy rating programs. (4) Identify core messaging to motivate owners, investors, financiers, and others in the real estate sector to adopt a voluntary asset rating program and, as a consequence, deploy high-performance strategies and technologies across new and existing buildings. (5) Identify leverage factors and incentives that facilitate increased investment in these buildings. To meet these objectives, work consisted of a review of the relevant literature, examination of existing and emergent asset and operational rating systems, interviews with industry stakeholders, and an evaluation of the value implication of an asset label on asset valuation. This report documents the …
Date: April 19, 2012
Creator: McCabe, Molly J. & Wang, Na
System: The UNT Digital Library
Environmentally Benign and Permanent Modifications to Prevent Biofouling on Marine and Hydrokinetic Devices (open access)

Environmentally Benign and Permanent Modifications to Prevent Biofouling on Marine and Hydrokinetic Devices

Semprus Biosciences is developing environmentally benign and permanent modifications to prevent biofouling on Marine and Hydrokinetic (MHK) devices. Biofouling, including growth on external surfaces by bacteria, algae, barnacles, mussels, and other marine organisms, accumulate quickly on MHK devices, causing mechanical wear and changes in performance. Biofouling on crucial components of hydrokinetic devices, such as rotors, generators, and turbines, imposes substantial mass and hydrodynamic loading with associated efficiency loss and maintenance costs. Most antifouling coatings leach toxic ingredients, such as copper and tributyltin, through an eroding process, but increasingly stringent regulation of biocides has led to interest in the development of non-biocidal technologies to control fouling. Semprus Biosciences research team is developing modifications to prevent fouling from a broad spectrum of organisms on devices of all shapes, sizes, and materials for the life of the product. The research team designed and developed betaine-based polymers as novel underwater coatings to resist the attachment of marine organisms. Different betaine-based monomers and polymers were synthesized and incorporated within various coating formulations. The formulations and application methods were developed on aluminum panels with required adhesion strength and mechanical properties. The coating polymers were chemically stable under UV, hydrolytic and oxidative environments. The sulfobetaine formulations are …
Date: April 19, 2012
Creator: Zhang, Zheng
System: The UNT Digital Library
Low Dose Radiation Cancer Risks: Epidemiological and Toxicological Models (open access)

Low Dose Radiation Cancer Risks: Epidemiological and Toxicological Models

The basic purpose of this one year research grant was to extend the two stage clonal expansion model (TSCE) of carcinogenesis to exposures other than the usual single acute exposure. The two-stage clonal expansion model of carcinogenesis incorporates the biological process of carcinogenesis, which involves two mutations and the clonal proliferation of the intermediate cells, in a stochastic, mathematical way. The current TSCE model serves a general purpose of acute exposure models but requires numerical computation of both the survival and hazard functions. The primary objective of this research project was to develop the analytical expressions for the survival function and the hazard function of the occurrence of the first cancer cell for acute, continuous and multiple exposure cases within the framework of the piece-wise constant parameter two-stage clonal expansion model of carcinogenesis. For acute exposure and multiple exposures of acute series, it is either only allowed to have the first mutation rate vary with the dose, or to have all the parameters be dose dependent; for multiple exposures of continuous exposures, all the parameters are allowed to vary with the dose. With these analytical functions, it becomes easy to evaluate the risks of cancer and allows one to deal …
Date: April 19, 2012
Creator: David G. Hoel, PhD
System: The UNT Digital Library
Using a Neural Network to Determine the Hatch Status of the AERI at the ARM North Slope of Alaska Site (open access)

Using a Neural Network to Determine the Hatch Status of the AERI at the ARM North Slope of Alaska Site

The fore-optics of the Atmospheric Emitted Radiance Interferometer (AERI) are protected by an automated hatch to prevent precipitation from fouling the instrument's scene mirror (Knuteson et al. 2004). Limit switches connected with the hatch controller provide a signal of the hatch state: open, closed, undetermined (typically associated with the hatch being between fully open or fully closed during the instrument's sky view period), or an error condition. The instrument then records the state of the hatch with the radiance data so that samples taken when the hatch is not open can be removed from any subsequent analysis. However, the hatch controller suffered a multi-year failure for the AERI located at the ARM North Slope of Alaska (NSA) Central Facility in Barrow, Alaska, from July 2006-February 2008. The failure resulted in misreporting the state of the hatch in the 'hatchOpen' field within the AERI data files. With this error there is no simple solution to translate what was reported back to the correct hatch status, thereby making it difficult for an analysis to determine when the AERI was actually viewing the sky. As only the data collected when the hatch is fully open are scientifically useful, an algorithm was developed to …
Date: March 19, 2012
Creator: Zwink, A. B. & Turner, D. D.
System: The UNT Digital Library
What Have we Learned from the LCLS Injector? (open access)

What Have we Learned from the LCLS Injector?

The LCLS injector reliably delivered a high quality electron beam since it started operations three years ago. Some initial commissioning results were described in Ref. [1]. This note is to summarize what we have understood from the LCLS injector including drive laser, cathode, RF gun, injector beam line elements, beam modeling and operations. What we have learned during the LCLS injector commissioning and operation has lead to modified specifications for the UV drive laser system. A flat temporal profile originally required in the LCLS design is not necessary to achieve a low emittance electron beam for the LCLS operations. According to our recent studies, a laser pulse with 3 ps Gaussian temporal profile (FWHM) can achieve a similar emittance compared to a flat temporal profile laser. The sensitivity of the emittance to the laser pulse length at 250 pC of bunch charge was studied, as shown in Figure 1. Only slight variations were observed for both projected and time-sliced emittances with laser pulses from 2.2 ps to 4.5 ps FWHM. Space charge forces certainly become weak but RF emittance which is proportional to the bunch length square increases due to the longer laser pulse. Thus, the projected emittance optimum may …
Date: March 19, 2012
Creator: Zhou, Feng & Brachmann, Axel
System: The UNT Digital Library
Energy Saving Melting and Revert Reduction Technology: Aging of Graphitic Cast Irons and Machinability (open access)

Energy Saving Melting and Revert Reduction Technology: Aging of Graphitic Cast Irons and Machinability

The objective of this task was to determine whether ductile iron and compacted graphite iron exhibit age strengthening to a statistically significant extent. Further, this effort identified the mechanism by which gray iron age strengthens and the mechanism by which age-strengthening improves the machinability of gray cast iron. These results were then used to determine whether age strengthening improves the machinability of ductile iron and compacted graphite iron alloys in order to develop a predictive model of alloy factor effects on age strengthening. The results of this work will lead to reduced section sizes, and corresponding weight and energy savings. Improved machinability will reduce scrap and enhance casting marketability. Technical Conclusions: • Age strengthening was demonstrated to occur in gray iron ductile iron and compacted graphite iron. • Machinability was demonstrated to be improved by age strengthening when free ferrite was present in the microstructure, but not in a fully pearlitic microstructure. • Age strengthening only occurs when there is residual nitrogen in solid solution in the Ferrite, whether the ferrite is free ferrite or the ferrite lamellae within pearlite. • Age strengthening can be accelerated by Mn at about 0.5% in excess of the Mn/S balance Estimated energy savings …
Date: September 19, 2012
Creator: Richards, Von L.
System: The UNT Digital Library
Summary of operations and performance of the Utica aquifer and North Lake Basin Wetlands restoration project in December 2010-November 2011. (open access)
Fast Pyrolysis Oil Stabilization: An Integrated Catalytic and Membrane Approach for Improved Bio-oils (open access)

Fast Pyrolysis Oil Stabilization: An Integrated Catalytic and Membrane Approach for Improved Bio-oils

This University of Massachusetts, Amherst project, "Fast Pyrolysis Oil Stabilization: An Integrated Catalytic and Membrane Approach for Improved Bio-oils" started on 1st February 2009 and finished on August 31st 2011. The project consisted following tasks: Task 1.0: Char Removal by Membrane Separation Technology The presence of char particles in the bio-oil causes problems in storage and end-use. Currently there is no well-established technology to remove char particles less than 10 micron in size. This study focused on the application of a liquid-phase microfiltration process to remove char particles from bio-oil down to slightly sub-micron levels. Tubular ceramic membranes of nominal pore sizes 0.5 and 0.8 µm were employed to carry out the microfiltration, which was conducted in the cross-flow mode at temperatures ranging from 38 to 45 C and at three different trans-membrane pressures varying from 1 to 3 bars. The results demonstrated the removal of the major quantity of char particles with a significant reduction in overall ash content of the bio-oil. The results clearly showed that the cake formation mechanism of fouling is predominant in this process. Task 2.0 Acid Removal by Membrane Separation Technology The feasibility of removing small organic acids from the aqueous fraction of fast …
Date: October 19, 2012
Creator: \Huber, George W.; Upadhye, Aniruddha A.; Ford, David M.; Bhatia, Surita R. & Badger, Phillip C.
System: The UNT Digital Library
CHARACTERIZATION OF TANK 16H ANNULUS SAMPLES PART II: LEACHING RESULTS (open access)

CHARACTERIZATION OF TANK 16H ANNULUS SAMPLES PART II: LEACHING RESULTS

The closure of Tank 16H will require removal of material from the annulus of the tank. Samples from Tank 16H annulus were characterized and tested to provide information to evaluate various alternatives for removing the annulus waste. The analysis found all four annulus samples to be composed mainly of Si, Na, and Al and lesser amounts of other elements. The XRD data indicate quartz (SiO{sub 2}) and sodium aluminum nitrate silicate hydrate (Na{sub 8}(Al{sub 6}Si{sub 6}O{sub 24})(NO{sub 3}){sub 2}.4H{sub 2}O) as the predominant crystalline mineral phases in the samples. The XRD data also indicate the presence of crystalline sodium nitrate (NaNO{sub 3}), sodium nitrite (NaNO{sub 2}), gibbsite (Al(OH){sub 3}), hydrated sodium bicarbonate (Na{sub 3}H(CO{sub 3}){sub 2}.2H{sub 2}O), and muscovite (KAl{sub 2}(AlSi{sub 3}O{sub 10})(OH){sub 2}). Based on the weight of solids remaining at the end of the test, the water leaching test results indicate 20-35% of the solids dissolved after three contacts with an approximately 3:1 volume of water at 45 C. The chemical analysis of the leachates and the XRD results of the remaining solids indicate sodium salts of nitrate, nitrite, sulfate, and possibly carbonate/bicarbonate make up the majority of the dissolved material. The majority of these salts were dissolved …
Date: June 19, 2012
Creator: Hay, M. & Reboul, S.
System: The UNT Digital Library
High-Power Microwave Switch Employing Electron Beam Triggering (open access)

High-Power Microwave Switch Employing Electron Beam Triggering

A high-power active microwave pulse compressor is described that modulates the quality factor Q of the energy storage cavity by a new means involving mode conversion controlled by a triggered electron-beam discharge through a switch cavity. The electron beam is emitted from a diamond-coated molybdenum cathode. This report describes the principle of operation, the design of the switch, the configuration used for the test, and the experimental results. The pulse compressor produced output pulses with 140 - “165 MW peak power, power gain of 16 - 20, and pulse duration of 16 - 20 ns at a frequency of 11.43 GHz.
Date: September 19, 2012
Creator: Hirshfield, Jay L.
System: The UNT Digital Library
WBN-1 Cycle 10 TPBAR Tritium Release, Deduced From Analysis of RCS Data TTP-1-3046-00, Rev 0 (open access)

WBN-1 Cycle 10 TPBAR Tritium Release, Deduced From Analysis of RCS Data TTP-1-3046-00, Rev 0

This document contains the calculation of the TPBAR tritium release from the Mark 9.2 design TPBARs irradiated in WBN cycle 10. The calculation utilizes the generalized cycle analysis methodology given in TTP-1-3045 Rev. 0.
Date: February 19, 2012
Creator: Shaver, Mark W.; Niehus, Mark T. & Love, Edward F.
System: The UNT Digital Library
Integrated Detection of Pathogens and Host Biomarkers for Wounds (open access)

Integrated Detection of Pathogens and Host Biomarkers for Wounds

The increasing incidence and complications arising from combat wounds has necessitated a reassessment of methods for effective treatment. Infection, excessive inflammation, and incidence of drug-resistant organisms all contribute toward negative outcomes for afflicted individuals. The organisms and host processes involved in wound progression, however, are incompletely understood. We therefore set out, using our unique technical resources, to construct a profile of combat wounds which did or did not successfully resolve. We employed the Lawrence Livermore Microbial Detection Array and identified a number of nosocomial pathogens present in wound samples. Some of these identities corresponded with bacterial isolates previously cultured, while others were not obtained via standard microbiology. Further, we optimized proteomics protocols for the identification of host biomarkers indicative of various stages in wound progression. In combination with our pathogen data, our biomarker discovery efforts will provide a profile corresponding to wound complications, and will assist significantly in treatment of these complex cases.
Date: March 19, 2012
Creator: Jaing, C
System: The UNT Digital Library
Final Work Plan: ISCR Pilot Test at Montgomery City, Missouri. (open access)

Final Work Plan: ISCR Pilot Test at Montgomery City, Missouri.

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Date: November 19, 2012
Creator: LaFreniere, L. M.
System: The UNT Digital Library
Interim Report on the Optimization and Feasibility Studies for the Neutron Detection without Helium-3 Project (open access)

Interim Report on the Optimization and Feasibility Studies for the Neutron Detection without Helium-3 Project

This report provides the status and results of the first year's effort in modeling and simulation to investigate alternatives to helium-3 for neutron detection in safeguards applications.
Date: March 19, 2012
Creator: Ely, James H.
System: The UNT Digital Library
Characteristics of Short Wavelength Compressional Alfven Eigenmodes (open access)

Characteristics of Short Wavelength Compressional Alfven Eigenmodes

Most Alfvenic activity in the frequency range between Toroidal Alfven Eigenmodes and roughly one half of the ion cyclotron frequency on NSTX [M. Ono, et al., Nucl. Fusion 40 (2000) 557], that is, approximately 0.3 MHz up to ≈ 1.2 MHz, are modes propagating counter to the neutral beam ions. These have been modeled as Compressional and Global Alfven Eigenmodes (CAE and GAE) and are excited through a Doppler-shifted cyclotron resonance with the beam ions. There is also a class of co-propagating modes at higher frequency than the counter-propagating CAE and GAE. These modes have been identified as CAE, and are seen mostly in the company of a low frequency, n=1 kink-like mode. In this paper we present measurements of the spectrum of these high frequency CAE (hfCAE), and their mode structure. We compare those measurements to a simple model of CAE and present evidence of a curious non-linear coupling of the hfCAE and the low frequency kink-like mode.
Date: December 19, 2012
Creator: Fredrickson, E. D.; Podesta, M.; Bortolon, A.; Crocker, N. A.; Gerhardt, S. P.; Bell, R. E. et al.
System: The UNT Digital Library