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Measurements of the Persistent Current Decay and Snapback Effect in Nb3Sn Accelerator Prototype Magnets at Fermilab (open access)

Measurements of the Persistent Current Decay and Snapback Effect in Nb3Sn Accelerator Prototype Magnets at Fermilab

None
Date: May 1, 2012
Creator: Velev, G.V.; Chlachidze, G.; DiMarco, J.; Kashikhin, V.V. & /Fermilab
Object Type: Article
System: The UNT Digital Library
Coalescing at 8 GeV in the Fermilab Main Injector (open access)

Coalescing at 8 GeV in the Fermilab Main Injector

For Project X, it is planned to inject a beam of 3 10{sup 11} particles per bunch into the Main Injector. To prepare for this by studying the effects of higher intensity bunches in the Main Injector it is necessary to perform coalescing at 8 GeV. The results of a series of experiments and simulations of 8 GeV coalescing are presented. To increase the coalescing efficiency adiabatic reduction of the 53 MHz RF is required. This results in {approx}70% coalescing efficiency of 5 initial bunches. Data using wall current monitors has been taken to compare previous work and new simulations for 53 MHz RF reduction, bunch rotations and coalescing, good agreement between experiment and simulation was found. By increasing the number of bunches to 7 and compressing the bunch energy spread a scheme generating approximately 3 10{sup 11} particles in a bunch has been achieved. These bunches will then be used in further investigations.
Date: May 1, 2012
Creator: Scott, D. J.; Capista, D.; Chase, B.; Dye, J.; Kourbanis, I.; Seiya, K. et al.
Object Type: Article
System: The UNT Digital Library
Single/Few Bunch Space Charge Effects at 8 GeV in the Fermilab Main Injector (open access)

Single/Few Bunch Space Charge Effects at 8 GeV in the Fermilab Main Injector

For Project X, it is planned to inject a beam of 3 10{sup 11} particles per bunch into the Main Injector. Therefore, at 8 GeV, there will be increased space charge tune shifts and an increased incoherent tune spread. In preparation for these higher intensity bunches exploratory studies have commenced looking at the transmission of different intensity bunches at different tunes. An experiment is described with results for bunch intensities between 20 and 300 10{sup 9} particles. To achieve the highest intensity bunches coalescing at 8 GeV is required, resulting in a longer bunch length. Comparisons show that similar transmission curves are obtained when the intensity and bunch length have increased by similar factors. This indicates the incoherent tune shifts are similar, as expected from theory. The results of these experiments will be used in conjugation with simulations to further study high intensity bunches in the Main Injector.
Date: May 1, 2012
Creator: Scott, D. J.; Capista, D.; Kourbanis, I.; Seiya, K. & Yang, M. J.
Object Type: Article
System: The UNT Digital Library
Covariant nucleon wave function with S, D, and P-state components (open access)

Covariant nucleon wave function with S, D, and P-state components

Expressions for the nucleon wave functions in the covariant spectator theory (CST) are derived. The nucleon is described as a system with a off-mass-shell constituent quark, free to interact with an external probe, and two spectator constituent quarks on their mass shell. Integrating over the internal momentum of the on-mass-shell quark pair allows us to derive an effective nucleon wave function that can be written only in terms of the quark and diquark (quark-pair) variables. The derived nucleon wave function includes contributions from S, P and D-waves.
Date: May 1, 2012
Creator: Franz Gross, G. Ramalho, M. T. Pena
Object Type: Article
System: The UNT Digital Library
Building America Spring 2012 Stakeholder Meeting Report - Austin, Texas: February 29 - March 2, 2012 (open access)

Building America Spring 2012 Stakeholder Meeting Report - Austin, Texas: February 29 - March 2, 2012

This document is no longer available. Please contact Cheryn.Metzger@nrel.gov for further information.
Date: May 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Sequestration and Enhanced Coal Bed Methane: Tanquary Farms Test Site, Wabash County, Illinois (open access)

Sequestration and Enhanced Coal Bed Methane: Tanquary Farms Test Site, Wabash County, Illinois

The Midwest Geological Sequestration Consortium (MGSC) carried out a pilot project to test storage of carbon dioxide (CO{sub 2}) in the Springfield Coal Member of the Carbondale Formation (Pennsylvanian System), in order to gauge the potential for large-scale CO{sub 2} sequestration and/or enhanced coal bed methane recovery from Illinois Basin coal beds. The pilot was conducted at the Tanquary Farms site in Wabash County, southeastern Illinois. A four-well design— an injection well and three monitoring wells—was developed and implemented, based on numerical modeling and permeability estimates from literature and field data. Coal cores were taken during the drilling process and were characterized in detail in the lab. Adsorption isotherms indicated that at least three molecules of CO{sub 2} can be stored for each displaced methane (CH{sub 4}) molecule. Microporosity contributes significantly to total porosity. Coal characteristics that affect sequestration potential vary laterally between wells at the site and vertically within a given seam, highlighting the importance of thorough characterization of injection site coals to best predict CO{sub 2} storage capacity. Injection of CO{sub 2} gas took place from June 25, 2008, to January 13, 2009. A “continuous” injection period ran from July 21, 2008, to December 23, 2008, but injection …
Date: May 1, 2012
Creator: Frailey, Scott; Parris, Thomas; Damico, James; Okwen, Roland; McKaskle, Ray; Monson, Charles et al.
Object Type: Report
System: The UNT Digital Library
Secondary Electron Yield Measurements of Fermilab's Main Injector Vacuum Vessel (open access)

Secondary Electron Yield Measurements of Fermilab's Main Injector Vacuum Vessel

We discuss the progress made on a new installation in Fermilab's Main Injector that will help investigate the electron cloud phenomenon by making direct measurements of the secondary electron yield (SEY) of samples irradiated in the accelerator. In the Project X upgrade the Main Injector will have its beam intensity increased by a factor of three compared to current operations. This may result in the beam being subject to instabilities from the electron cloud. Measured SEY values can be used to further constrain simulations and aid our extrapolation to Project X intensities. The SEY test-stand, developed in conjunction with Cornell and SLAC, is capable of measuring the SEY from samples using an incident electron beam when the samples are biased at different voltages. We present the design and manufacture of the test-stand and the results of initial laboratory tests on samples prior to installation.
Date: May 1, 2012
Creator: Scott, D. J.; Capista, D.; Duel, K. L.; Zwaska, R. M.; Greenwald, S.; Hartung, W. et al.
Object Type: Article
System: The UNT Digital Library
Influence of Intense Beam in High Pressure Hydrogen Gas Filled RF Cavities (open access)

Influence of Intense Beam in High Pressure Hydrogen Gas Filled RF Cavities

The influence of an intense beam in a high-pressure gas filled RF cavity has been measured by using a 400 MeV proton beam in the Mucool Test Area at Fermilab. The ionization process generates dense plasma in the cavity and the resultant power loss to the plasma is determined by measuring the cavity voltage on a sampling oscilloscope. The energy loss has been observed with various peak RF field gradients (E), gas pressures (p), and beam intensities in nitrogen and hydrogen gases. Observed RF energy dissipation in single electron (dw) in N{sub 2} and H{sub 2} gases was 2 10{sup -17} and 3 10{sup -17} Joules/RF cycle at E/p = 8 V/cm/Torr, respectively. More detailed dw measurement have been done in H{sub 2} gas at three different gas pressures. There is a clear discrepancy between the observed dw and analytical one. The discrepancy may be due to the gas density effect that has already been observed in various experiments.
Date: May 1, 2012
Creator: Yonehara, K.; Chung, M.; Collura, M. G.; Jana, M. R.; Leonova, M.; Moretti, A. et al.
Object Type: Article
System: The UNT Digital Library
Effect of Field Errors in Muon Collider IR Magnets on Beam Dynamics (open access)

Effect of Field Errors in Muon Collider IR Magnets on Beam Dynamics

In order to achieve peak luminosity of a Muon Collider (MC) in the 10{sup 35} cm{sup -2}s{sup -1} range very small values of beta-function at the interaction point (IP) are necessary ({beta}* {le} 1 cm) while the distance from IP to the first quadrupole can not be made shorter than {approx}6 m as dictated by the necessity of detector protection from backgrounds. In the result the beta-function at the final focus quadrupoles can reach 100 km making beam dynamics very sensitive to all kind of errors. In the present report we consider the effects on momentum acceptance and dynamic aperture of multipole field errors in the body of IR dipoles as well as of fringe-fields in both dipoles and quadrupoles in the ase of 1.5 TeV (c.o.m.) MC. Analysis shows these effects to be strong but correctable with dedicated multipole correctors.
Date: May 1, 2012
Creator: Alexahin, Y.; Gianfelice-Wendt, E.; Kapin, V.V. & /Fermilab
Object Type: Article
System: The UNT Digital Library
Biomass Resource Allocation Among Competing End Uses (open access)

Biomass Resource Allocation Among Competing End Uses

The Biomass Scenario Model (BSM) is a system dynamics model developed by the U.S. Department of Energy as a tool to better understand the interaction of complex policies and their potential effects on the biofuels industry in the United States. However, it does not currently have the capability to account for allocation of biomass resources among the various end uses, which limits its utilization in analysis of policies that target biomass uses outside the biofuels industry. This report provides a more holistic understanding of the dynamics surrounding the allocation of biomass among uses that include traditional use, wood pellet exports, bio-based products and bioproducts, biopower, and biofuels by (1) highlighting the methods used in existing models' treatments of competition for biomass resources; (2) identifying coverage and gaps in industry data regarding the competing end uses; and (3) exploring options for developing models of biomass allocation that could be integrated with the BSM to actively exchange and incorporate relevant information.
Date: May 1, 2012
Creator: Newes, Emily; Bush, Brian; Inman, Daniel; Lin, Yolanda; Mai, Trieu; Martinez, Andrew et al.
Object Type: Report
System: The UNT Digital Library
Renewable Energy Atlas of the United States. (open access)

Renewable Energy Atlas of the United States.

The Renewable Energy Atlas (Atlas) of the United States is a compilation of geospatial data focused on renewable energy resources, federal land ownership, and base map reference information. It is designed for the U.S. Department of Agriculture Forest Service (USFS) and other federal land management agencies to evaluate existing and proposed renewable energy projects. Much of the content of the Atlas was compiled at Argonne National Laboratory (Argonne) to support recent and current energy-related Environmental Impact Statements and studies, including the following projects: (1) West-wide Energy Corridor Programmatic Environmental Impact Statement (PEIS) (BLM 2008); (2) Draft PEIS for Solar Energy Development in Six Southwestern States (DOE/BLM 2010); (3) Supplement to the Draft PEIS for Solar Energy Development in Six Southwestern States (DOE/BLM 2011); (4) Upper Great Plains Wind Energy PEIS (WAPA/USFWS 2012, in progress); and (5) Energy Transport Corridors: The Potential Role of Federal Lands in States Identified by the Energy Policy Act of 2005, Section 368(b) (in progress). This report explains how to add the Atlas to your computer and install the associated software; describes each of the components of the Atlas; lists the Geographic Information System (GIS) database content and sources; and provides a brief introduction to the …
Date: May 1, 2012
Creator: Kuiper, J. A.; Hlava, K.; Greenwood, H. & Carr, A.
Object Type: Report
System: The UNT Digital Library
Effects of Electromagnetic Fields on Fish and Invertebrates: Task 2.1.3: Effects on Aquatic Organisms - Fiscal Year 2011 Progress Report - Environmental Effects of Marine and Hydrokinetic Energy (open access)

Effects of Electromagnetic Fields on Fish and Invertebrates: Task 2.1.3: Effects on Aquatic Organisms - Fiscal Year 2011 Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

This fiscal year (FY) 2011 progress report (Task 2.1.3 Effects on Aquatic Organisms, Subtask 2.3.1.1 Electromagnetic Fields) describes studies conducted by PNNL as part of the DOE Wind and Water Power Program to examine the potential effects of electromagnetic fields (EMF) from marine and hydrokinetic devices on aquatic organisms, including freshwater and marine fish and marine invertebrates. In this report, we provide a description of the methods and results of experiments conducted in FY 2010-FY 2011 to evaluate potential responses of selected aquatic organisms. Preliminary EMF laboratory experiments during FY 2010 and 2011 entailed exposures with representative fish and invertebrate species including juvenile coho salmon (Oncorhynchus kisutch), Atlantic halibut (Hippoglossus hippoglossus), California halibut (Paralicthys californicus), rainbow trout (Oncorhynchus mykiss), and Dungeness crab (Metacarcinus magister). These species were selected for their ecological, commercial, and/or recreational importance, as well as their potential to encounter an MHK device or transmission cable during part or all of their life cycle. Based on previous studies, acute effects such as mortality were not expected to occur from EMF exposures. Therefore, our measurement endpoints focused on behavioral responses (e.g., detection of EMF, interference with feeding behavior, avoidance or attraction to EMF), developmental changes (i.e., growth and survival …
Date: May 1, 2012
Creator: Woodruff, Dana L.; Schultz, Irvin R.; Marshall, Kathryn E.; Ward, Jeffrey A. & Cullinan, Valerie I.
Object Type: Report
System: The UNT Digital Library
Analysis and Design of MEBT Beam Absorber for Project-X (open access)

Analysis and Design of MEBT Beam Absorber for Project-X

A beam absorber is needed for a new high power accelerator to be built in Fermilab. It is called Project-X and should replace the existing linac and the 8 GeV Booster synchrotron. The beam absorber is part of the bunch-by-bunch chopper assigned to create an arbitrary bunch sequence required by experimental program. It will be located in the middle of the medium energy beam transport (MEBT) and has to remove the unnecessary bunches from the initially uniform bunch structure supplied by 2.1 MeV CW RFQ. At nominal RFQ beam current of 5 mA, the maximum power delivered to the beam absorber is about 10 kW. Beam optics requirements result in that the length allocated to the beam absorber is short ({approx}400 mm) and the beam size is small ({sigma}{approx}2mm). That yields high power density of the beam arriving to the absorber. The paper presents the thermal and mechanical analysis of one of proposed designs.
Date: May 1, 2012
Creator: Awida, Mohamed H.; Lebedev, Valeri & Yakovlev, Vyacheslav P.
Object Type: Article
System: The UNT Digital Library
NREL Develops Heat Pump Water Heater Simulation Model (Fact Sheet) (open access)

NREL Develops Heat Pump Water Heater Simulation Model (Fact Sheet)

A new simulation model helps researchers evaluate real-world impacts of heat pump water heaters in U.S. homes.
Date: May 1, 2012
Creator: Hudon, K.
Object Type: Report
System: The UNT Digital Library
IEA Wind Task 26: The Past and Future Cost of Wind Energy, Work Package 2 (open access)

IEA Wind Task 26: The Past and Future Cost of Wind Energy, Work Package 2

Over the past 30 years, wind power has become a mainstream source of electricity generation around the world. However, the future of wind power will depend a great deal on the ability of the industry to continue to achieve cost of energy reductions. In this summary report, developed as part of the International Energy Agency Wind Implementing Agreement Task 26, titled 'The Cost of Wind Energy,' we provide a review of historical costs, evaluate near-term market trends, review the methods used to estimate long-term cost trajectories, and summarize the range of costs projected for onshore wind energy across an array of forward-looking studies and scenarios. We also highlight the influence of high-level market variables on both past and future wind energy costs.
Date: May 1, 2012
Creator: Lantz, E.; Wiser, R. & Hand, M.
Object Type: Report
System: The UNT Digital Library
A High-power 650 MHz CW Magnetron Transmitter for Intensity Frontier Superconducting Accelerators (open access)

A High-power 650 MHz CW Magnetron Transmitter for Intensity Frontier Superconducting Accelerators

None
Date: May 1, 2012
Creator: Treado, T. A.; Chase, B.; Nagaitsev, S.; Pasquinelli, R. J.; Yakovlev, V. P.; Flanagan, G. et al.
Object Type: Article
System: The UNT Digital Library
Explicitly Accounting for Protected Lands within the GCAM 3.0 (open access)

Explicitly Accounting for Protected Lands within the GCAM 3.0

The Global Change Assessment Model Version 3.0 defines three different levels of “Protected Lands” within the agricultural and landuse component. These three different scenarios effectively cordon off 3.5% (5.0 million km2) of the Earth’s terrestrial lands in the de minimus Protected Land Scenario, 5.0% (7.20 million km2) in the Core Protected Land Scenario, and 8.2% (11.8 million km2) in the Expanded Protected Land Scenario. None of these scenarios represents the “right” level of Protected Lands for the planet today or tomorrow. Rather, the goal is to create a range of scenarios that can be used in modeling human responses to climate change and the impact those would have on managed and unmanaged terrestrial lands. These scenarios harness the wealth of information in the United Nations Environment Programme World Conservation Monitoring Centre’s World Database on Protected Areas and its categories of explicit degrees of protection.
Date: May 1, 2012
Creator: Dooley, James J. & Zhou, Yuyu
Object Type: Report
System: The UNT Digital Library
Evaluating operating system vulnerability to memory errors. (open access)

Evaluating operating system vulnerability to memory errors.

Reliability is of great concern to the scalability of extreme-scale systems. Of particular concern are soft errors in main memory, which are a leading cause of failures on current systems and are predicted to be the leading cause on future systems. While great effort has gone into designing algorithms and applications that can continue to make progress in the presence of these errors without restarting, the most critical software running on a node, the operating system (OS), is currently left relatively unprotected. OS resiliency is of particular importance because, though this software typically represents a small footprint of a compute node's physical memory, recent studies show more memory errors in this region of memory than the remainder of the system. In this paper, we investigate the soft error vulnerability of two operating systems used in current and future high-performance computing systems: Kitten, the lightweight kernel developed at Sandia National Laboratories, and CLE, a high-performance Linux-based operating system developed by Cray. For each of these platforms, we outline major structures and subsystems that are vulnerable to soft errors and describe methods that could be used to reconstruct damaged state. Our results show the Kitten lightweight operating system may be an easier …
Date: May 1, 2012
Creator: Ferreira, Kurt Brian; Bridges, Patrick G. (University of New Mexico); Pedretti, Kevin Thomas Tauke; Mueller, Frank (North Carolina State University); Fiala, David (North Carolina State University) & Brightwell, Ronald Brian
Object Type: Report
System: The UNT Digital Library
6 Batch Injection and Slipped Beam Tune Measurements in Fermilab?s Main Injector (open access)

6 Batch Injection and Slipped Beam Tune Measurements in Fermilab?s Main Injector

During NOVA operations it is planned to run the Fermilab Recycler in a 12 batch slip stacking mode. In preparation for this, measurements of the tune during a six batch injection and then as the beam is decelerated by changing the RF frequency have been carried out in the Main Injector. The coherent tune shifts due to the changing beam intensity were measured and compared well with the theoretically expected tune shift. The tune shifts due to changing RF frequency, required for slip stacking, also compare well with the linear theory, although some nonlinear affects are apparent at large frequency changes. These results give us confidence that the expected tunes shifts during 12 batch slip stacking Recycler operations can be accommodated.
Date: May 1, 2012
Creator: Scott, D. J.; Capista, D.; Kourbanis, I.; Seiya, K. & Yan, M.-J.
Object Type: Article
System: The UNT Digital Library
FY12 annual Report: PHEV Engine Control and Energy Management Strategy (open access)

FY12 annual Report: PHEV Engine Control and Energy Management Strategy

The objectives are: (1) Investigate novel engine control strategies targeted at rapid engine/catalyst warming for the purpose of mitigating tailpipe emissions from plug-in hybrid electric vehicles (PHEV) exposed to multiple engine cold start events; (2) Optimize integration of engine control strategies with hybrid supervisory control strategies in order to reduce cold start emissions and fuel consumption of PHEVs; and (3) Ensure that development of new vehicle technologies complies with existing emission standards.
Date: May 1, 2012
Creator: Chambon, Paul H.
Object Type: Report
System: The UNT Digital Library
Pressure Sensitivity Characterization of Superconducting Spoke Cavities (open access)

Pressure Sensitivity Characterization of Superconducting Spoke Cavities

None
Date: May 1, 2012
Creator: Awida, M.H.; Gonin, I.V.; Ristori, L.; Yakovlev, V.P.; /Fermilab; Passarelli, D. et al.
Object Type: Article
System: The UNT Digital Library
Imaging Thomson scattering measurements of radiatively heated Xe (open access)

Imaging Thomson scattering measurements of radiatively heated Xe

Uniform density and temperature Xe plasmas have been produced over >4 mm scale-lengths using x-rays generated in a cylindrical Pb cavity. The cavity is 750 {micro}m in depth and diameter, and is heated by a 300 J, 2 ns square, 1054 nm laser pulse focused to a spot size of 200 {micro}m at the cavity entrance. The plasma is characterized by simultaneous imaging Thomson scattering measurements from both the electron and ion scattering features. The electron feature measurement determines the spatial electron density and temperature profile, and using these parameters as constraints in the ion feature analysis allows an accurate determination of the charge state of the Xe ions. The Thomson scattering probe beam is 40 J, 200 ps, and 527 nm, and is focused to a 100 {micro}m spot size at the entrance of the Pb cavity. Each system has a spatial resolution of 25 {micro}m, a temporal resolution of 200 ps (as determined by the probe duration), and a spectral resolution of 2 nm for the electron feature system and 0.025 nm for the ion feature system. The experiment is performed in a Xe filled target chamber at a neutral pressure of 3-10 Torr, and the x-rays produced …
Date: May 1, 2012
Creator: Pollock, B.; Meinecke, J.; Kuschel, S.; Ross, J. S.; Divol, L.; Glenzer, S. H. et al.
Object Type: Article
System: The UNT Digital Library
Technology Assessment: NREL Provides Know-How for Highly Energy-Efficient Data Centers (Fact Sheet) (open access)

Technology Assessment: NREL Provides Know-How for Highly Energy-Efficient Data Centers (Fact Sheet)

NREL leads the effort to change how energy is used worldwide by helping identify and eliminate barriers to energy efficiency and clean energy technology deployment. The laboratory takes a portfolio approach that explores the full range of technology options for developing and implementing innovative energy performance solutions. The Research Support Facility (RSF) data center is a prime example of NREL's capabilities and expertise in energy efficiency. But, more important, its features can be replicated. NREL provides custom technical assistance and training for improved data center performance to help our customers realize cost savings.
Date: May 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Energy Resource Center: Chart a Path to Continuous Energy Improvement (Postcard) (open access)

Energy Resource Center: Chart a Path to Continuous Energy Improvement (Postcard)

Postcard handout created for the Advanced Manufacturing Office to be used at meetings, presentations, and exhibits.
Date: May 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library