Beam commissioning results for the RFQ and MEBT of the EBIS based preinjector for RHIC (open access)

Beam commissioning results for the RFQ and MEBT of the EBIS based preinjector for RHIC

The EBIS based preinjector for both the Relativistic Heavy Ion Collider (RHIC) and NASA Space Radiation Laboratory (NSRL) is now being commissioned at Brookhaven National Laboratory (BNL). In 2008, the RFQ for the project was delivered and commissioned using Test EBIS, which was built to demonstrate the high current EBIS's performance. A dedicated beamline after the RFQ was assembled to confirm the RFQ's performance, and the beam energy was measured by a bending dipole magnet. In November 2009, the RFQ was moved to the final location and the vanes were realigned. The beam commissioning with the RHIC-EBIS was started again during March 2010. The RFQ accelerates ions from 17 keV/u to 300 keV/u and operates at 100.625 MHz. It is followed by a short Medium Energy Beam Transport (MEBT), which consists of four quadrupoles and one buncher cavity. Some temporary diagnostics for this commissioning include an emittance probe, TOF system, fast Faraday cup, and beam current measurement units. As of September 2010, the RFQ and the MEBT show expected performance with He{sup +}, Au{sup 32+} and Fe{sup 20+} beams. Further commissioning for higher intensity beams is in progress.
Date: September 12, 2010
Creator: Okamura, M.; Alessi, J.; Beebe, E.; Kondo, K.; Lambiase, R.; Lockey, R. et al.
Object Type: Article
System: The UNT Digital Library
Commissioning of the EBIS-based heavy ion preinjector at Brookhaven (open access)

Commissioning of the EBIS-based heavy ion preinjector at Brookhaven

The status is presented of the commissioning of a new heavy ion preinjector at Brookhaven National Laboratory. This preinjector uses an Electron Beam Ion Source (EBIS), and an RFQ and IH Linac, both operating at 100.625 MHz, to produce 2 MeV/u ions of any species for use, after further acceleration, at the Relativistic Heavy Ion Collider (RHIC) and the NASA Space Radiation Laboratory (NSRL). Among the increased capabilities provided by this preinjector are the ability to produce ions of any species, and the ability to switch between multiple species in 1 second, to simultaneously meet the needs of both science programs. For initial setup, helium beam from EBIS was injected and circulated in the Booster synchrotron. Following this, accelerated Au{sup 32+} and Fe{sup 20+} beams were transported to the Booster injection point, fulfilling DOE requirements for project completion.
Date: September 12, 2010
Creator: Alessi, J.; Beebe, E.; Binello, S.; Hoff, L.; Kondo, K.; Lambiase, R. et al.
Object Type: Article
System: The UNT Digital Library
Development of stripper options for FRIB (open access)

Development of stripper options for FRIB

The US Department of Energy Facility for Rare Isotope Beams (FRIB) at Michigan State University includes a heavy ion superconducting linac capable of accelerating all ions up to uranium with energies higher than 200 MeV/u and beam power up to 400 kW. To achieve these goals with present ion source performance it is necessary to accelerate simultaneously two charge states of uranium from the ion source in the first section of the linac. At an energy of approximately 16.5 MeV/u it is planned to strip the uranium beam to reduce the voltage needed in the rest of the linac to achieve the final energy. Up to five different charge states are planned to be accelerated simultaneously after the stripper. The design of the stripper is a challenging problem due to the high power deposited (approximately 0.7 kW) in the stripper media by the beam in a small spot. To assure success of the project we have established a research and development program that includes several options: carbon or diamond foils, liquid lithium films, gas strippers and plasma strippers. We present in this paper the status of the different options.
Date: September 12, 2010
Creator: Marti, F.; Hershcovitch, A.; Momozaki, Y.; Nolen, J.; Reed, C. & Thieberger, P.
Object Type: Article
System: The UNT Digital Library
A new medium energy beam transport line for the proton injector of AGS-RHIC (open access)

A new medium energy beam transport line for the proton injector of AGS-RHIC

In Brookhaven National Laboratory (BNL), a 750 keV medium energy beam transport line between the 201 MHz 750 keV proton RFQ and the 200 MeV Alvarez DTL is being modified to get a better transmission of the beam. Within a tight space, high field gradient quadrupoles (65 Tm) and newly designed steering magnets (6.5 mm in length) will be installed considering the cross-talk effects. Also a new half wave length 200 MHz buncher is being prepared. The beam commissioning will be done in this year. To enhance the performance of the proton linacs, the MEBT is being modified. New quadrupole magnets, steering magnets and a half wave length buncher as shown in Figure 7 will be installed and be commissioned soon.
Date: September 12, 2010
Creator: Okamura, M.; Briscoe, B.; Fite, J.; LoDestro, V.; Raparia, D.; Ritter, J. et al.
Object Type: Article
System: The UNT Digital Library
NLM Web Resources for Environmental Health and Biomedical Research (open access)

NLM Web Resources for Environmental Health and Biomedical Research

The National Library of Medicine (NLM) is sponsoring this course to increase awareness of the availability and value of NLM’s online environmental health and toxicology information resources that provide invaluable tools to address these issues—for professionals and consumers alike. Participants will receive hands-on practice with selected NLM resources, and demonstrations of other valuable resources will be provided.
Date: September 12, 2010
Creator: Foster, R.
Object Type: Book
System: The UNT Digital Library
Accelerated Gibbs Sampling for Infinite Sparse Factor Analysis (open access)

Accelerated Gibbs Sampling for Infinite Sparse Factor Analysis

The Indian Buffet Process (IBP) gives a probabilistic model of sparse binary matrices with an unbounded number of columns. This construct can be used, for example, to model a fixed numer of observed data points (rows) associated with an unknown number of latent features (columns). Markov Chain Monte Carlo (MCMC) methods are often used for IBP inference, and in this technical note, we provide a detailed review of the derivations of collapsed and accelerated Gibbs samplers for the linear-Gaussian infinite latent feature model. We also discuss and explain update equations for hyperparameter resampling in a 'full Bayesian' treatment and present a novel slice sampler capable of extending the accelerated Gibbs sampler to the case of infinite sparse factor analysis by allowing the use of real-valued latent features.
Date: September 12, 2011
Creator: Andrzejewski, D M
Object Type: Report
System: The UNT Digital Library
Annual Illness and Injury Surveillance Report: Savannah River Site, 2010 (open access)

Annual Illness and Injury Surveillance Report: Savannah River Site, 2010

The U.S. Department of Energy's (DOE) commitment to assuring the health and safety of its workers includes the conduct of illness and injury surveillance activities that provide an early warning system to detect health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: September 12, 2011
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
ARM Cloud Retrieval Ensemble Data Set (ACRED) (open access)

ARM Cloud Retrieval Ensemble Data Set (ACRED)

This document describes a new Atmospheric Radiation Measurement (ARM) data set, the ARM Cloud Retrieval Ensemble Data Set (ACRED), which is created by assembling nine existing ground-based cloud retrievals of ARM measurements from different cloud retrieval algorithms. The current version of ACRED includes an hourly average of nine ground-based retrievals with vertical resolution of 45 m for 512 layers. The techniques used for the nine cloud retrievals are briefly described in this document. This document also outlines the ACRED data availability, variables, and the nine retrieval products. Technical details about the generation of ACRED, such as the methods used for time average and vertical re-grid, are also provided.
Date: September 12, 2011
Creator: Zhao, C.; Xie, S.; Klein, S. A.; McCoy, R.; Comstock, J. M.; Delanoë, J. et al.
Object Type: Report
System: The UNT Digital Library
Beam Position Monitor System for PEP II (open access)

Beam Position Monitor System for PEP II

We describe the beam position monitor system built for PEP-II, the B-factory at SLAC. The system reports beam position for bunches of between 5 x 10{sup 8} and 8 x 10{sup 10} electron charges, either singly or as continuous streams of bunches every 4.2 ns. Resolution at full charge is to be better than 10 microns in a single turn. Higher resolution is available via on-board multi-turn averaging. The position signal is processed in a 20 MHz bandwidth around 952 MHz. This bandwidth, rather broader than that typical of RF position monitors, allows good resolution for low charge single bunches. Additional novel features include stringent control of return losses in order to minimize cross-talk between nearby bunches which may contain very different charges. The digitizing electronics is multiplexed between the two PEP-II storage rings. Design, construction, and installation experience, as well as first results with beam are presented.
Date: September 12, 2011
Creator: Smith, Stephen R.; Aiello, G.Roberto; Hendrickson, Linda J.; Johnson, Ronald G.; Mills, Mark R. & Olsen, Jeff J.
Object Type: Article
System: The UNT Digital Library
BNL Direct Wind Superconducting Magnets (open access)

BNL Direct Wind Superconducting Magnets

BNL developed Direct Wind magnet technology is used to create a variety of complex multi-functional multi-layer superconducting coil structures without the need for creating custom production tooling and fixturing for each new project. Our Direct Wind process naturally integrates prestress into the coil structure so external coil collars and yokes are not needed; the final coil package transverse size can then be very compact. Direct Wind magnets are produced with very good field quality via corrections applied during the course of coil winding. The HERA-II and BEPC-II Interaction Region (IR) magnet, J-PARC corrector and Alpha antihydrogen magnetic trap magnets and our BTeV corrector magnet design are discussed here along with a full length ILC IR prototype magnet presently in production and the coils that were wound for an ATF2 upgrade at KEK. A new IR septum magnet design concept for a 6.2 T combined-function IR magnet for eRHIC, a future RHIC upgrade, is introduced here.
Date: September 12, 2011
Creator: Parker, B.; Anerella, M.; Escallier, J.; Ghosh, A.; Jain, A.; Marone, A. et al.
Object Type: Article
System: The UNT Digital Library
A Compact X-Band Linac for an X-Ray FEL (open access)

A Compact X-Band Linac for an X-Ray FEL

With the growing demand for FEL light sources, cost issues are being reevaluated. To make the machines more compact, higher frequency room temperature linacs are being considered, specifically ones using C-band (5.7 GHz) rf technology, for which 40 MV/m gradients are achievable. In this paper, we show that an X-band (11.4 GHz) linac using the technology developed for NLC/GLC can provide an even lower cost solution. In particular, stable operation is possible at gradients of 100 MV/m for single bunch operation and 70 MV/m for multibunch operation. The concern, of course, is whether the stronger wakefields will lead to unacceptable emittance dilution. However, we show that the small emittances produced in a 250 MeV, low bunch charge, LCLS-like S-band injector and bunch compressor can be preserved in a multi-GeV X-band linac with reasonable alignment tolerances. The successful lasing and operation of the LCLS [1] has generated world-wide interest in X-ray FELs. The demand for access to such a light source by researchers eager to harness the capabilities of this new tool far exceeds the numbers that can be accommodated, spurring plans for additional facilities. Along with cost, spatial considerations become increasingly important for a hard X-ray machine driven by a …
Date: September 12, 2011
Creator: Adolphsen, Chris; Huang, Zhirong; Bane, Karl L. F.; Li, Zenghai; Zhou, Feng; Wang, Faya et al.
Object Type: Article
System: The UNT Digital Library
Demonstration of a 17 cm robust carbon fiber deformable mirror for adaptive optics (open access)

Demonstration of a 17 cm robust carbon fiber deformable mirror for adaptive optics

Carbon-fiber reinforced polymer (CFRP) composite is an attractive material for fabrication of optics due to its high stiffness-to-weight ratio, robustness, zero coefficient of thermal expansion (CTE), and the ability to replicate multiple optics from the same mandrel. We use 8 and 17 cm prototype CFRP thin-shell deformable mirrors to show that residual CTE variation may be addressed with mounted actuators for a variety of mirror sizes. We present measurements of surface quality at a range of temperatures characteristic of mountaintop observatories. For the 8 cm piece, the figure error of the Al-coated reflective surface under best actuator correction is {approx}43 nm RMS. The 8 cm mirror has a low surface error internal to the outer ring of actuators (17 nm RMS at 20 C and 33 nm RMS at -5 C). Surface roughness is low (< 3 nm P-V) at a variety of temperatures. We present new figure quality measurements of the larger 17 cm mirror, showing that the intra-actuator figure error internal to the outer ring of actuators (38 nm RMS surface with one-third the actuator density of the 8 cm mirror) does not scale sharply with mirror diameter.
Date: September 12, 2011
Creator: Ammons, S. M.; Hart, M.; Coughenour, B.; Romeo, R.; Martin, R. & Rademacher, M.
Object Type: Article
System: The UNT Digital Library
designer phase transitions in lithium-based spinels (open access)

designer phase transitions in lithium-based spinels

When electrons in a metal become correlated with each other, new cooperative behavior can arise. This correlation is magnified when the metal has magnetic ions embedded in it. These atomic magnets try to line up with each other, but in doing so actually create a correlation between the motions of conduction electrons. In turn, these correlated electron motions prevent the magnetic ions from aligning, even at zero Kelvin. When this competition is strongest (at the so-called quantum critical point-QCP) the response of the system can no longer be described using the text book theory for metals. In addition, a range of new phenomena has been seen to emerge in the vicinity of a QCP, such as heavy-fermion superconductivity, coexistence of magnetism and superconductivity and hyper-scaling. The main goal of our research is to try to unravel the details of the feedback mechanism between electron motion and magnetism that lies at the heart of this new physics. We have chosen lithium-based spinel structures as the most promising family of systems to achieve our goal. Known lithium-based spinels Li{sub x}M{sub 2}O{sub 4} [M=V, Ti and Mn] show a variety of ground states: heavy-fermion, superconducting, or geometrically frustrated local moment systems. Li{sub x}M{sub …
Date: September 12, 2011
Creator: Montfrooij, Wouter
Object Type: Report
System: The UNT Digital Library
Discovery of the Omega Minus: 1964 - Parity, Neutrinos, Heavy Ions, RBRC: T.D. Lee and Me (open access)

Discovery of the Omega Minus: 1964 - Parity, Neutrinos, Heavy Ions, RBRC: T.D. Lee and Me

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Date: September 12, 2011
Creator: Samios, N. P.
Object Type: Article
System: The UNT Digital Library
Enhanced Densification of SDC Barrier Layers (open access)

Enhanced Densification of SDC Barrier Layers

This technical report explores the Enhanced Densification of SCD Barrier Layers A samaria-doped ceria (SDC) barrier layer separates the lanthanum strontium cobalt ferrite (LSCF) cathode from the yttria-stabilized zirconia (YSZ) electrolyte in a solid oxide fuel cell (SOFC) to prevent the formation of electrically resistive interfacial SrZrO{sub 3} layers that arise from the reaction of Sr from the LSCF with Zr from the YSZ. However, the sintering temperature of this SDC layer must be limited to {approx}1200 C to avoid extensive interdiffusion between SDC and YSZ to form a resistive CeO{sub 2}-ZrO{sub 2} solid solution. Therefore, the conventional SDC layer is often porous and therefore not as impervious to Sr-diffusion as would be desired. In the pursuit of improved SOFC performance, efforts have been directed toward increasing the density of the SDC barrier layer without increasing the sintering temperature. The density of the SDC barrier layer can be greatly increased through small amounts of Cu-doping of the SDC powder together with increased solids loading and use of an appropriate binder system in the screen print ink. However, the resulting performance of cells with these barrier layers did not exhibit the expected increase in accordance with that achieved with the prototypical …
Date: September 12, 2011
Creator: Hardy, John S.; Templeton, Jared W.; Lu, Zigui & Stevenson, Jeffry W.
Object Type: Report
System: The UNT Digital Library
The Fair Labor Standards Act, Overtime Compensation, and Personal Data Assistants (open access)

The Fair Labor Standards Act, Overtime Compensation, and Personal Data Assistants

This report reviews the FLSA's overtime provisions, and examines some of the U.S. Supreme Court's seminal decisions on work.
Date: September 12, 2011
Creator: Shimabukuro, Jon O.
Object Type: Report
System: The UNT Digital Library
Final Report - Summer Visit 2010 (open access)

Final Report - Summer Visit 2010

During my visit to LLNL during the summer of 2010, I worked on algebraic multilevel solvers for large sparse systems of linear equations arising from discretizations of partial differential equations. The particular solver of interest is based on ILU decomposition. The setup phase for this AMG solve is just the single ILU decomposition, and its corresponding error matrix. Because the ILU uses a minimum degree or similar sparse matrix ordering, most of the fill-in, and hence most of the error, is concentrated in the lower right corner of the factored matrix. All of the major multigrid components - the smoother, the coarse level correction matrices, and the fine-to-coarse and coarse-to-fine rectangular transfer matrices, are defined in terms of various blocks of the ILU factorization. Although such a strategy is not likely to be optimal in terms of convergence properties, it has a relatively low setup cost, and therefore is useful in situations where setup costs for more traditional AMG approaches cannot be amortized over the solution of many linear systems using the same matrix. Such a situation arises in adaptive methods, where often just one linear system is solved at each step of an adaptive feedback loop, or in solving …
Date: September 12, 2011
Creator: Bank, R
Object Type: Report
System: The UNT Digital Library
Five-Year NRHP Re-Evaluation of Historic Buildings Assessment (open access)

Five-Year NRHP Re-Evaluation of Historic Buildings Assessment

The Lawrence Livermore National Laboratory (LLNL) 'Draft Programmatic Agreement among the Department of Energy and the California State Historic Preservation Officer Regarding Operation of Lawrence Livermore National Laboratory' requires a review and re-evaluation of the eligibility of laboratory properties for the National Register of Historic Places (NRHP) every five years. The original evaluation was published in 2005; this report serves as the first five-year re-evaluation. This re-evaluation includes consideration of changes within LLNL to management, to mission, and to the built environment. it also determines the status of those buildings, objects, and districts that were recommended as NRHP-eligible in the 2005 report. Buildings that were omitted from the earlier building list, those that have reached 50 years of age since the original assessment, and new buildings are also addressed in the re-evaluation.
Date: September 12, 2011
Creator: Ullrich, R A & Heidecker, K R
Object Type: Report
System: The UNT Digital Library
FY11 Level-2 Milestone 3953: TLCC2 contract awarded (open access)

FY11 Level-2 Milestone 3953: TLCC2 contract awarded

This report documents completion of FY11 L2 milestone No.3953-TLCC2 contract award. This milestone was scheduled for completion on 3/31/11 and was completed on 4/14/11. There is a separate milestone (3856), due at the end of the fiscal year, concerned with installation of the first LLNL SU and early user access. Efforts related to this tri-lab L2 milestone started early in 2010 with the development of tri-lab requirements for the second ASC capacity system procurement. The SOW was then developed along with necessary RFP paperwork and sent to HQ/DOE for their review prior to being released. There was significant delay in getting this step completed which led to this milestone being put at risk for several months. However, once the RFP was approved and released we were able to get the procurement back on track with aggressive proposal response and review timelines.
Date: September 12, 2011
Creator: Carnes, B
Object Type: Report
System: The UNT Digital Library
In Vivo Monitoring Program Manual, PNL-MA-574, Rev 5.1 (open access)

In Vivo Monitoring Program Manual, PNL-MA-574, Rev 5.1

The following sections provide an overview of the administration for the In Vivo Monitoring Program (IVMP) for Hanford. This includes the organizational structure and program responsibilities; coordination of in vivo measurements; scheduling measurements; performing measurements; reporting results; and quality assurance.
Date: September 12, 2011
Creator: Lynch, Timothy P.
Object Type: Report
System: The UNT Digital Library
Iran Sanctions (open access)

Iran Sanctions

This report focuses on the United States' relationship with Iran and how the Obama Administration is handling prior administrations' economic sanctions against Iran. The Obama Administration's policy approach toward Iran has contrasted with the Bush Administration's by attempting to couple the imposition of sanctions to an active and direct U.S. effort to negotiate with Iran on the nuclear issue. That approach was not initially altered because of the Iranian dispute over its June 12, 2009, elections. However, with subsequent negotiations yielding no firm Iranian agreement to compromise, since early 2010 the Administration has focused on achieving the imposition of additional U.N., U.S., and allied country sanctions whose cumulative effect would be to compel it to accept a nuclear bargain.
Date: September 12, 2011
Creator: Katzman, Kenneth
Object Type: Report
System: The UNT Digital Library
Justice and Law Enforcement: Observations on the Costs and Benefits of an Increased Department of Defense Role in Helping to Secure the Southwest Land Border (open access)

Justice and Law Enforcement: Observations on the Costs and Benefits of an Increased Department of Defense Role in Helping to Secure the Southwest Land Border

Correspondence issued by the Government Accountability Office with an abstract that begins "In order to satisfy the requirement in the Ike Skelton National Defense Authorization Act for Fiscal Year 2011 to report on the security of the southwest land border of the United States, we briefed Congress on July 12, 2011, with our preliminary observations. This is our final report to Congress on the Department of Defense (DOD) issues we addressed in response to the mandate. As directed by the mandate, we assessed: (1) what is known about the costs and benefits of an increased DOD role to help achieve operational control over the southwest land border, including the deployment of additional units, the National Guard, or other DOD personnel; increased use of ground-based mobile surveillance systems by military personnel; and use of additional mobile patrols by military personnel, particularly in rural, high-trafficked areas; and (2) what is known about the costs and benefits of an increased deployment of additional unmanned aerial systems and manned aircraft to provide surveillance; as well as the impact of any increased deployment of unmanned aerial systems or manned aircraft on national airspace use and availability.."
Date: September 12, 2011
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
A Laser Interferometric Miniature Sensor (open access)

A Laser Interferometric Miniature Sensor

This is the second year of a Phase II Small Business Innovation Research (SBIR) contract geared towards the development of a new seismic sensor. Ground-based seismic monitoring systems have proven to be very capable in identifying nuclear tests, and can provide somewhat precise information on the location and yield of the explosive device. Making these measurements, however, currently requires very expensive and bulky seismometers that are difficult to deploy in places where they are most needed. A high performance, compact device can enable rapid deployment of large scale arrays, which can in turn be used to provide higher quality data during times of critical need. The use of a laser interferometer-based device has shown considerable promise, while also presenting significant challenges. The greatest strength of this optical readout technique is the ability to decouple the mechanical design from the transducer, thus enabling a miniaturized design that is not accessible with conventional sensing techniques. However, the nonlinearity in the optical response must be accounted for in the sensor output. Previously, we had proposed using a force-feedback approach to position the sensor at a point of maximum linearity. However, it can be shown that the combined nonlinearities of the optical response and …
Date: September 12, 2011
Creator: Carr, Dustin W.; Baldwin, Patrick C.; Milburn, Howard & Robinson, David
Object Type: Report
System: The UNT Digital Library
Linking Network Microstructure to Macroscopic Properties of Siloxane Elastomers Using Combined Nuclear Magnetic Resonance and Mesoscale Computational Modeling (open access)

Linking Network Microstructure to Macroscopic Properties of Siloxane Elastomers Using Combined Nuclear Magnetic Resonance and Mesoscale Computational Modeling

None
Date: September 12, 2011
Creator: Mayer, B P; Lewicki, J P; Weisgraber, T H; Small, W; Chinn, S C & Maxwell, R S
Object Type: Article
System: The UNT Digital Library