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Alternative Muon Front-end for the International Design Study (IDS) (open access)

Alternative Muon Front-end for the International Design Study (IDS)

We discuss alternative designs of the muon capture front end of the Neutrino Factory International Design Study (IDS). In the front end, a proton bunch on a target creates secondary pions that drift into a capture channel, decaying into muons. A sequence of RF cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. This design is affected by limitations on accelerating gradients within magnetic fields. The effects of gradient limitations are explored, and mitigation strategies are presented.
Date: May 1, 2010
Creator: Alekou, A.; Neuffer, D.; Martini, M.; Prior, G.; Rogers, C.; Stratakis, D. et al.
Object Type: Article
System: The UNT Digital Library
Run-09 pC polarimeter analysis (open access)

Run-09 pC polarimeter analysis

Analysis of PC polarimeter data at {radical}s = 200 and 500 GeV from Run9 is presented. Final polarization results, fill-by-fill, for blue and yellow beams, as to be used by RHIC experiments (in collisions) are released and collected in http://www4.rcf.bnl.gov/cnipol/pubdocs/Run09Offline/. Global relative systematic uncertainties {delta}P/P (to be considered as correlated from fill to fill) are 4.7% for 100 GeV beams, and 8.3% (12.1%) for blue (yellow) 250 GeV beams. For a product of two beam polarizations P{sub B} {center_dot} P{sub Y} (used in double spin asymmetry measurements) the relative uncertainty {delta}(P{sub B} {center_dot} P{sub Y})/(P{sub B} {center_dot} P{sub Y}) 8.8% for 100 GeV beams and 18.5% for 250 GeV beams. For the average between two beam polarization (P{sub B} + P{sub Y})/2 (used in single spin asymmetry measurements, when data from two polarized beams are combined) the relative uncertainty is 4.4% for 100 GeV beams and 9.2% for 250 GeV beams. Larger uncertainties for 250 GeV beams relate to significant rate related systematic effects experienced in the first part of Run9 (due to thicker targets used and smaller trans. beam size at higher beam energy).
Date: August 1, 2010
Creator: Alekseev, I.; Aschenauer, E.; Atoyan, G.; Bazilevsky, A.; Gill, R.; Huang, H. et al.
Object Type: Report
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
Methods Data Qualification Interim Report (open access)

Methods Data Qualification Interim Report

The overall goal of the Next Generation Nuclear Plant (NGNP) Data Management and Analysis System (NDMAS) is to maintain data provenance for all NGNP data including the Methods component of NGNP data. Multiple means are available to access data stored in NDMAS. A web portal environment allows users to access data, view the results of qualification tests and view graphs and charts of various attributes of the data. NDMAS also has methods for the management of the data output from VHTR simulation models and data generated from experiments designed to verify and validate the simulation codes. These simulation models represent the outcome of mathematical representation of VHTR components and systems. The methods data management approaches described herein will handle data that arise from experiment, simulation, and external sources for the main purpose of facilitating parameter estimation and model verification and validation (V&V). A model integration environment entitled ModelCenter is used to automate the storing of data from simulation model runs to the NDMAS repository. This approach does not adversely change the why computational scientists conduct their work. The method is to be used mainly to store the results of model runs that need to be preserved for auditing purposes or …
Date: September 1, 2010
Creator: Alessi, R. Sam; Grimmett, Tami; Vang, Leng & McGrath, Dave
Object Type: Report
System: The UNT Digital Library
Muon Collider design status (open access)

Muon Collider design status

Muon Collider (MC) - proposed by G.I. Budker and A.N. Skrinsky a few decades ago - is now considered as the most exciting option for the energy frontier machine in the post-LHC era. A national Muon Accelerator Program (MAP) is being formed in the USA with the ultimate goal of building a MC at the Fermilab site with c.o.m. energy in the range 1.5-3 TeV and luminosity of {approx} 1.5 {center_dot} 10{sup 34} cm{sup -2} s{sup -1}. As the first step on the way to MC it envisages construction of a Neutrino Factory (NF) for high-precision neutrino experiments. The baseline scheme of the NF-MC complex is presented and possible options for its main components are discussed.
Date: September 1, 2010
Creator: Alexahin, Y.
Object Type: Article
System: The UNT Digital Library
Rapid-cycling synchrotron with variable momentum compaction (open access)

Rapid-cycling synchrotron with variable momentum compaction

There are conflicting requirements on the value of the momentum compaction factor during energy ramping in a synchrotron: at low energies it should be positive and sufficiently large to make the slippage factor small so that it is possible to work closer to the RF voltage crest and ensure sufficient RF bucket area, whereas at higher energies it should be small or negative to avoid transition crossing. In the present report we propose a lattice with a variable momentum compaction factor and consider the possibility of using it in a high repetition rate proton driver for a muon collider and neutrino factory.
Date: May 1, 2010
Creator: Alexahin, Y. & Summers, D. J.
Object Type: Article
System: The UNT Digital Library
Muon collider interaction region design (open access)

Muon collider interaction region design

Design of a muon collider interaction region (IR) presents a number of challenges arising from low {beta}* < 1 cm, correspondingly large beta-function values and beam sizes at IR magnets, as well as the necessity to protect superconducting magnets and collider detectors from muon decay products. As a consequence, the designs of the IR optics, magnets and machine-detector interface are strongly interlaced and iterative. A consistent solution for the 1.5 TeV c.o.m. muon collider IR is presented. It can provide an average luminosity of 10{sup 34} cm{sup -2}s{sup -1} with an adequate protection of magnet and detector components.
Date: May 1, 2010
Creator: Alexahin, Y. I.; Gianfelice-Wendt, E.; Kashikhin, V. V.; Mokhov, N. V.; Zlobin, A. V. & Alexakhin, V. Y.
Object Type: Article
System: The UNT Digital Library
Tune Evaluation From Phased BPM Turn-By-Turn Data (open access)

Tune Evaluation From Phased BPM Turn-By-Turn Data

In fast ramping synchrotrons like the Fermilab Booster the conventional methods of betatron tune evaluation from the turn-by-turn data may not work due to rapid changes of the tunes (sometimes in a course of a few dozens of turns) and a high level of noise. We propose a technique based on phasing of signals from a large number of BPMs which significantly increases the signal to noise ratio. Implementation of the method in the Fermilab Booster control system is described and some measurement results are presented.
Date: May 18, 2010
Creator: Alexahin, Y.; Gianfelice-Wendt, E. & Marsh, W.
Object Type: Article
System: The UNT Digital Library
Conceptual design of the muon collider ring lattice (open access)

Conceptual design of the muon collider ring lattice

Muon collider is a promising candidate for the next energy frontier machine. However, in order to obtain peak luminosity in the 10{sup 35}/cm{sup 2}/s range the collider lattice design must satisfy a number of stringent requirements, such as low beta at IP ({beta}* < 1 cm), large momentum acceptance and dynamic aperture and small value of the momentum compaction factor. Here we present a particular solution for the interaction region optics whose distinctive feature is a three-sextupole local chromatic correction scheme. Together with a new flexible momentum compaction arc cell design this scheme allows to satisfy all the above-mentioned requirements and is relatively insensitive to the beam-beam effect.
Date: May 1, 2010
Creator: Alexahin, Y.; Gianfelice-Wendt, E.; Netepenko, A. & /Fermilab
Object Type: Article
System: The UNT Digital Library
Enhancing the US Power Infrastructure (open access)

Enhancing the US Power Infrastructure

The primary motivation for this set of research activities was to develop a foundation in several aspects of power in order to position Cleveland State University to lead a multiuniversity effort to secure funding for enhanced power system projects and to be able to eventually secure a NASA Space Power Systems Center status through the competitive bidding process. This was accomplished by focusing on these major project areas, (1) the design of the next generation nuclear-electric power generation system, (2) the design of a distributed, fault-tolerant, and modular power system, and (3) the development of the dynamics and control of active magnetic bearings for flywheel energy storage without using conventional sensors.
Date: May 31, 2010
Creator: Alexander, Charles
Object Type: Report
System: The UNT Digital Library
Electron Cloud at Low Emittance in CesrTA (open access)

Electron Cloud at Low Emittance in CesrTA

The Cornell Electron Storage Ring (CESR) has been reconfigured as a test accelerator (CesrTA) for a program of electron cloud (EC) research at ultra low emittance. The instrumentation in the ring has been upgraded with local diagnostics for measurement of cloud density and with improved beam diagnostics for the characterization of both the low emittance performance and the beam dynamics of high intensity bunch trains interacting with the cloud. A range of EC mitigation methods have been deployed and tested and their effectiveness is discussed. Measurements of the electron cloud's effect on the beam under a range of conditions are discussed along with the simulations being used to quantitatively understand these results.
Date: May 23, 2010
Creator: Alexander, J. P.; Billing, M. G.; Calvey, J.; Crittenden, J. A.; Dugan, G.; Eggert, N. et al.
Object Type: Article
System: The UNT Digital Library
The 2010 Oil Spill: Criminal Liability Under Wildlife Laws (open access)

The 2010 Oil Spill: Criminal Liability Under Wildlife Laws

This report highlights the possible ways to prosecute those who caused the 2010 oil spill in the Gulf of Mexico. The report suggests that prosecution can be done under laws such as the ESA (Endangered Species Act) or the MMPA (Marine Mammal Protection Act) both of which provide for civil and criminal punishment. However, the most likely law to be used will be the MBTA (Migratory Bird Treatment Act) which makes it a crime to kill migratory birds. The report suggests that the MBTA would be the best method to prosecute for criminal liability.
Date: August 31, 2010
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
The 2010 Oil Spill: Criminal Liability Under Wildlife Laws (open access)

The 2010 Oil Spill: Criminal Liability Under Wildlife Laws

In April 2010 an explosion occurred on an oil rig in the Gulf of Mexico, reportedly killing 11 people, and, according to federal experts, causing the worst oil spill in U.S. history. Millions of barrels of oil are believed to have leaked into the Gulf of Mexico. As the oil spreads, the implications for harm to wildlife grow. The United States has many laws that protect wildlife from harm. This report discusses three: the Endangered Species Act, the Marine Mammal Protection Act, and the Migratory Bird Treaty Act.
Date: June 28, 2010
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
The 2010 Oil Spill: MMS/BOEMRE and NEPA (open access)

The 2010 Oil Spill: MMS/BOEMRE and NEPA

This report reviews the environmental procedures required following the explosion of an oil well on a tract leased by BP from the federal government.
Date: August 19, 2010
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
The 2010 Oil Spill: Natural Resource Damage Assessment Under the Oil Pollution Act (open access)

The 2010 Oil Spill: Natural Resource Damage Assessment Under the Oil Pollution Act

The 2010 Deepwater Horizon oil spill leaked an estimated 4.1 million barrels of oil into the Gulf of Mexico, damaging the waters, shores, and marshes, and the fish and wildlife that live there. When resources in the public trust are harmed by contamination, federal, state, foreign, and tribal governments may seek compensation for damage to natural resources under certain laws. This is done in two steps: first, by assessing the harm; then, by determining how and what restoration will take place. Compensation for natural resource damage is intended to restore the natural resources to their condition before the damage and to compensate the public for the lost use of those resources. This report discusses legislation that provides a framework for assessing and mitigating the damage caused by such spills.
Date: September 8, 2010
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
The 2010 Oil Spill: The Minerals Management Service (MMS) and the National Environmental Policy Act (NEPA) (open access)

The 2010 Oil Spill: The Minerals Management Service (MMS) and the National Environmental Policy Act (NEPA)

This report will review environmental procedures after an exploratory oil well in the Gulf of Mexico exploded, killing 11 people and causing an oil spill.
Date: June 4, 2010
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
Does the Endangered Species Act Listing Provide More Protection of the Polar Bear? (open access)

Does the Endangered Species Act Listing Provide More Protection of the Polar Bear?

None
Date: November 10, 2010
Creator: Alexander, Kristina
Object Type: Report
System: The UNT Digital Library
Gray Wolves Under the Endangered Species Act: Distinct Population Segments and Experimental Populations (open access)

Gray Wolves Under the Endangered Species Act: Distinct Population Segments and Experimental Populations

This report analyzes the DPS designation process as it is applied to the gray wolf. It also examines experimental populations of wolves under the ESA and their protections. As part of its oversight responsibilities, Congress has conducted hearings on the Fish and Wildlife Service’s application of science to endangered species.
Date: August 10, 2010
Creator: Alexander, Kristina & Corn, M. L.
Object Type: Report
System: The UNT Digital Library
Ergonomics in the Biosciences (open access)

Ergonomics in the Biosciences

None
Date: April 12, 2010
Creator: Alexandre, Melanie
Object Type: Report
System: The UNT Digital Library
Ready, set...go! (open access)

Ready, set...go!

The objectives of this paper are: (1) Discuss organizational readiness for changes in an ergonomics program or intervention; (2) Assessing organizational readiness; (3) Benefits and challenges of change; and (4) Case studies of ergonomic programs that were 'not ready' and 'ready'.
Date: June 16, 2010
Creator: Alexandre, Melanie
Object Type: Report
System: The UNT Digital Library
Ergonomics and Engineering - Designing for the perfect fit...even for Cinderella's glass slipper (open access)

Ergonomics and Engineering - Designing for the perfect fit...even for Cinderella's glass slipper

None
Date: February 9, 2010
Creator: Alexandre, Melanie & Naca, Christine
Object Type: Report
System: The UNT Digital Library
Computational Investigation of FeS2 Surfaces and Prediction of Effects of Sulfur Environment on Stabilities (open access)

Computational Investigation of FeS2 Surfaces and Prediction of Effects of Sulfur Environment on Stabilities

Density functional theory calculations were employed to investigate the (001), (210), (III), and (110) surfaces of, F~S2' The surface free ene:gies were calculated in equilibrium with a sulfur environment using firstpnnclples based thermodynamics approach. Surfaces that feature metal atoms in their outermost layer are predicted to be higher m energy. Wlthm the studied subset of (I x I) terminations, the stoichiometric (001) surface termmated by a layer of sulfur atoms is the most stable for sulfur-lean condition. For increasingly sulfur-nch enVIronment, two structures were found to have notably lower surface energies compared to others. They have (210) and (Ill) orientation, both terminated by layers of sulfur. Interestingly, these surfaces are nonstoichiometric exhibiting an excess of sulfur atoms.
Date: January 1, 2010
Creator: Alfonso, D. R.
Object Type: Article
System: The UNT Digital Library
NIF Target Assembly Metrology and Results (open access)

NIF Target Assembly Metrology and Results

None
Date: February 9, 2010
Creator: Alger, E T; Kroll, J J; Hughes, J; Dzenitis, E G; Montesanti, R; Swisher, M et al.
Object Type: Article
System: The UNT Digital Library
Helium measurements of pore-fluids obtained from SAFOD drillcore (open access)

Helium measurements of pore-fluids obtained from SAFOD drillcore

{sup 4}He accumulated in fluids is a well established geochemical tracer used to study crustal fluid dynamics. Direct fluid samples are not always collectable; therefore, a method to extract rare gases from matrix fluids of whole rocks by diffusion has been adapted. Helium was measured on matrix fluids extracted from sandstones and mudstones recovered during the San Andreas Fault Observatory at Depth (SAFOD) drilling in California, USA. Samples were typically collected as subcores or from drillcore fragments. Helium concentration and isotope ratios were measured 4-6 times on each sample, and indicate a bulk {sup 4}He diffusion coefficient of 3.5 {+-} 1.3 x 10{sup -8} cm{sup 2}s{sup -1} at 21 C, compared to previously published diffusion coefficients of 1.2 x 10{sup -18} cm{sup 2}s{sup -1} (21 C) to 3.0 x 10{sup -15} cm{sup 2}s{sup -1} (150 C) in the sands and clays. Correcting the diffusion coefficient of {sup 4}He{sub water} for matrix porosity ({approx}3%) and tortuosity ({approx}6-13) produces effective diffusion coefficients of 1 x 10{sup -8} cm{sup 2}s{sup -1} (21 C) and 1 x 10{sup -7} (120 C), effectively isolating pore fluid {sup 4}He from the {sup 4}He contained in the rock matrix. Model calculations indicate that <6% of helium initially …
Date: April 15, 2010
Creator: Ali, S.; Stute, M.; Torgersen, T.; Winckler, G. & Kennedy, B.M.
Object Type: Article
System: The UNT Digital Library