Proceedings of RIKIN BNL Research Center Workshop - Volume 79 (open access)

Proceedings of RIKIN BNL Research Center Workshop - Volume 79

Since the earliest days of ultra-relativistic heavy ion physics, there has been interest in strange particle production. Originally, an anomalously large strangeness production was believed to be a signature of the Quark Gluon Plasma. Now the flavor composition of the plasma as reflected in the ratios of abundances of strange and non-strange particles is believed by advocates to tell us the temperature and baryon number density of the Quark Gluon Plasma at decoupling. In addition, there are arguments that suggest that the abundances of strange particles might at intermediate energy or at non-central rapidity, signal the existence of a critical end point of phase transitions in the baryon number chemical potential temperature plane. The purpose of this workshop is to assess the current theoretical and experimental understanding of strangeness production for ultra-relativistic heavy ion collisions.
Date: February 16, 2006
Creator: Samios, N.
Object Type: Article
System: The UNT Digital Library
Revisiting the total ion yield x-ray absorption spectra of liquid water microjets (open access)

Revisiting the total ion yield x-ray absorption spectra of liquid water microjets

Measurements of the total ion yield (TIY) x-ray absorption spectrum (XAS) of liquid water by Wilson et al. (2002 J. Phys.: Condens. Matter 14 L221 and 2001 J. Phys. Chem. B 105 3346) have been revisited in light of new experimental and theoretical efforts by our group. Previously, the TIY spectrum was interpreted as a distinct measure of the electronic structure of the liquid water surface. However, our new results indicate that the previously obtained spectrum may have suffered from as yet unidentified experimental artifacts. Although computational results indicate that the liquid water surface should exhibit a TIY-XAS that is fundamentally distinguishable from the bulk liquid XAS, the new experimental results suggest that the observable TIY-XAS is actually nearly identical in appearance to the total electron yield (TEY-)XAS, which is a bulk probe. This surprising similarity between the observed TIY-XAS and TEY-XAS likely results from large contributions from x-ray induced electron stimulated desorption of ions, and does not necessarily indicate that the electronic structure of the bulk liquid and liquid surface are identical.
Date: February 16, 2008
Creator: Saykally, Richard J; Cappa, Chris D.; Smith, Jared D.; Wilson, Kevin R. & Saykally, Richard J.
Object Type: Article
System: The UNT Digital Library
Micromechanical characterization tools for highly-filled polymers (open access)

Micromechanical characterization tools for highly-filled polymers

We are attempting to characterize and model the micromechanical response of highly-filled polymers. In this class of materials, the continuous plastic binder used to bond the highly-filled material dominates the observed viscoelastic response. As a result, realistic lifetime analysis of these materials will require a thorough understanding of the contribution of the plastic binder. Laboratory applications of these materials include plastic bonded explosives, propellants, a variety of specialized filled organic materials for stockpile systems, and highly filled epoxy dielectric materials for the National Ignition Facility. We have explored numerous techniques to characterize the local microstructure of plastic bonded explosives. However, insufficient funding was obtained to bring these technologies to maturity, nevertheless our present tool set is significantly better than 2 years ago. We have also made some progress in developing an appropriate micromechanical constitutive modeling framework, based on a finite element method incorporating a cohesive zone model to represent the binder contribution within a Voronoi tesselation mesh structure for the PBX grains. A second modeling approach was used to incorporate analytical micromechanics (generalized self-consistent schemes). However, preliminary theoretical analysis strongly suggested that this approach would be invalid for such extremely high-filled systems like PBX.
Date: February 16, 2000
Creator: Groves, S; DeTeresa, S; Cunningham, B; Ciarlo, D; Allen, D; Clayton, K et al.
Object Type: Report
System: The UNT Digital Library
High-Energy Neutron Imaging Development at LLNL (open access)

High-Energy Neutron Imaging Development at LLNL

We are proceeding with the development of a high-energy (10 MeV) neutron imaging system for use as an inspection tool in nuclear stockpile stewardship applications. Our goal is to develop and deploy an imaging system capable of detecting cubic-mm-scale voids, cracks or other significant structural defects in heavily-shielded low-Z materials within nuclear device components. The final production-line system will be relatively compact (suitable for use in existing facilities within the DOE complex) and capable of acquiring both radiographic and tomographic (CT) images. In this report, we will review our recent programmatic accomplishments, focusing primarily on progress made in FY04. The design status of the high-intensity, accelerator-driven neutron source and large-format imaging detector associated with the system will be discussed and results from a recent high-energy neutron imaging experiment conducted at the Ohio University Accelerator Laboratory (OUAL) will also be presented.
Date: February 16, 2005
Creator: Hall, J. M.; Rusnak, B. & Shen, S.
Object Type: Report
System: The UNT Digital Library
Developing the Manufacturing Process for Hylene MP Curing Agent (open access)

Developing the Manufacturing Process for Hylene MP Curing Agent

This report details efforts to scale-up and re-establish the manufacturing process for the curing agent known as Hylene MP. First, small scale reactions were completed with varying conditions to determine key drivers for yielding high quality product. Once the optimum conditions were determined on the small scale, the scaled-up process conditions were determined. New equipment was incorporated into the manufacturing process to create a closed production system and improve chemical exposure controls and improve worker safety. A safe, efficient manufacturing process was developed to manufacture high quality Hylene MP in large quantities.
Date: February 16, 2009
Creator: Eastwood, Eric
Object Type: Report
System: The UNT Digital Library
Experimental and Sampling Design for the INL-2 Sample Collection Operational Test (open access)

Experimental and Sampling Design for the INL-2 Sample Collection Operational Test

This report describes the experimental and sampling design developed to assess sampling approaches and methods for detecting contamination in a building and clearing the building for use after decontamination. An Idaho National Laboratory (INL) building will be contaminated with BG (Bacillus globigii, renamed Bacillus atrophaeus), a simulant for Bacillus anthracis (BA). The contamination, sampling, decontamination, and re-sampling will occur per the experimental and sampling design. This INL-2 Sample Collection Operational Test is being planned by the Validated Sampling Plan Working Group (VSPWG). The primary objectives are: 1) Evaluate judgmental and probabilistic sampling for characterization as well as probabilistic and combined (judgment and probabilistic) sampling approaches for clearance, 2) Conduct these evaluations for gradient contamination (from low or moderate down to absent or undetectable) for different initial concentrations of the contaminant, 3) Explore judgment composite sampling approaches to reduce sample numbers, 4) Collect baseline data to serve as an indication of the actual levels of contamination in the tests. A combined judgmental and random (CJR) approach uses Bayesian methodology to combine judgmental and probabilistic samples to make clearance statements of the form "X% confidence that at least Y% of an area does not contain detectable contamination” (X%/Y% clearance statements). The INL-2 …
Date: February 16, 2009
Creator: Piepel, Gregory F.; Amidan, Brett G. & Matzke, Brett D.
Object Type: Report
System: The UNT Digital Library
HANFORD DOUBLE SHELL TANK (DST) THERMAL & SEISMIC PROJECT INCREASED LIQUID LEVEL ANALYSIS FOR 241-AP TANK FARMS (open access)

HANFORD DOUBLE SHELL TANK (DST) THERMAL & SEISMIC PROJECT INCREASED LIQUID LEVEL ANALYSIS FOR 241-AP TANK FARMS

The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the SDT System at Hanford. The "Double-Shell Tank (DST) Integrity Project - DST Thermal and Seismic Project" is in support of Tri-Party Agreement Milestone M-48-14.
Date: February 16, 2007
Creator: Mackey, T. C.; Deibler, J. E.; Johnson, K. I.; Pilli, S. P.; Karri, N. K.; Rinker, M. W. et al.
Object Type: Report
System: The UNT Digital Library
The SEMATECH Berkeley microfield exposure tool: learning a the 22-nm node and beyond (open access)

The SEMATECH Berkeley microfield exposure tool: learning a the 22-nm node and beyond

Microfield exposure tools (METs) continue to playa dominant role in the development of extreme ultraviolet (EUV) resists. One of these tools is the SEMATECH Berkeley 0.3-NA MET operating as a SEMATECH resist and mask test center. Here we present an update summarizing the latest resist test and characterization results. The relatively small numerical aperture and limited illumination settings expected from 1st generation EUV production tools make resist resolution a critical issue even at the 32-nm node. In this presentation, sub 22 nm half pitch imaging results of EUV resists are reported. We also present contact hole printing at the 30-nm level. Although resist development has progressed relatively well in the areas of resolution and sensitivity, line-edge-roughness (LER) remains a significant concern. Here we present a summary of recent LER performance results and consider the effect of system-level contributors to the LER observed from the SEMA TECH Berkeley microfield tool.
Date: February 16, 2009
Creator: Naulleau, Patrick; Anderson, Christopher; Baclea-an, Lorie-Mae; Denham, Paul; George, Simi; Goldberg, Kenneth A. et al.
Object Type: Article
System: The UNT Digital Library
Selective Organic and Organometallic Reactions in Water-Soluble Host-Guest Supramolecular Systems (open access)

Selective Organic and Organometallic Reactions in Water-Soluble Host-Guest Supramolecular Systems

Inspired by the efficiency and selectivity of enzymes, synthetic chemists have designed and prepared a wide range of host molecules that can bind smaller molecules with their cavities; this area has become known as 'supramolecular' or 'host-guest' chemistry. Pioneered by Lehn, Cram, Pedersen, and Breslow, and followed up by a large number of more recent investigators, it has been found that the chemical environment in each assembly - defined by the size, shape, charge, and functional group availability - greatly influences the guest-binding characteristics of these compounds. In contrast to the large number of binding studies that have been carried out in this area, the exploration of chemistry - especially catalytic chemistry - that can take place inside supramolecular host cavities is still in its infancy. For example, until the work described here was carried out, very few examples of organometallic reactivity inside supramolecular hosts were known, especially in water solution. For that reason, our group and the group directed by Kenneth Raymond decided to take advantage of our complementary expertise and attempt to carry out metal-mediated C-H bond activation reactions in water-soluble supramolecular systems. This article begins by providing background from the Raymond group in supramolecular coordination chemistry and …
Date: February 16, 2008
Creator: Pluth, Michael D.; Raymond, Kenneth N. & Bergman, Robert G.
Object Type: Report
System: The UNT Digital Library
O(N) complexity algorithms for First-Principles Electronic Structure Calculations (open access)

O(N) complexity algorithms for First-Principles Electronic Structure Calculations

The fundamental equation governing a non-relativistic quantum system of N particles is the time-dependant Schroedinger Equation [Schroedinger, 1926]. In 1965, Kohn and Sham proposed to replace this original many-body problem by an auxiliary independent-particles problem that can be solved more easily (Density Functional Theory). Solving this simplified problem requires to find the subspace of dimension N spanned by the N eigenfunctions {Psi}{sub i} corresponding to the N lowest eigenvalues {var_epsilon}{sub i} of a non-linear Hamiltonian operator {cflx H} determined from first-principles. From the solution of the Kohn-Sham equations, forces acting on atoms can be derived to optimize geometries and simulate finite temperature phenomenon by molecular dynamics. This technique is used at LLNL to determine the Equation of State of various materials, and to study biomolecules and nanomaterials.
Date: February 16, 2007
Creator: Fattebert, J. L.
Object Type: Report
System: The UNT Digital Library
Parallel auxiliary space AMG for definite Maxwell problems (open access)

Parallel auxiliary space AMG for definite Maxwell problems

Motivated by the needs of large multi-physics simulation codes, we are interested in algebraic solvers for the linear systems arising in time-domain electromagnetic simulations. Our focus is on finite element discretization, and we are developing scalable parallel preconditioners which employ only fine-grid information, similar to algebraic multigrid (AMG) for diffusion problems. In the last few years, the search for efficient algebraic preconditioners for H(curl) bilinear forms has intensified. The attempts to directly construct AMG methods had some success, see [12, 1, 7]. Exploiting available multilevel methods on auxiliary mesh for the same bilinear form led to efficient auxiliary mesh preconditioners to unstructured problems as shown in [4, 8]. A computationally more attractive approach was recently proposed by Hiptmair and Xu [5]. In contrast to the auxiliary mesh idea, the method in [5] uses a nodal H{sup 1}-conforming auxiliary space on the same mesh. This significantly simplifies the computation of the corresponding interpolation operator. In the present talk, we consider several options for constructing unstructured mesh AMG preconditioners for H(curl) problems and report a summary of computational results from [10, 9]. Our approach is slightly different than the one from [5], since we apply AMG directly to variationally constructed coarse-grid operators, …
Date: February 16, 2007
Creator: Kolev, T V & Vassilevski, P S
Object Type: Article
System: The UNT Digital Library
Orbiter Composite Overwrapped Pressure Vessels (open access)

Orbiter Composite Overwrapped Pressure Vessels

None
Date: February 16, 2005
Creator: DeTeresa, S
Object Type: Report
System: The UNT Digital Library
Thermal Conductivity of Ordered Molecular Water (open access)

Thermal Conductivity of Ordered Molecular Water

We use molecular dynamics simulation to investigate thermal transport characteristics of water with various degree of orientational and translational order induced by the application of an electric field. We observe that orientational ordering of the water dipole moments has a minor effect on the thermal conductivity. However, electric-field induced crystallization and associated translational order results in approximately a 3-fold increase of thermal conductivity with respect to the base water, i.e., to values comparable with those characterizing ice crystal structures.
Date: February 16, 2006
Creator: Evans, W; Fish, J & Keblinski, P
Object Type: Report
System: The UNT Digital Library
Laser-Matter Interactions with a 527 nm Drive (open access)

Laser-Matter Interactions with a 527 nm Drive

The primary goal of this Exploratory Research is to develop an understanding of laser-matter interactions with 527-nm light (2{omega}) for studies of interest to numerous Laboratory programs including inertial confinement fusion (ICF), material strength, radiation transport, and hydrodynamics. In addition, during the course of this work we will develop the enabling technology and prototype instrumentation to diagnose a high fluence laser beam for energy, power, and near field intensity profile at 2{omega}. Through this Exploratory Research we have established an extensive experimental and modeling data base on laser-matter interaction with 527 nm laser light (2{omega}) in plasma conditions of interest to numerous Laboratory programs. The experiments and the laser-plasma interaction modeling using the code pF3D have shown intensity limits and laser beam conditioning requirements for future 2{omega} laser operations and target physics experiments on the National Ignition Facility (NIF). These findings have set requirements for which present radiation-hydrodynamic simulations indicate the successful generation of relevant pressure regimes in future 2{omega} experiments. To allow these experiments on the NIF, optics and optical mounts were prepared for the 18mm Second Harmonic Generation Crystal (SHG crystal) that would provide the desired high conversion efficiency from 1{omega} to 2{omega}. Supporting experimental activities on NIF …
Date: February 16, 2007
Creator: Glenzer, S; Niemann, C; Witman, P; Wegner, P; Mason, D; Haynam, C et al.
Object Type: Report
System: The UNT Digital Library
3D Vectorial Time Domain Computational Integrated Photonics (open access)

3D Vectorial Time Domain Computational Integrated Photonics

The design of integrated photonic structures poses considerable challenges. 3D-Time-Domain design tools are fundamental in enabling technologies such as all-optical logic, photonic bandgap sensors, THz imaging, and fast radiation diagnostics. Such technologies are essential to LLNL and WFO sponsors for a broad range of applications: encryption for communications and surveillance sensors (NSA, NAI and IDIV/PAT); high density optical interconnects for high-performance computing (ASCI); high-bandwidth instrumentation for NIF diagnostics; micro-sensor development for weapon miniaturization within the Stockpile Stewardship and DNT programs; and applications within HSO for CBNP detection devices. While there exist a number of photonics simulation tools on the market, they primarily model devices of interest to the communications industry. We saw the need to extend our previous software to match the Laboratory's unique emerging needs. These include modeling novel material effects (such as those of radiation induced carrier concentrations on refractive index) and device configurations (RadTracker bulk optics with radiation induced details, Optical Logic edge emitting lasers with lateral optical inputs). In addition we foresaw significant advantages to expanding our own internal simulation codes: parallel supercomputing could be incorporated from the start, and the simulation source code would be accessible for modification and extension. This work addressed Engineering's Simulation …
Date: February 16, 2007
Creator: Kallman, J S; Bond, T C; Koning, J M & Stowell, M L
Object Type: Report
System: The UNT Digital Library
3-D sedimentological and geophysical studies of clastic reservoir analogs: Facies architecture, reservoir properties, and flow behavior within delta front facies elements of the Cretaceous Wall Creek Member, Frontier Formation, Wyoming (open access)

3-D sedimentological and geophysical studies of clastic reservoir analogs: Facies architecture, reservoir properties, and flow behavior within delta front facies elements of the Cretaceous Wall Creek Member, Frontier Formation, Wyoming

This project examined the internal architecture of delta front sandstones at two locations within the Turonian-age Wall Creek Member of the Frontier Formation, in Wyoming. The project involved traditional outcrop field work integrated with core-data, and 2D and 3D ground penetrating radar (GPR) imaging from behind the outcrops. The fluid-flow engineering work, handled through a collaborative grant given to PI Chris White at LSU, focused on effects on fluid flow of late-stage calcite cement nodules in 3D. In addition to the extensive field component, the work funded 2 PhD students (Gani and Lee) and resulted in publication of 10 technical papers, 17 abstracts, and 4 internal field guides. PI Bhattacharya also funded an additional 3 PhD students that worked on the Wall Creek sandstone funded separately through an industrial consortium, two of whom graduated in the fall 2006 ((Sadeque and Vakarelov). These additional funds provided significant leverage to expand the work to include a regional stratigraphic synthesis of the Wall Creek Member of the Frontier Formation, in addition to the reservoir-scale studies that DOE directly funded. Awards given to PI Bhattacharya included the prestigious AAPG Distinguished Lecture Award, which involved a tour of about 25 Universities and Geological Societies in …
Date: February 16, 2007
Creator: Bhattacharya, Janok P. & McMechan, George A.
Object Type: Report
System: The UNT Digital Library
Cost of Power Interruptions to Electricity Consumers in the United States (U.S.) (open access)

Cost of Power Interruptions to Electricity Consumers in the United States (U.S.)

The massive electric power blackout in the northeastern U.S.and Canada on August 14-15, 2003 catalyzed discussions about modernizingthe U.S. electricity grid. Industry sources suggested that investments of$50 to $100 billion would be needed. This work seeks to better understandan important piece of information that has been missing from thesediscussions: What do power interruptions and fluctuations in powerquality (power-quality events) cost electricity consumers? We developed abottom-up approach for assessing the cost to U.S. electricity consumersof power interruptions and power-quality events (referred to collectivelyas "reliability events"). The approach can be used to help assess thepotential benefits of investments in improving the reliability of thegrid. We developed a new estimate based on publicly availableinformation, and assessed how uncertainties in these data affect thisestimate using sensitivity analysis.
Date: February 16, 2006
Creator: Hamachi LaCommare, Kristina & Eto, Joseph H.
Object Type: Article
System: The UNT Digital Library
The Back End of the Fuel Cycle Moves Front and Center (open access)

The Back End of the Fuel Cycle Moves Front and Center

For many years, the commercial nuclear business has remained relatively stable in many ways. The introduction of new plants, the spread to new countries, and the development of key elements of the fuel cycle such as enrichment, reprocessing and waste disposal have been quite modest. That is unlikely to be the case in the coming years. A number of events and trends are becoming increasingly apparent and are cause for both opportunity and caution: (1) New nuclear power plant orders are likely to grow and spread, particularly in the developing world, e.g. China and India. (2) The growing recognition that the developing world will be a major competitor for limited energy resources is raising awareness in the developed world regarding concerns for future energy security. (3) Clearer evidence of the effects of greenhouse gas emissions on global warming, largely from the burning of fossil fuels, is creating more attention on the environmental benefits of nuclear power. (4) The last decade has shown unequivocal evidence of countries lying, cheating on their NPT obligation, and covertly carrying out nuclear weapons-related activities. Some have suggested their presumed need for a domestic nuclear fuel cycle as a rationale to pursue enrichment and/or reprocessing capabilities, …
Date: February 16, 2006
Creator: Isaacs, T & Choi, J
Object Type: Article
System: The UNT Digital Library
Triple-axis X-ray Reciprocal Space Mapping of In(y)Ga(1-y)As Thermophotovoltaic Diodes Grown on (100) InP Substrates (open access)

Triple-axis X-ray Reciprocal Space Mapping of In(y)Ga(1-y)As Thermophotovoltaic Diodes Grown on (100) InP Substrates

Analysis of the composition, strain-relaxation, layer-tilt, and the crystalline quality of In{sub y}Ga{sub 1-y}As/InP{sub 1-x}As{sub x} thermophotovoltaic (TPV) diodes grown by metal organic vapor phase epitaxy (MOVPE) is demonstrated using triple-axis x-ray reciprocal space mapping techniques. In{sub 0.53}Ga{sub 0.47}As (E{sub gap} = 0.74eV) n/p junction diodes are grown lattice matched (LM) to InP substrates and lattice mismatched (LMM) In{sub 0.67}Ga{sub 0.33}As (E{sub gap} = 0.6eV) TPV diodes are grown on three-step InP{sub 1-x}As{sub x} (0 < x < 0.32) buffer layers on InP substrates. X-ray reciprocal space maps about the symmetric (400) and asymmetric (533) reciprocal lattice points (RELPs) determine the in-plane and out-of-plane lattice parameters and strain of the In{sub y}Ga{sub 1-y}As TPV active layer and underlying InP{sub 1-x}As{sub x} buffers. Triple-axis x-ray rocking curves about the LMM In{sub 0.67}Ga{sub 0.33}As RELP show an order of magnitude increase of its full width at half maximum (FWHM) compared to that from the LM In{sub 0.53}Ga{sub 0.47}As (250asec vs. 30asec). Despite the significant RELP broadening the photovoltaic figure of merits show that the electronic quality of the LMM In{sub 0.67}Ga{sub 0.33}As approaches that of the lattice matched diode material. This indicates that misfit-related crystalline imperfections are not dominating the photovoltaic response …
Date: February 16, 2006
Creator: Dashiell, M; Ehsani, H; Sander, P; Newman, F; Wang, C; Shellenbarger, Z et al.
Object Type: Report
System: The UNT Digital Library
Final report on the project entitled: Highly Preheated Combustion Air System with/without Oxygen Enrichment for Metal Processing Furnaces (open access)

Final report on the project entitled: Highly Preheated Combustion Air System with/without Oxygen Enrichment for Metal Processing Furnaces

This work develops and demonstrates a laboratory-scale high temperature natural gas furnace that can operate with/without oxygen enrichment to significantly improve energy efficiency and reduce emissions. The laboratory-scale is 5ft in diameter & 8ft tall. This furnace was constructed and tested. This report demonstrates the efficiency and pollutant prevention capabilities of this test furnace. The project also developed optical detection technology to control the furnace output.
Date: February 16, 2007
Creator: Atreya, Arvind
Object Type: Report
System: The UNT Digital Library
HANFORD DOUBLE SHELL TANK (DST) THERMAL & SEISMIC PROJECT DYTRAN BENCHMARK ANALYSIS OF SEISMICALLY INDUCED FLUID STRUCTURE INTERACTION IN FLAT TOP TANKS (open access)

HANFORD DOUBLE SHELL TANK (DST) THERMAL & SEISMIC PROJECT DYTRAN BENCHMARK ANALYSIS OF SEISMICALLY INDUCED FLUID STRUCTURE INTERACTION IN FLAT TOP TANKS

The work reported in this document was performed in support of a project entitled ''Double-Shell Tank (DST) Integrity Project - DST Thermal and Seismic Analyses''. The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the DST System at Hanford. The work described herein was performed in support of the seismic analysis of the DSTs. The thermal and operating loads analysis of the DSTs is documented in Rinker et al. (2004). The work herein was motivated by review comments from a Project Review Meeting held on March 20-21, 2006. One of the recommendations from that meeting was that the effects of the interaction between the tank liquid and the roof be further studied (Rinker, Deibler, Johnson, Karri, Pilli, Abatt, Carpenter, and Hendrix - Appendix E of RPP-RPT-28968, Rev. 1). The reviewers recommended that solutions be obtained for seismic excitation of flat roof tanks containing liquid with varying headspace between the top of the liquid and the tank roof. It was recommended that the solutions be compared with simple, approximate procedures described in BNL (1995) and Malhotra (2005). This report documents the results of the requested studies and compares the predictions of Dytran simulations to …
Date: February 16, 2007
Creator: MACKEY, T.C.
Object Type: Report
System: The UNT Digital Library
Measurement of the Cosmic Ray and Neutrino-Induced Muon Flux at the Sudbury Neutrino Observatory (open access)

Measurement of the Cosmic Ray and Neutrino-Induced Muon Flux at the Sudbury Neutrino Observatory

Results are reported on the measurement of the atmospheric neutrino-induced muon flux at a depth of 2 kilometers below the Earth's surface from 1229 days of operation of the Sudbury Neutrino Observatory (SNO). By measuring the flux of through-going muons as a function of zenith angle, the SNO experiment can distinguish between the oscillated and un-oscillated portion of the neutrino flux. A total of 514 muon-like events are measured between -1 {le} cos {theta}{sub zenith} 0.4 in a total exposure of 2.30 x 10{sup 14} cm{sup 2} s. The measured flux normalization is 1.22 {+-} 0.09 times the Bartol three-dimensional flux prediction. This is the first measurement of the neutrino-induced flux where neutrino oscillations are minimized. The zenith distribution is consistent with previously measured atmospheric neutrino oscillation parameters. The cosmic ray muon flux at SNO with zenith angle cos {theta}{sub zenith} > 0.4 is measured to be (3.31 {+-} 0.01 (stat.) {+-} 0.09 (sys.)) x 10{sup -10} {micro}/s/cm{sup 2}.
Date: February 16, 2009
Creator: SNO Collaboration; Aharmim, B.; Ahmed, S. N.; Andersen, T. C.; Anthony, A. E.; Barros, N. et al.
Object Type: Article
System: The UNT Digital Library
Chromaticity Measurements Using Phase Modulated RF and Vector Signal Analyzers (open access)

Chromaticity Measurements Using Phase Modulated RF and Vector Signal Analyzers

Chromaticity measurements are usually done by changing the energy of the beam by a known amount and measuring the change in betatron tune with a spectrum analyzer. The energy change is done by adjusting the RF frequency. The change in RF frequency is made large enough so that the change in betatron tune can be seen. If synchrotron motion is present in the beam, then measuring the change in betatron tune can be difficult. This note will outline a method to measure the change in betatron tune by phase-modulating the RF and measuring the phase modulated betatron spectrum Extremely small resolution bandwidths are available on modern vector signal analyzers. A small resolution bandwidth is equivalent to measuring the chromaticity many times and averaging the results. This would permit much smaller shifts in betatron tunes to be measured. The phase-modulated signal consists of sidebands whose amplitudes are given by Bessel functions. The complication of the Bessel functions can be removed if the vector signal analyzer is capable of phase demodulation. The sign of the chromaticity can be determined by observing the modulation spectrum at both betatron sidebands.
Date: February 16, 2001
Creator: McGinnis, Dave
Object Type: Report
System: The UNT Digital Library