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Sharing atrocity stories in hospice: A study of niceness message strategies in interdisciplinary team meetings (open access)

Sharing atrocity stories in hospice: A study of niceness message strategies in interdisciplinary team meetings

Article on sharing atrocity stories in hospice and a study of niceness message strategies in interdisciplinary team meetings.
Date: July 1, 2011
Creator: Wittenberg-Lyles, Elaine; Oliver, Debra Parker; Demiris, George & Cunningham, Cody P.
System: The UNT Digital Library
Using EnergyPlus to Perform Dehumidification Analysis on Building America Homes: Preprint (open access)

Using EnergyPlus to Perform Dehumidification Analysis on Building America Homes: Preprint

A parametric study was conducted using EnergyPlus version 6.0 to investigate humidity issues on a typical mid-1990s reference home, a 2006 International Energy Conservation Code home, and a high-performance home in a hot-humid climate. The impacts of various dehumidification equipment and controls are analyzed on the high performance home. The study examined the combined effects of infiltration and mechanical ventilation with balanced and unbalanced mechanical ventilation systems. Indoor relative humidity excursions were examined; specifically, the number of excursions, average excursion length, and maximum excursion length. Space relative humidity, thermal comfort, and whole-house source energy consumption were analyzed for indoor relative humidity set points of 50%, 55%, and 60%. The study showed and explained why similar trends of high humidity were observed in all three homes regardless of energy efficiency, and why humidity problems are not necessarily unique in high-performance homes. Thermal comfort analysis indicated that occupants are unlikely to notice indoor humidity problems. The study confirmed that supplemental dehumidification should be provided to maintain space relative humidity below 60% in a hot-humid climate.
Date: March 1, 2011
Creator: Fang, X.; Winkler, J. & Christensen, D.
System: The UNT Digital Library
Molecular analysis of the metabolic rates of discrete subsurface populations of sulfate reducers (open access)

Molecular analysis of the metabolic rates of discrete subsurface populations of sulfate reducers

Elucidating the in situ metabolic activity of phylogenetically diverse populations of sulfate-reducing microorganisms that populate anoxic sedimentary environments is key to understanding subsurface ecology. Previous pure culture studies have demonstrated that transcript abundance of dissimilatory (bi)sulfite reductase genes is correlated with the sulfate reducing activity of individual cells. To evaluate whether expression of these genes was diagnostic for subsurface communities, dissimilatory (bi)sulfite reductase gene transcript abundance in phylogenetically distinct sulfate-reducing populations was quantified during a field experiment in which acetate was added to uranium-contaminated groundwater. Analysis of dsrAB sequences prior to the addition of acetate indicated that Desulfobacteraceae, Desulfobulbaceae, and Syntrophaceae-related sulfate reducers were the most abundant. Quantifying dsrB transcripts of the individual populations suggested that Desulfobacteraceae initially had higher dsrB transcripts per cell than Desulfobulbaceae or Syntrophaceae populations, and that the activity of Desulfobacteraceae increased further when the metabolism of dissimilatory metal reducers competing for the added acetate declined. In contrast, dsrB transcript abundance in Desulfobulbaceae and Syntrophaceae remained relatively constant, suggesting a lack of stimulation by added acetate. The indication of higher sulfate-reducing activity in the Desulfobacteraceae was consistent with the finding that Desulfobacteraceae became the predominant component of the sulfate-reducing community. Discontinuing acetate additions resulted in a …
Date: April 1, 2011
Creator: Miletto, M.; Williams, K.H.; N'Guessan, A.L. & Lovley, D.R.
System: The UNT Digital Library
Overview of the US-Japan collaborative investigation on hydrogen isotope retention in neutron-irradiated and ion-damaged tungsten (open access)

Overview of the US-Japan collaborative investigation on hydrogen isotope retention in neutron-irradiated and ion-damaged tungsten

Plasma-facing components (PFCs) will be exposed to 14 MeV neutrons from deuterium-tritium (D-T) fusion reactions, and tungsten, a candidate PFC for the divertor in ITER, is expected to receive a neutron dose of 0.7 displacement per atom (dpa) by the end of operation in ITER. The effect of neutron-irradiation damage has been mainly simulated using high-energy ion bombardment. While this prior database of results is quite valuable for understanding the behavior of hydrogen isotopes in PFCs, it does not encompass the full range of effects that must be considered in a practical fusion environment due to short penetration depth, damage gradient, high damage rate, and high PKA energy spectrum of the ion bombardment. In addition, neutrons change the elemental composition via transmutations, and create a high radiation environment inside PFCs, which influence the behavior of hydrogen isotope in PFCs, suggesting the utilization of fission reactors is necessary for neutron irradiation. Therefore, the effort to correlate among high-energy ions, fission neutrons, and fusion neutrons is crucial for accurately estimating tritium retention under a neutron-irradiation environment. Under the framework of the US-Japan TITAN program, tungsten samples (99.99 at. % purity from A.L.M.T. Co.) were irradiated by neutron in the High Flux Isotope …
Date: September 1, 2011
Creator: Shimada, Masashi; Hatano, Y.; Oya, Y.; Oda, T.; Hara, M.; Cao, G. et al.
System: The UNT Digital Library
Magnetic Alignment of Pulsed Solenoids Using the Pulsed Wire Method (open access)

Magnetic Alignment of Pulsed Solenoids Using the Pulsed Wire Method

A unique application of the pulsed-wire measurement method has been implemented for alignment of 2.5 T pulsed solenoid magnets. The magnetic axis measurement has been shown to have a resolution of better than 25 {micro}m. The accuracy of the technique allows for the identification of inherent field errors due to, for example, the winding layer transitions and the current leads. The alignment system is developed for the induction accelerator NDCX-II under construction at LBNL, an upgraded Neutralized Drift Compression experiment for research on warm dense matter and heavy ion fusion. Precise alignment is essential for NDCX-II, since the ion beam has a large energy spread associated with the rapid pulse compression such that misalignments lead to corkscrew deformation of the beam and reduced intensity at focus. The ability to align the magnetic axis of the pulsed solenoids to within 100 pm of the induction cell axis has been demonstrated.
Date: April 1, 2011
Creator: Arbelaez, D.; Madur, A.; Lipton, T. M.; Waldron, W. L. & Kwan, J. W.
System: The UNT Digital Library
Intent, Capability and Opportunity: A Holistic Approach to Addressing Proliferation as a Risk Management Issue (open access)

Intent, Capability and Opportunity: A Holistic Approach to Addressing Proliferation as a Risk Management Issue

Currently, proliferation risk assessment models are designed to evaluate only a portion of the overall risk, focusing exclusively on either technological or social factors to determine the extent of a threat. Many of these models are intended to act as a means of predicting proliferation potential rather than assessing the system as a whole, ignoring the ability to enhance mitigating factors and manage, rather just establish the presence of, the threat. While the information garnered through these forms of analysis is necessary, it remains incomplete. By incorporating political, social, economic and technical capabilities as well as human factors such as intent into a single, multi-faceted risk management model, proliferation risk can be evaluated more effectively. Framing this information around how to improve and expand the Regime already in place and establishing where there are gaps in the system allows for a more complete approach to risk management, mitigation and resource allocation. The research conducted here seeks to combine all three elements (intent, capability and opportunity) in a comprehensive evaluation which incorporates an assessment of state-level variables, possible proliferation pathways and technical capability. Each portion of the analysis is carried out independently then combined to illustrate the full scope of a …
Date: July 1, 2011
Creator: Rynes, Amanda & Bjornard, Trond
System: The UNT Digital Library
Compression Waves and Phase Plots: Simulations (open access)

Compression Waves and Phase Plots: Simulations

Compression wave analysis started nearly 50 years ago with Fowles. Coperthwaite and Williams gave a method that helps identify simple and steady waves. We have been developing a method that gives describes the non-isentropic character of compression waves, in general. One result of that work is a simple analysis tool. Our method helps clearly identify when a compression wave is a simple wave, a steady wave (shock), and when the compression wave is in transition. This affects the analysis of compression wave experiments and the resulting extraction of the high-pressure equation of state.
Date: August 1, 2011
Creator: Orlikowski, D. & Minich, R.
System: The UNT Digital Library
Calibrating transport lines using LOCO techniques (open access)

Calibrating transport lines using LOCO techniques

With the 12GeV upgrade underway at CEBAF, there is a need to re-characterize the beamlines after the modifications made to it to accommodate running at higher energies. We present a linear perturbation approach to calibrating the optics model of transport lines. This method is adapted from the LOCO method in use for storage rings. We consider the effect of quadrupole errors, dipole construction errors as well as beam position monitors and correctors calibrations. The ideal model is expanded to first order in Taylor series of the quadrupole errors. A set of difference orbits obtained by exciting the correctors along the beamline is taken, yielding the measured response matrix. An iterative procedure is invoked and the quadrupole errors as well as beam position monitors and corrector calibration factors are obtained. Here we present details of the method and results of first measurements at CEBAF in early 2011.
Date: September 1, 2011
Creator: Roblin, Yves
System: The UNT Digital Library
Loads Analysis of Several Offshore Floating Wind Turbine Concepts (open access)

Loads Analysis of Several Offshore Floating Wind Turbine Concepts

This paper presents a comprehensive dynamic-response analysis of six offshore floating wind turbine concepts.
Date: October 1, 2011
Creator: Robertson, A. N. & Jonkman, J. M.
System: The UNT Digital Library
Search for $B_s \to \mu^+\mu^-$ and $B_d \to \mu^+\mu^-$ Decays with CDF II (open access)

Search for $B_s \to \mu^+\mu^-$ and $B_d \to \mu^+\mu^-$ Decays with CDF II

A search has been performed for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays using 7 fb{sup -1} of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B{sup 0} candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 6.0 x 10{sup -9} at 95% confidence level. We observe an excess of B{sub s}{sup 0} candidates. The probability that the background processes alone could produce such an excess or larger is 0.27%. The probability that the combination of background and the expected standard model rate of B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} could produce such an excess or larger is 1.9%. These data are used to determine {Beta}(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) = (1.8{sub -0.9}{sup +1.1}) x 10{sup -8} and provide an upper limit of {Beta}(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 4.0 x 10{sup -8} at 95% confidence level.
Date: July 1, 2011
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Alvarez Gonzalez, B.; Phys., /Oviedo U. /Cantabria Inst. of; Amerio, S.; /INFN, Padua et al.
System: The UNT Digital Library
Studies of Single Electroweak Bosons at the Tevatron (open access)

Studies of Single Electroweak Bosons at the Tevatron

Tests of the Standard Model with Electroweak Physics have been performed over many decades. In these proceedings, we present several analyses from the Tevatron involving single W or Z bosons. Electroweak (EW) physics has been crucial for discovering and confirming many aspects of the Standard Model (SM). Furthermore, through radiative corrections EW physics allows for indirect views of heavy particles. Indeed the relationship between W boson, top quark, and Higgs boson masses is instrumental in predicting at what mass the Higgs boson may finally be found. In these proceedings, we present several recent analyses from the Tevatron involving single W or Z bosons to test the SM. The Tevatron is a p {bar p} collider at {radical}s = 1.96 TeV located at the Fermi National Accelerator Laboratory. CDF and D0 are its two multi-purpose detectors concentrating on high P{sub T} physics. Both detectors are described in detail elsewhere.
Date: August 1, 2011
Creator: Lyon, Adam L.
System: The UNT Digital Library
Structural Design of a Horizontal-Axis Tidal Current Turbine Composite Blade (open access)

Structural Design of a Horizontal-Axis Tidal Current Turbine Composite Blade

This paper describes the structural design of a tidal composite blade. The structural design is preceded by two steps: hydrodynamic design and determination of extreme loads. The hydrodynamic design provides the chord and twist distributions along the blade length that result in optimal performance of the tidal turbine over its lifetime. The extreme loads, i.e. the extreme flap and edgewise loads that the blade would likely encounter over its lifetime, are associated with extreme tidal flow conditions and are obtained using a computational fluid dynamics (CFD) software. Given the blade external shape and the extreme loads, we use a laminate-theory-based structural design to determine the optimal layout of composite laminas such that the ultimate-strength and buckling-resistance criteria are satisfied at all points in the blade. The structural design approach allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. In addition, certain fabrication criteria are imposed, for example, each composite laminate must be an integral multiple of its constituent ply thickness. In the present effort, the structural design uses only static extreme loads; dynamic-loads-based fatigue design will be addressed in the future. Following the blade design, we compute the …
Date: October 1, 2011
Creator: Bir, G. S.; Lawson, M. J. & Li, Y.
System: The UNT Digital Library
A Hierarchical Security Architecture for Cyber-Physical Systems (open access)

A Hierarchical Security Architecture for Cyber-Physical Systems

Security of control systems is becoming a pivotal concern in critical national infrastructures such as the power grid and nuclear plants. In this paper, we adopt a hierarchical viewpoint to these security issues, addressing security concerns at each level and emphasizing a holistic cross-layer philosophy for developing security solutions. We propose a bottom-up framework that establishes a model from the physical and control levels to the supervisory level, incorporating concerns from network and communication levels. We show that the game-theoretical approach can yield cross-layer security strategy solutions to the cyber-physical systems.
Date: August 1, 2011
Creator: Zhu, Quanyan & Basar, Tamer
System: The UNT Digital Library
Neutrino-nucleus interactions (open access)

Neutrino-nucleus interactions

The study of neutrino oscillations has necessitated a new generation of neutrino experiments that are exploring neutrino-nuclear scattering processes. We focus in particular on charged-current quasi-elastic scattering, a particularly important channel that has been extensively investigated both in the bubble-chamber era and by current experiments. Recent results have led to theoretical reexamination of this process. We review the standard picture of quasi-elastic scattering as developed in electron scattering, review and discuss experimental results, and discuss additional nuclear effects such as exchange currents and short-range correlations that may play a significant role in neutrino-nucleus scattering.
Date: January 1, 2011
Creator: Gallagher, H.; Garvey, G. & Zeller, G. P.
System: The UNT Digital Library
LONG-TERM PERFORMANCE OF SOLID OXIDE STACKS WITH ELECTRODE-SUPPORTED CELLS OPERATING IN THE STEAM ELECTROLYSIS MODE (open access)

LONG-TERM PERFORMANCE OF SOLID OXIDE STACKS WITH ELECTRODE-SUPPORTED CELLS OPERATING IN THE STEAM ELECTROLYSIS MODE

Performance characterization and durability testing have been completed on two five-cell high-temperature electrolysis stacks constructed with advanced cell and stack technologies. The solid oxide cells incorporate a negative-electrode-supported multi-layer design with nickel-zirconia cermet negative electrodes, thin-film yttria-stabilized zirconia electrolytes, and multi-layer lanthanum ferrite-based positive electrodes. The per-cell active area is 100 cm2. The stack is internally manifolded with compliant mica-glass seals. Treated metallic interconnects with integral flow channels separate the cells. Stack compression is accomplished by means of a custom spring-loaded test fixture. Initial stack performance characterization was determined through a series of DC potential sweeps in both fuel cell and electrolysis modes of operation. Results of these sweeps indicated very good initial performance, with area-specific resistance values less than 0.5 ?.cm2. Long-term durability testing was performed with A test duration of 1000 hours. Overall performance degradation was less than 10% over the 1000-hour period. Final stack performance characterization was again determined by a series of DC potential sweeps at the same flow conditions as the initial sweeps in both electrolysis and fuel cell modes of operation. A final sweep in the fuel cell mode indicated a power density of 0.356 W/cm2, with average per-cell voltage of 0.71 V at …
Date: November 1, 2011
Creator: O'Brien, J. E.; O'Brien, R. C.; Zhang, X.; Tao, G. & Butler, B. J.
System: The UNT Digital Library
STUDY ON AIR INGRESS MITIGATION METHODS IN THE VERY HIGH TEMPERATURE GAS COOLED REACTOR (VHTR) (open access)

STUDY ON AIR INGRESS MITIGATION METHODS IN THE VERY HIGH TEMPERATURE GAS COOLED REACTOR (VHTR)

An air-ingress accident followed by a pipe break is considered as a critical event for a very high temperature gas-cooled reactor (VHTR). Following helium depressurization, it is anticipated that unless countermeasures are taken, air will enter the core through the break leading to oxidation of the in-core graphite structure. Thus, without mitigation features, this accident might lead to severe exothermic chemical reactions of graphite and oxygen. Under extreme circumstances, a loss of core structural integrity may occur along with excessive release of radiological inventory. Idaho National Laboratory under the auspices of the U.S. Department of Energy is performing research and development (R&D) that focuses on key phenomena important during challenging scenarios that may occur in the VHTR. Phenomena Identification and Ranking Table (PIRT) studies to date have identified the air ingress event, following on the heels of a VHTR depressurization, as very important (Oh et al. 2006, Schultz et al. 2006). Consequently, the development of advanced air ingress-related models and verification and validation (V&V) requirements are part of the experimental validation plan. This paper discusses about various air-ingress mitigation concepts applicable for the VHTRs. The study begins with identifying important factors (or phenomena) associated with the air-ingress accident by using …
Date: March 1, 2011
Creator: Oh, Chang H.
System: The UNT Digital Library
Energy Use Intensity and its Influence on the Integrated Daylighting Design of a Large Net Zero Energy Building: Preprint (open access)

Energy Use Intensity and its Influence on the Integrated Daylighting Design of a Large Net Zero Energy Building: Preprint

Net-zero energy buildings generate as much energy as they consume and are significant in the sustainable future of building design and construction. The role of daylighting (and its simulation) in the design process becomes critical. In this paper we present the process the National Renewable Energy Laboratory embarked on in the procurement, design, and construction of its newest building, the Research Support Facility (RSF) - particularly the roles of daylighting, electric lighting, and simulation. With a rapid construction schedule, the procurement, design, and construction had to be tightly integrated; with low energy use. We outline the process and measures required to manage a building design that could expect to operate at an efficiency previously unheard of for a building of this type, size, and density. Rigorous simulation of the daylighting and the electric lighting control response was a given, but the oft-ignored disconnect between lighting simulation and whole-building energy use simulation had to be addressed. The RSF project will be thoroughly evaluated for its performance for one year; preliminary data from the postoccupancy monitoring efforts will also be presented with an eye toward the current efficacy of building energy and lighting simulation.
Date: March 1, 2011
Creator: Guglielmetti , R.; Scheib, J.; Pless, S. D.; Torcellini , P. & Petro, R.
System: The UNT Digital Library
Dynamical coupled-channels study of meson production reactions from EBAC@Jlab (open access)

Dynamical coupled-channels study of meson production reactions from EBAC@Jlab

We present the current status of a combined and simultaneous analysis of meson production reactions based on a dynamical coupled-channels (DCC) model, which is conducted at Excited Baryon Analysis Center (EBAC) of Jefferson Lab.
Date: October 1, 2011
Creator: Kamano, Hiroyuki
System: The UNT Digital Library
The nature of the lightest scalar meson, its N_c behaviour and semi-local duality (open access)

The nature of the lightest scalar meson, its N_c behaviour and semi-local duality

One-loop unitarized Chiral Perturbation Theory (UChPT) calculations, suggest a different N{sub c} behaviour for the {sigma} or f{sub 0}(600) and {rho}(770) mesons: while the {rho} meson becomes narrower with N{sub c}, as expected for a {bar q}q meson, the f{sub 0}(600) contribution to the total cross section below 1 GeV becomes less and less important. Here we review our recent work where we have shown, by means of finite energy sum rules, that a different N{sub c} behavior for these resonances may lead to a conflict with semi-local duality for large N{sub c}, since local duality requires a cancellation between the f{sub 0}(600) and {rho}(770) amplitudes. However, UChPT calculations also suggest a subdominant {bar q}q component for the f{sub 0}(600) with a mass above 1 GeV and this can restore semi-local duality, as we show.
Date: December 1, 2011
Creator: JR Pelaez, MR Pennington, J Ruiz de Elvira, DJ Wilson
System: The UNT Digital Library
Dipole corrector magnets for the LBNE beam line (open access)

Dipole corrector magnets for the LBNE beam line

The conceptual design of a new dipole corrector magnet has been thoroughly studied. The planned Long-Baseline Neutrino Experiment (LBNE) beam line will require correctors capable of greater range and linearity than existing correctors, so a new design is proposed based on the horizontal trim dipole correctors built for the Main Injector synchrotron at Fermilab. The gap, pole shape, length, and number of conductor turns remain the same. To allow operation over a wider range of excitations without overheating, the conductor size is increased, and to maintain better linearity, the back leg thickness is increased. The magnetic simulation was done using ANSYS to optimize the shape and the size of the yoke. The thermal performance was also modeled and analyzed.
Date: March 1, 2011
Creator: Yu, M.; Velev, G.; Harding, D. & /Fermilab
System: The UNT Digital Library
RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND (open access)

RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND

Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which …
Date: October 1, 2011
Creator: Farfan, E. & Jannik, T.
System: The UNT Digital Library
Combined CDF and D0 upper limits on $gg\to H\to W^+W^-$ and constraints on the Higgs boson mass in fourth-generation fermion models with up to 8.2 fb$^{-1}$ of data (open access)

Combined CDF and D0 upper limits on $gg\to H\to W^+W^-$ and constraints on the Higgs boson mass in fourth-generation fermion models with up to 8.2 fb$^{-1}$ of data

We combine results from searches by the CDF and D0 Collaborations for a standard model Higgs boson (H) in the processes gg {yields} H {yields} W{sup +}W{sup -} and gg {yields} H {yields} ZZ in p{bar p} collisions at the Fermilab Tevatron Collider at {radical}s = 1.96 TeV. With 8.2 fb{sup -1} of integrated luminosity analyzed at CDF and 8.1 fb{sup -1} at D0, the 95% C.L. upper limit on {sigma}(gg {yields} H) x {Beta}(H {yields} W{sup +}W{sup -}) is 1.01 pb at m{sub H} = 120 GeV, 0.40 pb at m{sub H} = 165 GeV, and 0.47 pb at m{sub H} = 200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% Confidence Level a standard-model-like Higgs boson with a mass between 124 and 286 GeV.
Date: August 1, 2011
Creator: Benjamin, Doug
System: The UNT Digital Library
Unraveling the nature of charge excitations in La2CuO4 with momentum-resolved Cu K-edge resonant inelastic X-ray scattering (open access)

Unraveling the nature of charge excitations in La2CuO4 with momentum-resolved Cu K-edge resonant inelastic X-ray scattering

Results of model calculations using exact diagonalization reveal the orbital character of states associated with different Raman loss peaks in Cu K-edge resonant inelastic X-ray scattering (RIXS) from La{sub 2}CuO{sub 4}. The model includes electronic orbitals necessary to highlight non-local Zhang-Rice singlet, charge transfer and d-d excitations, as well as states with apical oxygen 2p{sub z} character. The dispersion of these excitations is discussed with prospects for resonant final state wave-function mapping. A good agreement with experiments emphasizes the substantial multi-orbital character of RIXS profiles in the energy transfer range 1-6 eV.
Date: March 1, 2011
Creator: Chen, Cheng-Chien
System: The UNT Digital Library
Model-independent analysis of the Fermilab Tevatron turn-by-turn beam position monitor measurements (open access)

Model-independent analysis of the Fermilab Tevatron turn-by-turn beam position monitor measurements

Coherent transverse beam oscillations in the Tevatron were analyzed with the model-independent analysis (MIA) technique. This allowed one to obtain the model-independent values of coupled betatron amplitudes, phase advances, and dispersion function around the ring from a single dipole kick measurement. In order to solve the MIA mode mixing problem which limits the accuracy of determination of the optical functions, we have developed a new technique of rotational MIA mode untangling. The basic idea is to treat each beam position monitor (BPM) as two BPMs separated in a ring by exactly one turn. This leads to a simple criterion of MIA mode separation: the betatron phase advance between any BPM and its counterpart shifted by one turn should be equal to the betatron tune and therefore should not depend on the BPM position in the ring. Furthermore, we describe a MIA-based technique to locate vibrating magnets in a storage ring.
Date: September 1, 2011
Creator: Petrenko, A. V.; /Novosibirsk, IYF; Valishev, A. A.; Lebedev, V. A. & /Fermilab
System: The UNT Digital Library