Development of ITER 15 MA ELMy H-mode Inductive Scenario (open access)

Development of ITER 15 MA ELMy H-mode Inductive Scenario

The poloidal field (PF) coil system on ITER, which provides both feedforward and feedback control of plasma position, shape, and current, is a critical element for achieving mission performance. Analysis of PF capabilities has focused on the 15 MA Q = 10 scenario with a 300-500 s flattop burn phase. The operating space available for the 15 MA ELMy H-mode plasma discharges in ITER and upgrades to the PF coils or associated systems to establish confidence that ITER mission objectives can be reached have been identified. Time dependent self-consistent free-boundary calculations were performed to examine the impact of plasma variability, discharge programming, and plasma disturbances. Based on these calculations a new reference scenario was developed based upon a large bore initial plasma, early divertor transition, low level heating in L-mode, and a late H-mode onset. Equilibrium analyses for this scenario indicate that the original PF coil limitations do not allow low li (<0.8) operation or lower flux states, and the flattop burn durations were predicted to be less than the desired 400 s. This finding motivates the expansion of the operating space, considering several upgrade options to the PF coils. Analysis was also carried out to examine the feedback current …
Date: October 16, 2008
Creator: Kessel, C. E.; Campbell, D.; Gribov, Y.; Saibene, G.; Ambrosino, G.; Casper, T. et al.
Object Type: Article
System: The UNT Digital Library
2006 Oak Ridge National Laboratory Annual Illness and Injury Surveillance Report (open access)

2006 Oak Ridge National Laboratory Annual Illness and Injury Surveillance Report

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: May 16, 2008
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
The L_X-M relation of Clusters of Galaxies (open access)

The L_X-M relation of Clusters of Galaxies

We present a new measurement of the scaling relation between X-ray luminosity and total mass for 17,000 galaxy clusters in the maxBCG cluster sample. Stacking sub-samples within fixed ranges of optical richness, N200, we measure the mean 0.1-2.4 keV X-ray luminosity, <L{sub X}>, from the ROSAT All-Sky Survey. The mean mass, <M{sub 200}>, is measured from weak gravitational lensing of SDSS background galaxies (Johnston et al. 2007). For 9 {le} N{sub 200} < 200, the data are well fit by a power-law, <L{sub X}>/10{sup 42} h{sup -2} ergs{sup -1} = (12.6{sub -1.3}{sup +1.4}(stat) {+-} 1.6 (sys)) (<M{sub 200}>/10{sup 14} h{sup -1} M{sub {circle_dot}}){sup 1.65{+-}0.13}. The slope agrees to within 10% with previous estimates based on X-ray selected catalogs, implying that the covariance in L{sub X} and N{sub 200} at fixed halo mass is not large. The luminosity intercept is 30%, or 2{sigma}, lower than determined from the X-ray flux-limited sample of Reiprich & Boehringer (2002), assuming hydrostatic equilibrium. This slight difference could arise from a combination of Malmquist bias and/or systematic error in hydrostatic mass estimates, both of which are expected. The intercept agrees with that derived by Stanek et al. (2006) using a model for the statistical correspondence between …
Date: May 16, 2008
Creator: Rykoff, E. S.; Evrard, A. E.; McKay, T. A.; Becker, M. R.; Johnston, D. E.; Koester, B. P. et al.
Object Type: Report
System: The UNT Digital Library
B Counting at BaBar (open access)

B Counting at BaBar

In this thesis we examine the method of counting B{bar B} events produced in the BABAR experiment. The original method was proposed in 2000, but improvements to track reconstruction and our understanding of the detector since that date make it appropriate to revisit the B Counting method. We propose a new set of cuts designed to minimize the sensitivity to time-varying backgrounds. We find the new method counts B{bar B} events with an associated systematic uncertainty of {+-} 0.6%.
Date: December 16, 2008
Creator: McGregor, Grant Duncan
Object Type: Report
System: The UNT Digital Library
Furnace Blower Electricity: National and Regional Savings Potential (open access)

Furnace Blower Electricity: National and Regional Savings Potential

Currently, total electricity consumption of furnaces is unregulated, tested at laboratory conditions using the DOE test procedure, and is reported in the GAMA directory as varying from 76 kWh/year to 1,953 kWh/year. Furnace blowers account for about 80percent of the total furnace electricity consumption and are primarily used to distribute warm air throughout the home during furnace operation as well as distribute cold air during air conditioning operation. Yet the furnace test procedure does not provide a means to calculate the electricity consumption during cooling operation or standby, which account for a large fraction of the total electricity consumption. Furthermore, blower electricity consumption is strongly affected by static pressure. Field data shows that static pressure in the house distribution ducts varies widely and that the static pressure used in the test procedure as well as the calculated fan power is not representative of actual field installations. Therefore, accurate determination of the blower electricity consumption is important to address electricity consumption of furnaces and air conditioners. This paper compares the potential regional and national energy savings of two-stage brushless permanent magnet (BPM) blower motors (the blower design option with the most potential savings that is currently available in the market) to …
Date: May 16, 2008
Creator: Center, Florida Solar Energy; Franco, Victor; Franco, Victor; Lutz, Jim; Lekov, Alex & Gu, Lixing
Object Type: Article
System: The UNT Digital Library
The Assembly of Galaxy Clusters (open access)

The Assembly of Galaxy Clusters

We study the formation of fifty-three galaxy cluster-size dark matter halos (M = 10{sup 14.0-14.76} M{sub {circle_dot}}) formed within a pair of cosmological {Lambda}CDM N-body simulations, and track the accretion histories of cluster subhalos with masses large enough to host {approx} 0.1L{sub *} galaxies. By associating subhalos with cluster galaxies, we find the majority of galaxies in clusters experience no 'pre-processing' in the group environment prior to their accretion into the cluster. On average, {approx} 70% of cluster galaxies fall into the cluster potential directly from the field, with no luminous companions in their host halos at the time of accretion; and less than {approx} 12% are accreted as members of groups with five or more galaxies. Moreover, we find that cluster galaxies are significantly less likely to have experienced a merger in the recent past ({approx}< 6 Gyr) than a field halo of the same mass. These results suggest that local, cluster processes like ram-pressure stripping, galaxy harassment, or strangulation play the dominant role in explaining the difference between cluster and field populations at a fixed stellar mass; and that pre-evolution or past merging in the group environment is of secondary importance for setting cluster galaxy properties for most …
Date: May 16, 2008
Creator: Berrier, Joel C.; Stewart, Kyle R.; Bullock, James S.; Purcell, Chris W.; Barton, Elizabeth J. & Wechsler, Risa H.
Object Type: Article
System: The UNT Digital Library
A Study of Factorization and a Measurement of CP Violation (open access)

A Study of Factorization and a Measurement of CP Violation

We report on a study of the decay {bar B}{sup 0} {yields} D*{sup +} {omega}{pi}{sup -} with the BABAR detector at the PEP-II B-factory at the Stanford Linear Accelerator Center. Based on a sample of 232 million B{sup 0}{bar B}{sup 0} decays collected between 1999 and 2004, we measure the branching fraction {Beta}({bar B}{sup 0} {yields} D*{sup +} {omega}{pi}{sup -}) = (2.88 {+-} 0.21(stat.) {+-} 0.31(syst.)) x 10{sup -3}. We study the invariant mass spectrum of the {omega}{pi}{sup -} system in this decay. This spectrum is in good agreement with expectations based on factorization and the measured spectrum in {tau}{sup -} {yields} {omega}{pi}{sup -} {nu}{sub {tau}}. We also measure the polarization of the D*{sup +} as a function of the {omega}{pi}{sup -} mass. In the mass region 1.1 to 1.9 GeV we measure the fraction of longitudinal polarization of the D*{sup +} to be {Lambda}{sub L}/{Lambda} = 0.654 {+-} 0.042(stat.) {+-} 0.016(syst.). This is in agreement with the expectations from heavy-quark effective theory and factorization assuming that the decay proceeds as {bar B}{sup 0} {yields} D*{sup +} {rho}(1450){sup -}, {rho}(1450){sup -} {yields} {omega}{pi}{sup -}. Furthermore, we present the results on the time-dependent CP asymmetry in neutral B meson decays to …
Date: January 16, 2008
Creator: Dahmes, Bryan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
ARPES study of the evolution of band structure and charge density wave properties in RTe3 ( R=Y , La, Ce, Sm, Gd, Tb, and Dy) (open access)

ARPES study of the evolution of band structure and charge density wave properties in RTe3 ( R=Y , La, Ce, Sm, Gd, Tb, and Dy)

We present a detailed angle-resolved photoemission spectroscopy (ARPES) investigation of the RTe3 family, which sets this system as an ideal"textbook" example for the formation of a nesting driven charge density wave (CDW). This family indeed exhibits the full range of phenomena that can be associated to CDWinstabilities, from the opening of large gaps on the best nested parts of Fermi surface (up to 0.4 eV), to the existence of residual metallic pockets. ARPES is the best suited technique to characterize these features, thanks to its unique ability to resolve the electronic structure in k space. An additional advantage of RTe3 is that theband structure can be very accurately described by a simple two dimensional tight-binding (TB) model, which allows one to understand and easily reproduce many characteristics of the CDW. In this paper, we first establish the main features of the electronic structure by comparing our ARPES measurements with the linear muffin-tinorbital band calculations. We use this to define the validity and limits of the TB model. We then present a complete description of the CDW properties and of their strong evolution as a function of R. Using simple models, we are able to reproduce perfectly the evolution of gaps …
Date: January 16, 2008
Creator: Hussain, Zahid; Brouet, Veronique; Yang, Wanli; Zhou, Xingjiang; Hussain, Zahid; Moore, R. G. et al.
Object Type: Article
System: The UNT Digital Library
A Simultaneous Measurement of the Branching Fractions of Ten B to Double Charm Decays (open access)

A Simultaneous Measurement of the Branching Fractions of Ten B to Double Charm Decays

This dissertation presents a simultaneous measurement of the branching fractions of ten B {yields} D{sup (*)}{bar D}{sup (*)} decays. The measurements are derived from a sample of 2.32 x 10{sup 8} B{bar B} pairs collected by the BABAR detector at the PEP-II B Factory located at Stanford Linear Accelerator Center. The branching fractions (x 10{sup -4}) are: -0.10 {+-} 0.44 {+-} 0.15 (<0.59) for B{sup 0} {yields} D{sup 0}{bar D}{sup 0}; 1.01 {+-} 1.07 {+-} 0.35 (<2.92) for B{sup 0} {yields} D*{sup 0}{bar D}{sup 0}; -1.31 {+-} 1.05 {+-} 0.41 (<0.92) for B{sup 0} {yields} D*{sup 0}{bar D}*{sup 0}; 2.81 {+-} 0.43 {+-} 0.45 for B{sup 0} {yields} D{sup +}D{sup -}; 5.72 {+-} 0.64 {+-} 0.71 for B{sup 0} {yields} D*{sup +}D{sup -}; 8.11 {+-} 0.57 {+-} 0.97 for B{sup 0} {yields} D*{sup +}D*{sup -}; 3.76 {+-} 0.57 {+-} 0.45 for B{sup -} {yields} D{sup -}D{sup 0}; 3.56 {+-} 0.52 {+-} 0.39 for B{sup -} {yields} D*{sup -}D{sup 0}; 6.30 {+-} 1.32 {+-} 0.93 for B{sup -} {yields} D{sup -}D*{sup 0}; and 8.14 {+-} 1.17 {+-} 1.11 for B{sup -} {yields} D*{sup -}D*{sup 0}. The first uncertainty is statistical while the second is systematic. The number in parentheses is the …
Date: January 16, 2008
Creator: Lae, Chung Khim
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Development Status of the ILC Marx Modulator (open access)

Development Status of the ILC Marx Modulator

The ILC Marx Modulator is under development as a lower cost alternative to the 'Baseline Conceptual Design' (BCD) klystron modulator. Construction of a prototype Marx is complete and testing is underway at SLAC. The Marx employs solid state elements, IGBTs and diodes, to control the charge, discharge and isolation of the modules. The prototype is based on a stack of sixteen modules, each initially charged to {approx}11 kV, which are arranged in a Marx topology. Initially, eleven modules combine to produce the 120 kV output pulse. The remaining modules are switched in after appropriate delays to compensate for the voltage droop that results from the discharge of the energy storage capacitors. Additional elements will further regulate the output voltage to {+-} 0.5%. The Marx presents several advantages over the conventional klystron modulator designs. It is physically smaller; there is no pulse transformer (quite massive at these parameters) and the energy storage capacitor bank is quite small, owing to the active droop compensation. It is oil-free; voltage hold-off is achieved using air insulation. It is air cooled; the secondary air-water heat exchanger is physically isolated from the electronic components. This paper outlines the current developmental status of the prototype Marx. It …
Date: June 16, 2008
Creator: Nguyen, M.; Beukers, T.; Burkhart, C.; Larsen, R.; Olsen, J. & Tang, T.
Object Type: Article
System: The UNT Digital Library
LOCALIZED CORROSION OF A537 STEEL IN SIMULATED WASTE TANK SOLUTION (open access)

LOCALIZED CORROSION OF A537 STEEL IN SIMULATED WASTE TANK SOLUTION

None
Date: October 16, 2008
Creator: Hoffman, E
Object Type: Article
System: The UNT Digital Library
Propagation or failure of detonation across an air gap in an LX-17 column: continuous time-dependent detonation or shock speed using the Embedded Fiber Optic (EFO) technique (open access)

Propagation or failure of detonation across an air gap in an LX-17 column: continuous time-dependent detonation or shock speed using the Embedded Fiber Optic (EFO) technique

The detailed history of the shock/detonation wave propagation after crossing a room-temperature-room-pressure (RTP) air gap between a 25.4 mm diameter LX-17 donor column and a 25.4 mm diameter by 25.4 mm long LX-17 acceptor pellet is investigated for three different gap widths (3.07, 2.08, and 0.00 mm) using the Embedded Fiber Optic (EFO) technique. The 2.08 mm gap propagated and the 3.07 mm gap failed and this can be seen clearly and unambiguously in the EFO data even though the 25.4 mm-long acceptor pellet would be considered quite short for a determination by more traditional means such as pins.
Date: January 16, 2008
Creator: Hare, D E; Chandler, J B; Compton, S M; Garza, R G; Grimsley, D A; Hernandez, A et al.
Object Type: Report
System: The UNT Digital Library
Pitfalls of Transparency: Lessons Learned from the Milford Flats Fire (open access)

Pitfalls of Transparency: Lessons Learned from the Milford Flats Fire

The Community Environmental Monitoring Program (CEMP) consists of a network of 29 radiation and weather monitoring stations located over a 160,000-km2 area of southern Nevada, southwestern Utah, and southeastern California. The program provides stakeholders with a hands-on role in the monitoring for airborne radioactivity that could result from ongoing or past activities on the Nevada Test Site (NTS). The CEMP’s mission includes provisions for the transparency of the monitoring data as well as public accessibility to these data. This is accomplished through direct stakeholder participation, public outreach, and near real-time uploads of monitoring data to a publicly accessible web site located at http://cemp.dri.edu/. In early July 2007, a lightning strike ignited a wildfire just outside the city of Milford in southeastern Utah. This fire, named the Milford Flats Fire, grew rapidly and eventually became the largest wildfire in recorded history in the state, burning approximately 567 square miles. At about the same time, the pressurized ion chamber (PIC) located at the CEMP station in Milford began reporting average exposure rates that ranged from four to seven times normal for the area. Initially, it was believed that elevated readings could be a result of gamma-emitting radon progeny released by the fire …
Date: January 16, 2008
Creator: Hartwell, T.; Shafer, D.; Tappen, J.; McCurdy, G.; Hurley, B. & Farmer, D.
Object Type: Article
System: The UNT Digital Library
EMSL Quarterly Highlights Report: FY 2008, 3rd Quarter (open access)

EMSL Quarterly Highlights Report: FY 2008, 3rd Quarter

The EMSL Quarterly Highlights Report covers the science, staff and user recognition, and publication activities that occurred during the 1st quarter (October 2007 - December 2007) of Fiscal Year 2008.
Date: September 16, 2008
Creator: Showalter, Mary Ann
Object Type: Report
System: The UNT Digital Library
The surface chemistry of Cu in the presence of CO2 and H2O (open access)

The surface chemistry of Cu in the presence of CO2 and H2O

The chemical nature of copper and copper oxide (Cu{sub 2}O) surfaces in the presence of CO{sub 2} and H{sub 2}O at room temperature was investigated using ambient pressure x-ray photoelectron spectroscopy. The studies reveal that in the presence of 0.1 torr CO{sub 2} several species form on the initially clean Cu, including carbonate CO{sub 3}{sup 2}, CO{sub 2}{sup {delta}-} and C{sup 0}, while no modifications occur on an oxidized surface. The addition of 0.1 ML Zn to the Cu results in the complete conversion of CO{sub 2}{sup {delta}-} to carbonate. In a mixture of 0.1 torr H{sub 2}O and 0.1 torr CO{sub 2}, new species are formed, including hydroxyl, formate and methoxy, with H{sub 2}O providing the hydrogen needed for the formation of hydrogenated species.
Date: July 16, 2008
Creator: Deng, Xingyi; Verdaguer, Albert; Herranz, Tirma; Weis, Christoph; Bluhm, Hendrik & Salmeron, Miquel
Object Type: Article
System: The UNT Digital Library
Inverse-Transition Radiation Laser Acceleration Experiments at SLAC (open access)

Inverse-Transition Radiation Laser Acceleration Experiments at SLAC

We present a series of laser-driven particle acceleration experiments that are aimed at studying laser-particle acceleration as an inverse-radiation process. To this end we employ a semi-open vacuum setup with a thin planar boundary that interacts with the laser and the electromagnetic field of the electron beam. Particle acceleration from different types of boundaries will be studied and compared to the theoretical expectations from the Inverse-radiation picture and the field path integral method. We plan to measure the particle acceleration effect from transparent, reflective, black, and rough surface boundaries. While the agreement between the two acceleration pictures is straightforward to prove analytically for the transparent and reflective boundaries the equivalence is not clear-cut for the absorbing and rough-surface boundaries. Experimental observation may provide the evidence to distinguish between the models.
Date: January 16, 2008
Creator: Colby, Eric R.; Ischebeck, R.; Mcguinness, C.; Noble, R. J.; Sears, CMS; Siemann, Robert H. et al.
Object Type: Article
System: The UNT Digital Library
SLIM, Short-pulse Technology for High Gradient Induction Accelerators (open access)

SLIM, Short-pulse Technology for High Gradient Induction Accelerators

A novel short-pulse concept (SLIM) suited to a new generation of a high gradient induction particle accelerators is described herein. It applies advanced solid state semiconductor technology and modern microfabrication techniques to a coreless induction method of charged particle acceleration first proven on a macro scale in the 1960's. Because this approach avoids use of magnetic materials there is the prospect of such an accelerator working efficiently with accelerating pulses in the nanosecond range and, potentially, at megahertz pulse rates. The principal accelerator section is envisioned as a stack of coreless induction cells, the only active element within each being a single, extremely fast (subnanosecond) solid state opening switch: a Drift Step Recovery Diode (DSRD). Each coreless induction cell incorporates an electromagnetic pulse compressor in which inductive energy developed within a transmission-line feed structure over a period of tens of nanoseconds is diverted to the acceleration of the passing charge packet for a few nanoseconds by the abrupt opening of the DSRD switch. The duration of this accelerating output pulse--typically two-to-four nanoseconds--is precisely determined by a microfabricated pulse forming line connected to the cell. Because the accelerating pulse is only nanoseconds in duration, longitudinal accelerating gradients approaching 100 MeV per …
Date: December 16, 2008
Creator: Arntz, Floyd; Kardo-Sysoev, A. & Krasnykh, A.
Object Type: Article
System: The UNT Digital Library
X-ray stereo microscopy for investigation of dynamics in soils (open access)

X-ray stereo microscopy for investigation of dynamics in soils

The presented combination of stereo imaging and elemental mapping with soft X-ray microscopy reveals the spatial arrangement of naturally aqueous colloidal systems, e.g. iron oxides in soil colloid clusters. Changes in the spatial arrangement can be induced by manipulating the sample mounted to the X-ray microscope and thus be investigated directly.
Date: September 16, 2008
Creator: Gleber, S.-C.; Sedlmair, J.; Bertilson, M.; von Hofsten, O.; Heim, S.; Guttmann, P. et al.
Object Type: Article
System: The UNT Digital Library
Remaining Sites Verification Package for the 100-B-21:2 Subsite (100-B/C Discovery Pipeline DS-100BC-002), Waste Site Reclassification Form 2008-003 (open access)

Remaining Sites Verification Package for the 100-B-21:2 Subsite (100-B/C Discovery Pipeline DS-100BC-002), Waste Site Reclassification Form 2008-003

The 100-B-21:2 waste site consists of the immediate area of the DS-100BC-02 pipeline. In accordance with this evaluation, the confirmatory and verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: June 16, 2008
Creator: Capron, J. M.
Object Type: Report
System: The UNT Digital Library
Remaining Sites Verification Package for the 331 Life Sciences Laboratory Drain Field Septic System, Waste Site Reclassification Form 2008-020 (open access)

Remaining Sites Verification Package for the 331 Life Sciences Laboratory Drain Field Septic System, Waste Site Reclassification Form 2008-020

The 331 Life Sciences Laboratory Drain Field (LSLDF) septic system waste site consists of a diversion chamber, two septic tanks, a distribution box, and a drain field. This septic system was designed to receive sanitary waste water, from animal studies conducted in the 331-A and 331-B Buildings, for discharge into the soil column. However, field observations and testing suggest the 331 LSLDF septic system did not receive any discharges. In accordance with this evaluation, the confirmatory sampling results support a reclassification of the 331 LSLDF waste site to No Action. This site does not have a deep zone or other condition that would warrant an institutional control in accordance with the 300-FF-2 ROD under the industrial land use scenario.
Date: October 16, 2008
Creator: Capron, J. M.
Object Type: Report
System: The UNT Digital Library
Measurement of the Branching Fractions of the Rare Decays B0 to Ds(*)+pi-,B0 to Ds(*)+rho-, and B0 to Ds(*)-K(*)+ (open access)

Measurement of the Branching Fractions of the Rare Decays B0 to Ds(*)+pi-,B0 to Ds(*)+rho-, and B0 to Ds(*)-K(*)+

The authors report the measurement of the branching fractions of the rare decays B{sup 0} {yields} D{sub s}{sup (*)+} {pi}{sup -}, B{sup 0} {yields} D{sub s}{sup (*)+} {rho}{sup -}, and B{sup 0} {yields} D{sub s}{sup (*)-} K{sup (*)+} in a sample of 381 x 10{sup 6} {Upsilon}(4S) decays into B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They present evidence for the decay B{sup 0} {yields} D{sub s}{sup -} K*{sup +} and the vector-vector decays B{sup 0} {yields} D{sub s}{sup *+} {rho}{sup -} and B{sup 0} {yields} D{sub s}{sup *-} K{sup *+}, as well as the first measurement of the vector meson polarization in these decays. They also determine the ratios of the CM-suppressed to CKM-favored amplitudes r(D{sup (*)}{pi}) and r(D{sup (*)}{rho}) in decays B{sup 0} {yields} D{sup (*)}{sup {+-}}{pi}{sup {-+}} and B{sup 0} {yields} D{sup (*)}{sup {+-}}{rho}{sup {-+}}, and comment on the prospects for measuring the Cp observable sin(2{beta} + {gamma}).
Date: April 16, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Binary Pseudo-random Grating Standard for Calibration of Surface Profilometers (open access)

Binary Pseudo-random Grating Standard for Calibration of Surface Profilometers

We suggest and describe the use of a binary pseudo-random (BPR) grating as a standard test surface for measurement of the modulation transfer function (MTF) of interferometric microscopes. Knowledge of the MTF of a microscope is absolutely necessary to convert the measured height distribution of a surface undergoing metrology into an accurate power spectral density (PSD) distribution. For an'ideal' microscope with an MTF function independent of spatial frequency out to the Nyquist frequency of the detector array with zero response at higher spatial frequencies, a BPR grating would produce a flat 1D PSD spectrum, independent of spatial frequency. For a'real' instrument, the MTF is found as the square root of the ratio of the PSD spectrum measured with the BPR grating to the'ideal,' spatial frequency independent, PSD spectrum. We present the results from a measurement of the MTF of MicromapTM-570 interferometric microscope demonstrating a high efficiency for the calibration method.
Date: January 16, 2008
Creator: Yashchuk, Valeriy; Yashchuk, Valeriy V.; McKinney, Wayne R. & Takacs, Peter Z.
Object Type: Article
System: The UNT Digital Library
Seismic Data for Evaluation of Ground Motion Hazards in Las Vegas in Support of Test Site Readiness Ground Motion (open access)

Seismic Data for Evaluation of Ground Motion Hazards in Las Vegas in Support of Test Site Readiness Ground Motion

In this report we describe the data sets used to evaluate ground motion hazards in Las Vegas from nuclear tests at the Nevada Test Site. This analysis is presented in Rodgers et al. (2005, 2006) and includes 13 nuclear explosions recorded at the John Blume and Associates network, the Little Skull Mountain earthquake and a temporary deployment of broadband station in Las Vegas. The data are available in SAC format on CD-ROM as an appendix to this report.
Date: January 16, 2008
Creator: Rodgers, A
Object Type: Report
System: The UNT Digital Library
Search for New Physics Beyond the Standard Model at BaBar (open access)

Search for New Physics Beyond the Standard Model at BaBar

A review of selected recent BaBar results are presented that illustrate the ability of the experiment to search for physics beyond the standard model. The decays B {yields} {tau}{nu} and B {yields} s{gamma} provide constraints on the mass of a charged Higgs. Searches for Lepton Flavour Violation could provide a clear signal for beyond the standard model physics. Babar does not observe any signal for New Physics with the current dataset.
Date: April 16, 2008
Creator: Barrett, Matthew & U., /Brunel
Object Type: Article
System: The UNT Digital Library