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Adaptive optics high resolution spectroscopy: present status and future direction (open access)

Adaptive optics high resolution spectroscopy: present status and future direction

High resolution spectroscopy experiments with visible adaptive optics (AO) telescopes at Starfire Optical Range and Mt. Wilson have demonstrated that spectral resolution can be routinely improved by a factor of - 10 over the seeing-limited case with no extra light losses at visible wavelengths. With large CCDs now available, a very wide wavelength range can be covered in a single exposure. In the near future, most large ground-based telescopes will be equipped with powerful A0 systems. Most of these systems are aimed primarily at diffraction-limited operation in the near IR. An exciting new opportunity will thus open up for high resolution IR spectroscopy. Immersion echelle gratings with much coarser grooves being developed by us at LLNL will play a critical role in achieving high spectral resolution with a compact and low cost IR cryogenically cooled spectrograph and simultaneous large wavelength coverage on relatively small IR detectors. We have constructed a new A0 optimized spectrograph at Steward Observatory to provide R = 200,000 in the optical, which is being commissioned at the Starfire Optical Range 3.5m telescope. We have completed the optical design of the LLNL IR Immersion Spectrograph (LISPEC) to take advantage of improved silicon etching technology. Key words: adaptive …
Date: July 27, 1999
Creator: Alcock, C.; Angel, R.; Ciarlo, D.; Fugate, R. O.; Ge, J.; Kuzmenko, P. et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 100, No. 110, Ed. 1 Tuesday, July 27, 1999 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 110, Ed. 1 Tuesday, July 27, 1999

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 27, 1999
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Appropriations for FY2000: Interior and Related Agencies (open access)

Appropriations for FY2000: Interior and Related Agencies

This report is a guide to the Interior and Related Agencies Appropriations bill, which includes funding for agencies and programs in four separate federal departments as well as smaller agencies and diverse programs.
Date: July 27, 1999
Creator: Greenwood, Alfred R.
Object Type: Report
System: The UNT Digital Library
B {0 over d} mixing and CP violation measurements at the Tevatron (open access)

B {0 over d} mixing and CP violation measurements at the Tevatron

We present six time-dependent B<sup>0</sup><sub>d</sub> mixing measurements of {Delta}m<sub>d</sub> from the CDF Run I data. The CDF average is {Delta}m<sub>d</sub> = .494<sup>&plusmn;.026</sup><sub>&plusmn;.026</sub>(ps)<sup>-1</sup>. We also present a measurement of the CP-violating asymmetry sin(2{beta}) using a sample of B<sup>0</sup>/{anti B}<sup>0</sup> {yields} J/{psi} K<sup>0</sup><sub>s</sub> decays and report sin(2{beta}) = .79 <sup>+41</sup><sub>-.44</sub>.
Date: July 27, 1999
Creator: Byrum, K.
Object Type: Article
System: The UNT Digital Library
Battlefield Automation: Performance Uncertainties Are Likely When Army Fields Its First Digitized Division (open access)

Battlefield Automation: Performance Uncertainties Are Likely When Army Fields Its First Digitized Division

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Army's progress toward its goal of fielding a digitized division by the end of 2000, focusing on: (1) the high-priority systems needed to accomplish the digitization fielding goal; (2) the acquisition status of these high-priority systems; and (3) any performance uncertainties that could confront the Army after its first digitized division is fielded."
Date: July 27, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 77, No. 231, Ed. 1 Tuesday, July 27, 1999 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 77, No. 231, Ed. 1 Tuesday, July 27, 1999

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 27, 1999
Creator: Dobbs, Gary
Object Type: Newspaper
System: The Portal to Texas History
Bexar County Long Range Financial Forecast: FY 1999-2000 through FY 2003-2004 (open access)

Bexar County Long Range Financial Forecast: FY 1999-2000 through FY 2003-2004

Long range financial forecast provides information to help decision-makers plan for the future financial needs of Bexar County; takes current expenditure levels, known cost increases, one-time expenses and inflation, and forecasts the effects of these factors on the County's financial condition for fiscal years 1999 through 2003.
Date: July 27, 1999
Creator: Bexar County (Tex.). Commissioners Court.
Object Type: Book
System: The Portal to Texas History
Biographical Sketch - Terri Hodge (open access)

Biographical Sketch - Terri Hodge

A biographical sketch of Terri Hodge describing Hodge's life and accomplishments.
Date: July 27, 1999
Creator: unknown
Object Type: Letter
System: The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 94, No. 60, Ed. 1 Tuesday, July 27, 1999 (open access)

The Boerne Star (Boerne, Tex.), Vol. 94, No. 60, Ed. 1 Tuesday, July 27, 1999

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: July 27, 1999
Creator: Keasling, Edna & Fierro, Jennifer
Object Type: Newspaper
System: The Portal to Texas History
Budget FY2000: A Chronology with Internet Access (open access)

Budget FY2000: A Chronology with Internet Access

This report provides a select chronology of congressional and presidential actions and documents related to major budget events in calendar year 1999, covering the FY2000 budget. While the paper copy provides numerous Internet addresses, congressional offices can also use the Internet version of this report to access active links to appropriations and budget legislation, budget and economic data tables, pie charts, glossaries, selected testimony, publications, the President’s budget documents, and CRS products.
Date: July 27, 1999
Creator: Watkins, Susan E.
Object Type: Report
System: The UNT Digital Library
CAMAC Driver Support for Windows NT{trademark} and Lunux{trademark} (open access)

CAMAC Driver Support for Windows NT{trademark} and Lunux{trademark}

CAMAC is a Modular Instrumentation and Digital Interface System defined as a standardized instrumentation system for Computer Automated Measurement and Control. CAMAC hardware and software has been defined by the NIM Committee (National Instrumentation Methods Committee) of the US Department of Energy and the ESONE Committee (European Standards on Nuclear Electronics Committee) of European Laboratories. Fermi National Accelerator Laboratory has for many years produced software packages that follow the ANSI/IEEE standard 758-1979 for a variety of computers, CAMAC controller interfaces, and operating systems. In order to enable the re-use of existing hardware and software, Fermilab now supports standard routine libraries and drivers for Windows NT 4.0 and the Linux operating systems for the Jorway 411s SCSI Bus CAMAC Driver[l] and the Jorway73A SCSI Bus CAMAC Crate Controller. A number of test stands and small experiments both on-site and off-site are using this software for their CAMAC data acquisition needs.
Date: July 27, 1999
Creator: Streets, D.A. Slimmer and J.M.
Object Type: Article
System: The UNT Digital Library
Campaign Finance: Contributions From Gambling Interests Have Increased (open access)

Campaign Finance: Contributions From Gambling Interests Have Increased

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO determined for the 1992, 1994, 1996, and 1998 elections the total amount of contributions from gambling interests to: (1) federal candidates, including the total number of federal candidates that accepted those contributions; and (2) national political party committees, as well as separate totals for the Republican National Committee (RNC), the National Republican Congressional Committee (NRCC), the Democratic National Committee (DNC), and the Democratic Congressional Campaign Committee (DCCC)."
Date: July 27, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Combined SLD Measurement of Ab at the Z0 Resonance using Various Techniques (open access)

Combined SLD Measurement of Ab at the Z0 Resonance using Various Techniques

We present a new preliminary combination of measurements of the parity-violation parameter A<sub>b</sub> made by the SLD collaboration using various experimental techniques. The techniques differ in detail, but in general a sample of b anti-b events is selected or enhanced by using the topologically reconstructed mass of the separated vertices formed by decaying B hadrons. The direction of the b(anti-b) quark is signed by one of four final state tags: jet charge, vertex charge, leptons, or identified K<sup>=</sup> from the b vertex. We account for statistical and systematic correlations between the four analyses to arrive at our combined result: A<sub>b</sub> = 0.905 ± 0.017(stat) ± 0.020(syst).
Date: July 27, 1999
Creator: Crawford, Glen D
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, July 27, 1999 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, July 27, 1999

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 27, 1999
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Federal Budget: The President's Midsession Review (open access)

Federal Budget: The President's Midsession Review

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed the President's Midsession Review and the implications of the President's proposals on fiscal policy and the federal budget."
Date: July 27, 1999
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Final Report: Nitrogen Control of Chloroplast Differentiation and Metabolism, March 31, 1996 - March 31, 1999 (open access)

Final Report: Nitrogen Control of Chloroplast Differentiation and Metabolism, March 31, 1996 - March 31, 1999

None
Date: July 27, 1999
Creator: Schmidt, G.W. & Bruns, B.U.
Object Type: Report
System: The UNT Digital Library
Final Report: Role of Physics Students in APS Centennial Meeting, December 15, 1998 - December 14, 1999 (open access)

Final Report: Role of Physics Students in APS Centennial Meeting, December 15, 1998 - December 14, 1999

None
Date: July 27, 1999
Creator: Franz, Judy R.
Object Type: Report
System: The UNT Digital Library
GIS Meets Airborne MSS: Geospatial Applications of High-Resolution Multispectral Data (open access)

GIS Meets Airborne MSS: Geospatial Applications of High-Resolution Multispectral Data

Bechtel Nevada operates and flies Daedalus multispectral scanners for funded project tasks at the Department of Energy's Remote Sensing Laboratory. Historically, processing and analysis of multispectral data has afforded scientists the opportunity to see natural phenomena not visible to the naked eye. However, only recently has a system, more specifically a Geometric Correction System, existed to automatically geo-reference these data directly into a Geographic Information (GIS) database. Now, analyses, performed previously in a nongeospatial environment, are integrated directly into an Arc/Info GIS. This technology is of direct benefit to environmental and emergency response applications.
Date: July 27, 1999
Creator: Guber, Albert
Object Type: Article
System: The UNT Digital Library
The Harper Herald (Harper, Tex.), Vol. 69, No. 126, Ed. 1 Tuesday, July 27, 1999 (open access)

The Harper Herald (Harper, Tex.), Vol. 69, No. 126, Ed. 1 Tuesday, July 27, 1999

Weekly newspaper from Harper, Texas that includes local, state, and national news along with advertising.
Date: July 27, 1999
Creator: Bishop, Karen
Object Type: Newspaper
System: The Portal to Texas History
Highly-Efficient Laser with Self-Aligned Waveguide and Current Confinement by Selective Oxidation (open access)

Highly-Efficient Laser with Self-Aligned Waveguide and Current Confinement by Selective Oxidation

We report highly efficient, low-threshold-current edge-emitting lasers where both the optical waveguide and lateral current confinement are achieved by lateral selective oxidation of AlGaAs. External differential quantum efficiency in excess of 95% and 40% wall-plug efficiency are demonstrated in 600 {micro}m-long devices without facet coatings. Shorter, 300-{micro}m-long, uncoated devices have &lt;6 mA threshold currents. This high-performance is a combined result of placement of the oxide layers so as to achieve the minimum optical mode volume and bi-parabolic grading of the Al{sub x}Ga{sub 1{minus}x}As heteroepitaxy for minimum height/potential barriers, less than 15 meV, created by the wide-energy-gap layers required for selective wet oxidation. Since the initial development of wet AlGaAs oxidation methods, a number of oxidized edge-emitting laser concepts have been tried. The most successful of these have used lateral selective oxidation of AlGaAs layers between 100 and 300 nm thickness. These layers have been used as current restricting apertures or for both current restriction and lateral waveguiding. Use of an oxide layer above and below the laser active region offers the ability to create a self-aligned waveguide with current apertures on both sides of the pn-junction in a process requiring only one epitaxial growth step. Previous use apertures for these …
Date: July 27, 1999
Creator: Allerman, A.; Blum, O.; Gao, Y. & Vawter, G. A.
Object Type: Article
System: The UNT Digital Library
Improving Regional Seismic Event Location Through Calibration of the International Monitoring System (open access)

Improving Regional Seismic Event Location Through Calibration of the International Monitoring System

At Lawrence Livermore National Laboratory (LLNL), we are working to help calibrate the 170 seismic stations that are part of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring network, in order to enhance the network's ability to locate small seismic events. These low magnitude events are likely to be recorded by only the closest of seismic stations, ranging from local to near teleseismic distances. At these distance ranges, calibration statistics become highly nonstationary, challenging us to develop more general statistical models for proper calibration. To meet the goals outlined above, we are developing a general nonstationary framework to accurately calibrate seismic travel-time predictions over the full distance range, from local, to regional, to teleseismic distances. The objective of this framework is to develop valid region-specific corrections for the Middle Fast, North Africa, and portions of the Soviet Union, to assess our progress towards meeting calibration goals, and to perform cost-benefit analysis for future calibrations. The framework integrates six core components essential to accurate calibration. First, is the compilation and statistical characterization of well located reference events, including aftershock sequences, mining explosions and rockbursts, calibration explosions, and teleseismically constrained events (Harris et al., SSA 1999; Hanley et al., SSA 1999). Second, is the …
Date: July 27, 1999
Creator: Schultz, Craig A.; Myers, Stephen C.; Flanagan, Megan; Swenson, Jennifer; Hanley, William & Pasyanos, Micheal
Object Type: Article
System: The UNT Digital Library
Measurement of the B{sup +} and B{sup 0} Lifetimes using Topological Vertexing at SLD (open access)

Measurement of the B{sup +} and B{sup 0} Lifetimes using Topological Vertexing at SLD

The lifetimes of B{sup +} and B{sup 0} mesons have been measured using the entire sample of 550,000 hadronic Z{sup 0} decays collected by the SLD experiment at the SLC between 1993 and 1998. In this paper, we describe the inclusive analysis of the 350,000 hadronic Z{sup 0} decays collected in 1997-98 with the upgraded SLD vertex detector. In this data period, a high statistics sample of 30903 (20731) charged (neutral) vertices with good charge purity is obtained. The charge purity is enhanced by using the vertex mass, the SLC electron beam polarization (73% for 1997-8) and an opposite hemisphere jet charge technique. Combining the results of this data sample with the results from the earlier data yield the following preliminary values: {tau}{sub B{sup +}} = 1.623 {+-} 0.020(stat) {+-} 0.034(syst) ps, {tau}{sub B{sup +}} = 1.565 {+-} 0.021(stat) {+-} 0.043(syst) ps, {tau}{sub B{sup +}} = {tau}{sub B{sup 0}} = 1.037 {+-} {sub 0.024}{sup 0.025}(stat) {+-} 0.024(syst).
Date: July 27, 1999
Creator: Baird, Kenneth
Object Type: Report
System: The UNT Digital Library
Model Calculations of Continuous-Wave Laser Ionization of Krypton (open access)

Model Calculations of Continuous-Wave Laser Ionization of Krypton

This report describes modeling of a scheme that uses continuous-wave (CW) lasers to ionize selected isotopes of krypton with high isotopic selectivity. The models predict that combining this ionization scheme with mass spectrometric measurement of the resulting ions can be the basis for ultra-sensitive methods to measure {sup 85}Kr in the presence of a 10{sup 11} excess of the stable krypton isotopes. Two experimental setups are considered in this model: the first setup is for krypton as a static gas, the second is for krypton in an atomic beam. In the static gas experiment, for a total krypton press of 10{sup {minus}4} torr and 10 W of power in the cavity, the model predicts a total krypton ion current of 4.6 x 10{sup 8} s{sup {minus}1} and for a {sup 85}Kr/Kr of 10{sup {minus}11} a {sup 85}Kr ion current of 3.5 s{sup {minus}1} or about 10,000 per hour. The atomic beam setup allowed higher isotopic selectivity; the model predicts a {sup 85}Kr ion current of 18 s{sup {minus}1} or 65,000 per hour.
Date: July 27, 1999
Creator: Cannon, Bret D.
Object Type: Report
System: The UNT Digital Library
Nuclear material estimation and uncertainties for the spent fuel treatment at FCF. (open access)

Nuclear material estimation and uncertainties for the spent fuel treatment at FCF.

Spent fuel from the Experimental Breeder Reactor-II (EBR-II) is treated at the Fuel Conditioning Facility (FCF) located at Argonne National Laboratory-West (ANL-W). A number of sensitive nuclear material streams are present in the facility, which mainly include material in the input spent fuel, the element chopper, the electrorefiner, the cathode processor, and the casting furnace. Different types of measurements and calculations are performed in order to estimate the amount of material in those streams. There are three basic types of measurements: weight, elemental and isotopic fractions, and liquid level measurements. Materials in some streams are determined using validated models, which include the mass and composition of the input spent fuel. This paper describes the different streams of sensitive nuclear material for the facility, and the methods for their measurements or estimation as part of the MC&amp;A system at FCF. It also describes the analytical and sampling uncertainties associated with those measurements and estimates, which are required for the facility variance propagation calculations.
Date: July 27, 1999
Creator: Battisti, T.; Bucher, R. G.; Krsul, J.; Mariani, R. D.; McKnight, R. D.; Vaden, D. et al.
Object Type: Article
System: The UNT Digital Library