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2D Spatial Gain Profiles in Multiple-Pulse Driven Ne-like Ge Lasers (open access)

2D Spatial Gain Profiles in Multiple-Pulse Driven Ne-like Ge Lasers

In this paper, we present the direct spatial measurement of the two-dimensional gain profiles for the Ne-like Ge 196 Å laser line using a slab target illuminated by the multiple pulse technique. To understand the spatial dependence for Ge plasmas driven by a series of 100 ps pulses 400 ps apart we did a series of Nova experiments backlighting short Ge amplifiers. Two-dimensional, high-resolution, spatial images of the 196 Å laser emission from the output aperture of the amplifiers were measured to determine the spatial position of the gain. The amplifier lengths were chosen to be short enough to avoid the significant refraction effects which have dominated the analysis of previous near field imaging experiments. To assure good temporal overlap, the traveling wave geometry was used to illuminate both the amplifier and backlighter. The amplifier design included a wire fiducial that provided an absolute spatial reference and avoided the usual difficulty of determining the location of the target surface. We compare the measured spatial gain profiles with simulations done using LASNEX, which calculates the hydrodynamic evolution of the plasma, and XRASER, which uses the temperatures and densities from LASNEX to do the gain and kinetics calculations.
Date: September 21, 1998
Creator: Dunn, J.; Li, Y.; Nilsen, J. & Osterheld, A. L.
Object Type: Article
System: The UNT Digital Library
Advanced Thermal Barrier Coating System Development. Technical progress report (open access)

Advanced Thermal Barrier Coating System Development. Technical progress report

The objectives of the program are to provide an improved TBC system with increased temperature capability and improved reliability relative to current state of the art TBC systems. The development of such a coating system is essential to the ATS engine meeting its objectives. The base program consists of three phases: Phase I: Program Planning - Complete; Phase II: Development; and Phase III: Selected Specimen - Bench Test. Work is being performed in Phase II and III of the program.
Date: September 21, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 99, No. 162, Ed. 1 Monday, September 21, 1998 (open access)

Altus Times (Altus, Okla.), Vol. 99, No. 162, Ed. 1 Monday, September 21, 1998

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: September 21, 1998
Creator: Cole, Carol
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 108, No. 14, Ed. 1 Monday, September 21, 1998 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 108, No. 14, Ed. 1 Monday, September 21, 1998

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: September 21, 1998
Creator: Schwind, Jim & Looby, Edward
Object Type: Newspaper
System: The Portal to Texas History
[Arts Assessment Instrument Review - Email Correspondence by Donald J. Killeen to NSC Members and RIG Directors] (open access)

[Arts Assessment Instrument Review - Email Correspondence by Donald J. Killeen to NSC Members and RIG Directors]

A documented email conversation from Donald J. Killeen to the National Steering Committee (NSC) members and Regional Institute Group (RIG) directors unfolds a strategic dialogue on the review of arts assessment instruments.
Date: September 21, 1998, 2:14 p.m.
Creator: unknown
Object Type: Letter
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 76, No. 278, Ed. 1 Monday, September 21, 1998 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 76, No. 278, Ed. 1 Monday, September 21, 1998

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: September 21, 1998
Creator: Dobbs, Gary
Object Type: Newspaper
System: The Portal to Texas History
Catalytic partial oxidation reforming of hydrocarbon fuels. (open access)

Catalytic partial oxidation reforming of hydrocarbon fuels.

The polymer electrolyte fuel cell (PEFC) is the primary candidate as the power source for light-duty transportation systems. On-board conversion of fuels (reforming) to supply the required hydrogen has the potential to provide the driving range that is typical of today's automobiles. Petroleum-derived fuels, gasoline or some distillate similar to it, are attractive because of their existing production, distribution, and retailing infrastructure. The fuel may be either petroleum-derived or other alternative fuels such as methanol, ethanol, natural gas, etc. [1]. The ability to use a variety of fuels is also attractive for stationary distributed power generation [2], such as in buildings, or for portable power in remote locations. Argonne National Laboratory has developed a catalytic reactor based on partial oxidation reforming that is suitable for use in light-duty vehicles powered by fuel cells. The reactor has shown the ability to convert a wide variety of fuels to a hydrogen-rich gas at less than 800 C, temperatures that are several hundreds of degrees lower than alternative noncatalytic processes. The fuel may be methanol, ethanol, natural gas, or petroleum-derived fuels that are blends of various hydrocarbons such as paraffins, olefins, aromatics, etc., as in gasoline. This paper will discuss the results obtained …
Date: September 21, 1998
Creator: Ahmed, S.
Object Type: Article
System: The UNT Digital Library
Chickasha Daily Express (Chickasha, Okla.), Ed. 1 Monday, September 21, 1998 (open access)

Chickasha Daily Express (Chickasha, Okla.), Ed. 1 Monday, September 21, 1998

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: September 21, 1998
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
[A Dialogue on Arts Assessment Instruments - Insights from Donald J. Killeen to NSC Members and RIG Directors] (open access)

[A Dialogue on Arts Assessment Instruments - Insights from Donald J. Killeen to NSC Members and RIG Directors]

A nuanced email exchange with the National Steering Committee (NSC) members and Regional Institute Group (RIG) directors. This documented conversation delves deep into the collective exploration of arts assessment instruments, unveiling considerations, perspectives, and collaborative endeavors.
Date: September 21, 1998, 2:27 p.m.
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Funeral Program for Morris Daugherty, II, September 21, 1998] (open access)

[Funeral Program for Morris Daugherty, II, September 21, 1998]

Funeral program for Morris Daugherty II, born February 19, 1955 and died September 12, 1998. The funeral was held September 21, 1998 at Ernest T. Dixon United Methodist Church, officiated by Dr. Prenza L. Woods. The funeral arrangements were made through Lewis Funeral Home and he was buried in Fort Sam Houston National Cemetery near San Antonio, Texas.
Date: September 21, 1998
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Improved temperature regulation of APS linac RF components. (open access)

Improved temperature regulation of APS linac RF components.

The temperature of the APS S-Band linac's high-power rf components is regulated by water from individual closed-loop deionized (DI) water systems. The rf components are all made of oxygen-free high-conductivity copper and respond quickly to temperature changes. The SLED cavities are especially temperature-sensitive and cause beam energy instabilities when the temperature is not well regulated. Temperature regulation better than {+-} 0.1 F is required to achieve good energy stability. Improvements in the closed-loop water systems have enabled them to achieve a regulation of {+-} 0.05 F over long periods. Regulation philosophy and equipment are discussed and numerical results are presented.
Date: September 21, 1998
Creator: Dortwegt, R.
Object Type: Article
System: The UNT Digital Library
International Labor Organization: A Fact Sheet (open access)

International Labor Organization: A Fact Sheet

None
Date: September 21, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Measuring the wavelengths of the Ni-like 4d <sup>1</sup>S<sub>0</sub> (arrow) 4p <sup>1</sup>P<sub>1</sub> and 4f <sup>1</sup>P<sub>1</sub> (arrow) 4d <sup>1</sup>P<sub>1</sub> x-ray laser lin (open access)

Measuring the wavelengths of the Ni-like 4d <sup>1</sup>S<sub>0</sub> (arrow) 4p <sup>1</sup>P<sub>1</sub> and 4f <sup>1</sup>P<sub>1</sub> (arrow) 4d <sup>1</sup>P<sub>1</sub> x-ray laser lin

In this work we present measurements of the wavelengths of the nickel-like 3d9 4d IS0 + 3d94p � P, X-ray laser line in several low-Z nickel-like ions ranging from yttrium (Z=39) to cadmium (Z=45). With the help of these laser results, we identify this line to very high accuracy in nonlasing plasmas from gallium (Z=3 1) to molybdenum (Z=42). The measured wavelengths are compared with optimized level calculations using the multi-configuration Dirac-Fock code of Grant et al. As an example, for yttrium, we calculate a wavelength of 240.2 A, and measure wavelengths of 240.1 I i 0.30 A in the lasing plasma and 240.135 + 0.015 A in the nonlasing plasma. Accurate values of these wavelengths are essential for performing plasma imaging and interferometry experiments with multilayer optics which use the X-ray laser to backlight other plasmas. These results also provide important atomic data which is currently missing about the energy of the Id � S, level in the Ni I sequence and help guide evperimentalists who are looking for lasing in these materials for the first time. We also observe lasing on the nickel-like 3d9 4f � P, + 3d94d � P, X-ray laser line in Zr, Nb, and …
Date: September 21, 1998
Creator: Churilov, S; Nilsen, J & Ryobtsev, A
Object Type: Article
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 28, Ed. 1 Monday, September 21, 1998 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 28, Ed. 1 Monday, September 21, 1998

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: September 21, 1998
Creator: Allam, Heather
Object Type: Newspaper
System: The Gateway to Oklahoma History
Perry Daily Journal (Perry, Okla.), Vol. 105, No. 184, Ed. 1 Monday, September 21, 1998 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 105, No. 184, Ed. 1 Monday, September 21, 1998

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: September 21, 1998
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Poisson alignment reference system implementation at the Advanced Photon Source. (open access)

The Poisson alignment reference system implementation at the Advanced Photon Source.

The Poisson spot was established using a collimated laser beam from a 3-mW diode laser. It was monitored on a quadrant detector and found to be very sensitive to vibration and air disturbances. Therefore, for future work we strongly recommend a sealed vacuum tube in which the Poisson line may be propagated. A digital single-axis feedback system was employed to generate an straight line reference (SLR) on the X axis. Pointing accuracy was better than 8 {+-} 2 microns at a distance of 5 m. The digital system was found to be quite slow with a maximum bandwidth of 47 {+-} 9 Hz. Slow drifts were easily corrected but any vibration over 5 Hz was not. We recommend an analog proportional-integral-derivative (PID) controller for high bandwidth and smooth operation of the kinematic mirror. Although the Poisson alignment system (PAS) at the Advanced Photon Source is still in its infancy, it already shows great promise as a possible alignment system for the low-energy undulator test line (LEUTL). Since components such as wigglers and quadruples will initially be aligned with respect to each other using conventional means and mounted on some kind of rigid rail, the goal would be to align six …
Date: September 21, 1998
Creator: Feier, I.
Object Type: Article
System: The UNT Digital Library
Progress in understanding the short-pulse-driven collisional x-ray lasers (open access)

Progress in understanding the short-pulse-driven collisional x-ray lasers

Recently, the technique of using a nsec pulse to preform and ionize the plasma followed by a psec pulse to heat the plasma has enabled low-Z neon-like and nickel-like ions to lase driven by small lasers with only ten joules of energy. In this work we model recent experiments done using the COMET laser at LLNL to illuminate I cm long slab targets of Ti with a 4.8 J, 800 ps prepulse followed 1.6 nsec later by a 6 J, 1 psec drive pulse. The LASNEX code is used to calculate the hydrodynamic evolution of the plasma and provide the temperatures and densities fo the XRASER code, which then does the kinetics calculations to determine the gain. The temporal and spatial evolution of the plasma is studied both with and without radiation transport included for the 3d and 3s (arrow) 2p Ne-like Ti resonance lines. Large regions with gains greater than 80 cm<sub>minus1</sub> are predicted for the 3p <sup>1</sup>S<sub>0</sub> (arrow), 3s <sup>1</sup>P,<sub>1</sub>Ne-like Ti laser line at 326 Å. Given the large gain and low gradients in these plasmas, we do propagation calculations including refraction to understand which regions have the right combination of high gain and low gradients to contribute …
Date: September 21, 1998
Creator: Nilsen, J.
Object Type: Article
System: The UNT Digital Library
Quality assurance program plan fuel supply shutdown (open access)

Quality assurance program plan fuel supply shutdown

This Quality Assurance Program plan (QAPP) describes how the Fuel Supply Shutdown (FSS) project organization implements the quality assurance requirements of HNF-MP-599, Project Hanford Quality Assurance Program Description (QAPD) and the B and W Hanford Company Quality Assurance Program Plan (QAPP), FSP-MP-004. The QAPP applies to facility structures, systems, and components and to activities (e.g., design, procurement, testing, operations, maintenance, etc.) that could affect structures, systems, and components. This QAPP also provides a roadmap of applicable Project Hanford Policies and Procedures (PHPP) which may be utilized by the FSS project organization to implement the requirements of this QAPP.
Date: September 21, 1998
Creator: Metcalf, I. L.
Object Type: Report
System: The UNT Digital Library
A Raman Fiber Optic Probe Assembly for use in Hostile Environments (open access)

A Raman Fiber Optic Probe Assembly for use in Hostile Environments

This invention provides a device for Raman spectroscopic measurement of composition and concentrations in a hostile environment by the use of a first fiber optic as a means of directing high intensity monochromatic light from a laser to the hostile environment and a second fiber optic to receive the lower intensity scattered light for transmittal to a monochromator for analysis. To avoid damage to the fiber optics, they are protected from the hostile environment. A preferred embodiment of the Raman fiber optic probe is able to obtain Raman spectra of corrosive gases and solutions at temperatures to 600 F and pressures up to 2000 psi. The incident exciting fiber optic cable makes an angle of substantially 90{degree} with the collecting fiber optic cable. This 90{degree} geometry minimizes the Rayleigh scattering signal picked up by the collecting fiber, because the intensity of Rayleigh scattering is lowest in the direction perpendicular to the beam path of the exciting light and therefore a 90{degree} scattering geometry optimizes the signal to noise ratio.
Date: September 21, 1998
Creator: Schmucker, John E.; Falk, Jon C.; Archer, William B. & Blasi, Raymond J.
Object Type: Patent
System: The UNT Digital Library
Report on Intact and Degraded Criticality for Selected Plutonium Waste Forms in a Geologic Repository, Volume I: MOX SNF (open access)

Report on Intact and Degraded Criticality for Selected Plutonium Waste Forms in a Geologic Repository, Volume I: MOX SNF

As part of the plutonium waste form development and down-select process, repository analyses have been conducted to evaluate the long-term performance of these forms for repository acceptance. Intact and degraded mode criticality analysis of the mixed oxide (MOX) spent fuel is presented in Volume I, while Volume II presents the evaluations of the waste form containing plutonium immobilized in a ceramic matrix. Although the ceramic immobilization development program is ongoing, and refinements are still being developed and evaluated, this analysis provides value through quick feed-back to this development process, and as preparation for the analysis that will be conducted starting in fiscal year (FY) 1999 in support of the License Application. While no MOX fuel has been generated in the United States using weapons-usable plutonium, Oak Ridge National Laboratory (ORNL) has conducted calculations on Westinghouse-type reactors to determine the expected characteristics of such a fuel. These spent nuclear fuel (SNF) characteristics have been used to determine the long-term potential for criticality in a repository environment. In all instances the methodology and scenarios used in these analyses are compatible with those developed and used for Commercial Spent Nuclear Fuel (CSNF) and Defense High Level Waste (DHLW), as tailored for the particular …
Date: September 21, 1998
Creator: McClure, J.A.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 6, Ed. 1 Monday, September 21, 1998 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 84, No. 6, Ed. 1 Monday, September 21, 1998

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: September 21, 1998
Creator: Horn, Richard A.
Object Type: Newspaper
System: The Gateway to Oklahoma History
A Silicon Track Trigger for the D0 Experiment in Run II (open access)

A Silicon Track Trigger for the D0 Experiment in Run II

None
Date: September 21, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Status report on the long-term stability of the Advanced Photon Source. (open access)

Status report on the long-term stability of the Advanced Photon Source.

Table 1 summarizes the average elevation changes and standard deviations as well as the points with the largest changes for each year. On average, hardly any settlements can be detected; however, local changes of +2.90 mm to {minus}2.31 mm have been measured. Looking at the low and high points, the settlement process is slowing down over time. Overall, the settlements observed match the expectations for this type of construction. To date no major realignment of the Advanced Photon Source (APS) storage ring has been necessary. The particle beam tracks with the settlements of the floor as long as these changes occur in a smooth fashion and not as sudden discontinuities [5]. From Figures 6 through 8 it is also apparent that settlements affect larger areas in the storage ring and experiment hall that impact the location of the source point as well as the location of the beamline user equipment. The limiting apertures of the insertion device chambers will make realignment of the APS storage ring a necessity at some point in the future. Currently simulations and machine studies we underway to provide an estimate of tolerable settlement limits before a realignment of certain sections of the storage ring would …
Date: September 21, 1998
Creator: Friedsam, H.
Object Type: Article
System: The UNT Digital Library
Structural and magnetic studies of fcc Fe films with self-organized lateral modulation on striped Cu(110)-O(2x1) substrates. (open access)

Structural and magnetic studies of fcc Fe films with self-organized lateral modulation on striped Cu(110)-O(2x1) substrates.

Fcc Fe wedges of 0-12 monolayer (ML) were grown by means of molecular beam epitaxy onto a novel substrate: flat Cu(110) with an oxygen-induced, long-range ordered striped phase, and studied in-situ with medium energy electron diffraction (MEED) and the surface magneto-optical Kerr effect (SMOKE). In contrast to Fe growth on either clean or oxygen-saturated Cu(110), the films on the striped substrates retain a layer-by-layer growth mode up to 6-7 ML and are fcc at least up to 12 ML. In addition, satellite peaks were observed on both sides of the MEED (0,0) streak, indicating a long-range-ordered lateral modulation of the Fe surface. We postulate that the Fe films grow conformally onto the original striped substrate. SMOKE studies show that these fcc Fe wedges are ferromagnetic with an easy axis along the original stripes for Fe thickness &gt; 4ML and a remnant magnetization that increases linearly with thickness beyond 4 ML.
Date: September 21, 1998
Creator: Li, D.
Object Type: Article
System: The UNT Digital Library