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A 2.14 ms candidate optical pulsar in SN1987A: Ten years after (open access)

A 2.14 ms candidate optical pulsar in SN1987A: Ten years after

We have monitored Supernova 1987A in optical/near-infrared bands from a few weeks following its birth until the present time in order to search for a pulsar remnant. We have found an apparent pattern of emission near the frequency of 467.5 Hz - a 2.14 ms pulsar candidate, first detected in data taken on the remnant at the Las Campanas Observatory (LCO) 2.5-m Dupont telescope during 14-16 Feb. 1992 UT. We detected further signals near the 2.14 ms period on numerous occasions over the next four years in data taken with a variety of telescopes, data systems and detectors, at a number of ground- and space-based observatories. The sequence of detections of this signal from Feb. `92 through August `93, prior to its apparent subsequent fading, is highly improbable (< 10{sup -10} for any noise source). We also find evidence for modulation of the 2.14 ms period with a {approx}1,000 s period which, when taken with the high spindown of the source (2-3 x 10{sup -10} Hz/s), is consistent with precession and spindown via gravitational radiation of a neutron star with a non- axisymmetric oblateness of {approx}10{sup -6}, and an implied gravitational luminosity exceeding that of the Crab Nebula pulsar by …
Date: September 1, 1997
Creator: Middleditch, J.; Kristian, J. A.; Kunkel, W. E.; Hill, K. M. & Watson, R. D.
Object Type: Article
System: The UNT Digital Library
100-D Ponds closure plan. Revision 1 (open access)

100-D Ponds closure plan. Revision 1

The 100-D Ponds is a Treatment, Storage, and Disposal (TSD) unit on the Hanford Facility that received both dangerous and nonregulated waste. This Closure Plan (Rev. 1) for the 100-D Ponds TSD unit consists of a RCRA Part A Dangerous Waste Permit Application (Rev. 3), a RCRA Closure Plan, and supporting information contained in the appendices to the plan. The closure plan consists of eight chapters containing facility description, process information, waste characteristics, and groundwater monitoring data. There are also chapters containing the closure strategy and performance standards. The strategy for the closure of the 100-D Ponds TSD unit is clean closure. Appendices A and B of the closure plan demonstrate that soil and groundwater beneath 100-D Ponds are below cleanup limits. All dangerous wastes or dangerous waste constituents or residues associated with the operation of the ponds have been removed, therefore, human health and the environment are protected. Discharges to the 100-D Ponds, which are located in the 100-DR-1 operable unit, were discontinued in June 1994. Contaminated sediment was removed from the ponds in August 1996. Subsequent sampling and analysis demonstrated that there is no contamination remaining in the ponds, therefore, this closure plan is a demonstration of clean …
Date: September 1, 1997
Creator: Petersen, S.W.
Object Type: Report
System: The UNT Digital Library
A 600-kV double-pulser for the PHERMEX electron gun (open access)

A 600-kV double-pulser for the PHERMEX electron gun

The PHERMEX (Pulsed High Energy Radiographic Machine Emitting X-rays) Radiographic Facility is a 50-MHz, 3-Cavity, RF-Linac driven by a pulsed, thermionic electron-gun Injector. The PHERMEX is used to take flash radiographs using x-rays at a single time in an explosively driven event. To investigate the time evolution of these events requires two things: (1) a multiple-pulser to drive the electron-gun Injector and (2) a large-format, gamma-ray, camera system to record a scintillator at the different times. The authors report the recent success of developing a reliable double-pulser that consists of two Marx generators that independently charge two PFLs that are switched out at about 1.4 MV. The PFLs are connected in series by large diaphragm switches that are independently laser triggered by two quadrupled-YAG lasers. Recent tests of the system into a dummy load, produced two high quality 600 kV pulses separated by 1.0 {micro}s. Each pulse has a FWHM of 90 ns, a 50 ns flat-top {+-} 3%, and a risetime of 25 ns and a falltime of 35 ns. The interpulse time is variable up to about 275 {micro}s; the first switch is kept closed by a keep alive inductor. The system has produced a 50 shot sequence …
Date: September 1, 1997
Creator: Carlson, R. L.; Kang, M.; Melton, J. G.; Seitz, G. J. & Trujillo, L. T.
Object Type: Article
System: The UNT Digital Library

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History

121st Annual Ponca Pow Wow

Photograph of the 121st Annual Ponca Pow Wow at White Eagle Park in Ponca City, OK. Photo by Mary Huffman, Sept. 1, 1997.
Date: September 1, 1997
Creator: Huffman, Mary
Object Type: Photograph
System: The Gateway to Oklahoma History
1996 LMITCO environmental monitoring program report for the Idaho National Engineering and Environmental Laboratory (open access)

1996 LMITCO environmental monitoring program report for the Idaho National Engineering and Environmental Laboratory

This report describes the calendar year 1996 environmental surveillance and compliance monitoring activities of the Lockheed Martin Idaho Technologies Company Environmental Monitoring Program performed at the Idaho National Engineering and Environmental Laboratory (INEEL). Results of sampling performed by the Radiological Environmental Surveillance, Site Environmental Surveillance, Drinking Water, Effluent Monitoring, Storm Water Monitoring, Groundwater Monitoring, and Special Request Monitoring Programs are included in this report. The primary purposes of the surveillance and monitoring activities are to evaluate environmental conditions, to provide and interpret data, to verify compliance with applicable regulations or standards, and to ensure protection of human health and the environment. This report compares 1996 data with program-specific regulatory guidelines and past data to evaluate trends.
Date: September 1, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
1996 Site environmental report. Volume I (open access)

1996 Site environmental report. Volume I

This report summarizes environmental activities at the Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) for 1996. It presents data and information that characterize the Laboratory`s environmental management performance measured against applicable regulatory standards and DOE requirements. The report also discusses significant highlights of Berkeley Lab`s environmental programs. The format and content of the report satisfy the requirements set forth in applicable sections of U.S. Department of Energy (DOE) Order 231.1, Environment, Safety and Health Reporting, and included in the contract between the University of California (UC) and The DOE.
Date: September 1, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
1996 Site environmental report. Volume II (open access)

1996 Site environmental report. Volume II

Ernest Orlando Lawrence Berkeley National Laboratory presents Volume II, data appendix as a reference document to supplement the 1996 Site Environmental Report. Volume II contains the raw environmental monitoring and sampling data used to generate many of the summary results included in the main report for both routine and nonroutine activities. This appendix includes a legend that cross-references the enclosed data tables with summary tables in the main report. The legend also provides a listing of more detailed descriptions for the station location codes used in the appendices` tables. Data presented in the tables are given in Systeme International (SI) units. The glossary found in the main report contains a listing of the SI units.
Date: September 1, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
1996 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites (open access)

1996 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in the US. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included in this report are tables showing the distribution of waste by state for 1996 and a comparison of waste volumes and radioactivity by state for 1992 through 1996; also included is a list of all commercial nuclear power reactors in the US as of December 31, 1996. This report distinguishes between low-level radioactive waste shipped directly for disposal by generators and waste that was handled by an intermediary, a reporting change introduced in the 1988 state-by-state report.
Date: September 1997
Creator: Fuchs, R. L.
Object Type: Report
System: The UNT Digital Library
1997 structural integrity assessments for the Category C liquid low-level waste tank systems at Oak Ridge National Laboratory, Oak Ridge, Tennessee (open access)

1997 structural integrity assessments for the Category C liquid low-level waste tank systems at Oak Ridge National Laboratory, Oak Ridge, Tennessee

This report presents the results of a series of evaluations to determine if the individual Category C tank systems retain sufficient structural integrity to continue being used for liquid storage. The approach used to reach the final certification/conclusion consisted of three phases, including: (1) Review of the original engineering design drawings and construction materials to determine whether the tank and line systems were capable of containing liquids without leaking (and also to check that the construction materials were compatible with liquids that might have been placed in these systems). While drawings in this report may be of poor quality, they are copies of the best available originals. (2) A qualitative corrosion assessment conducted in 1995 that further evaluated both the potential internal corrosion effects of materials in the tank and in the potential external corrosion effects of the backfill and native soil at the Oak Ridge National Laboratory (ORNL). The ability to accurately measure or predict the amount of corrosion present on both the internal and external walls of the tanks and pipelines is extremely limited. However, when available, data were used to assess the historical tank contents and usage and the probable corrosive effects on the tank system materials …
Date: September 1, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
1997 U.S. Department of Energy Strategic Plan (open access)

1997 U.S. Department of Energy Strategic Plan

With the end of the Cold War and the election of President Clinton, the Department of Energy (DOE) set a new course which began with the publication of its first departmental strategic plan in April 1994. Entitled ``Fueling a Competitive Economy, it provided the framework and shared vision for meeting responsibilities in energy, national security, environmental quality, and science and technology. The strategic plan was the guidepost for the formulation of the Department`s FY 1996, FY 1997, and FY 1998 budgets and was critical to the development of the Department`s Strategic Alignment Initiative, designed to save $1.7 billion over five years. This current plan, which has been significantly improved through a very close consultation process with Congress and customers stakeholders, takes DOE to the next important performance level by being more directly linked to actions and results. It defines a strategic goal for each of the Department`s four business lines and, in the spirit of the Government Performance and Results Act and the National Performance Review, identifies a fifth goal addressing corporate management. Reengineering the business practices, managing for results, being open with neighbors and stakeholders, and ensuring the safety and health of DOE workers and the public are, and …
Date: September 1997
Creator: unknown
Object Type: Text
System: The UNT Digital Library
6th International Meshing Roundtable '97 (open access)

6th International Meshing Roundtable '97

The goal of the 6th International Meshing Roundtable is to bring together researchers and developers from industry, academia, and government labs in a stimulating, open environment for the exchange of technical information related to the meshing process. In the pas~ the Roundtable has enjoyed significant participation born each of these groups from a wide variety of countries. The Roundtable will consist of technical presentations from contributed papers and abstracts, two invited speakers, and two invited panels of experts discussing topics related to the development and use of automatic mesh generation tools. In addition, this year we will feature a "Bring Your Best Mesh" competition and poster session to encourage discussion and participation from a wide variety of mesh generation tool users. The schedule and evening social events are designed to provide numerous opportunities for informal dialog. A proceedings will be published by Sandia National Laboratories and distributed at the Roundtable. In addition, papers of exceptionally high quaIity will be submitted to a special issue of the International Journal of Computational Geometry and Applications. Papers and one page abstracts were sought that present original results on the meshing process. Potential topics include but are got limited to: Unstructured triangular and tetrahedral …
Date: September 1, 1997
Creator: White, D.
Object Type: Report
System: The UNT Digital Library
Aberration analysis calculations for synchrotron radiation beamline design (open access)

Aberration analysis calculations for synchrotron radiation beamline design

The application of ray deviation calculations based on aberration coefficients for a single optical surface for the design of beamline optical systems is reviewed. A systematic development is presented which allows insight into which aberration may be causing the rays to deviate from perfect focus. A new development allowing analytical calculation of line shape is presented.
Date: September 1, 1997
Creator: McKinney, W.R.; Howells, M. & Padmore, H.A.
Object Type: Article
System: The UNT Digital Library
Abilene Philharmonic Playbill: September 27-November 1, 1997 (open access)

Abilene Philharmonic Playbill: September 27-November 1, 1997

Program for Abilene Philharmonic concerts performed on September 27th (first concert, classical) and November 1st (second concert, pops) during the 48th season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: September 1997
Creator: Abilene Philharmonic
Object Type: Book
System: The Portal to Texas History
AC magnetic field losses in BSCCO-2223 superconducting tapes (open access)

AC magnetic field losses in BSCCO-2223 superconducting tapes

The AC magnetic losses at power frequencies (60 Hz) were investigated for mono- and multifilament Ag-sheathed (Bi, Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y} (BSCCO-2223) tapes with similar transport critical current (I{sub c}) values at 77 K. The multifilament sample exhibited higher losses than the monofilament under the same conditions. Loss peaks are discussed in terms of intergranular, intragranular and eddy current losses. Because of BSCCO`s anisotropy, field orientation has a large effect on the magnitude of these peaks, even at relatively small angles. Losses for fields applied parallel to the c-axis of the textured BSCCO grains are larger by more than one order of magnitude than those applied perpendicular.
Date: September 1, 1997
Creator: Lelovic, M.; Mench, S. & Deis, T.
Object Type: Article
System: The UNT Digital Library
Accelerator mass spectrometry as a bioanalytical tool for nutritional research (open access)

Accelerator mass spectrometry as a bioanalytical tool for nutritional research

Accelerator Mass Spectrometry is a mass spectrometric method of detecting long-lived radioisotopes without regard to their decay products or half-life. The technique is normally applied to geochronology, but recently has been developed for bioanalytical tracing. AMS detects isotope concentrations to parts per quadrillion, quantifying labeled biochemicals to attomole levels in milligram- sized samples. Its advantages over non-isotopeic and stable isotope labeling methods are reviewed and examples of analytical integrity, sensitivity, specificity, and applicability are provided.
Date: September 1997
Creator: Vogel, J. S. & Turteltaub, K. W.
Object Type: Article
System: The UNT Digital Library