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Coupling MCNP-DSP and LAHET Monte Carlo Codes for Designing Subcriticality Monitors for Accelerator-Driven Systems (open access)

Coupling MCNP-DSP and LAHET Monte Carlo Codes for Designing Subcriticality Monitors for Accelerator-Driven Systems

The design of reactivity monitoring systems for accelerator-driven systems must be investigated to ensure that such systems remain subcritical during operation. The Monte Carlo codes LAHET and MCNP-DSP were combined together to facilitate the design of reactivity monitoring systems. The coupling of LAHET and MCNP-DSP provides a tool that can be used to simulate a variety of subcritical measurements such as the pulsed neutron, Rossi-{alpha}, or noise analysis measurements.
Date: October 23, 2000
Creator: Valentine, T.E.; Rugama, Y. Munoz-Cobos, J. & Perez, R.
Object Type: Article
System: The UNT Digital Library
UNIFORM SEMICLASSICAL APPROXIMATION IN QUANTUM STATISTICAL MECHANICS. (open access)

UNIFORM SEMICLASSICAL APPROXIMATION IN QUANTUM STATISTICAL MECHANICS.

We present a simple method to deal with caustics in the semiclassical approximation to the partition function of a one-dimensional quantum system. The procedure, which makes use of complex trajectories, is applied to the quartic double-well potential.
Date: October 23, 2000
Creator: De Carvalho, C.A.A.; Cavalcanit, R.M.; Fraga, E.S. & Joras, S.E.
Object Type: Article
System: The UNT Digital Library
A study of the Delta I = 1/2 rule in the weak decay of S-shell hypernuclei: BNL E931 (open access)

A study of the Delta I = 1/2 rule in the weak decay of S-shell hypernuclei: BNL E931

It is empirically observed that the non-leptonic decay of strange hadrons is enhanced when the change in isospin is 1/2. This is generalized in the ''{Delta}I = 1/2 rule'' that states that all such decays proceed predominantly through {Delta}I = 1/2 amplitudes. However, there is no definitive explanation for this apparently universal rule. Non-mesonic decay of {Lambda}-hypernuclei can occur through a weak decay process {Lambda}N {r_arrow} {eta}N. When stimulated by a neutron, two neutrons are emitted from the nucleus, and when stimulated by a proton, a proton and neutron are emitted. By measuring the relative decay widths ({Gamma}{sub n}/{Gamma}{sub p}) in the full set of s-shell hypernuclei, a sensitive test of the {Delta}I = 1/2 rule, and the determination of its applicability to non-mesonic decays can be made. In addition, information about the spin-isospin dependence of the weak decay process can be extracted. A measurement of {Gamma}{sub n}/{Gamma}{sub p}, to an accuracy of even 50% will be sufficient to address important issues relating to the {Delta}I = 1/2 rule and to the weak decay process. The experiment will measure the ratio {Gamma}{sub n}/{Gamma}{sub p}, following the decay of {sup 4}H which is produced by a stopped K{sup {minus}} beam in …
Date: October 23, 2000
Creator: GILL,R.L., FOR THE E931 COLLABORATION.
Object Type: Article
System: The UNT Digital Library
Tandem Terminal Ion Source (open access)

Tandem Terminal Ion Source

OAK-B135 Tandem Terminal Ion Source. The terminal ion source (TIS) was used in several experiments during this reporting period, all for the {sup 7}Be({gamma}){sup 8}B experiment. Most of the runs used {sup 1}H{sup +} at terminal voltages from 0.3 MV to 1.5 MV. One of the runs used {sup 2}H{sup +} at terminal voltage of 1.4 MV. The other run used {sup 4}He{sup +} at a terminal voltage of 1.37 MV. The list of experiments run with the TIS to date is given in table 1 below. The tank was opened four times for unscheduled source repairs. On one occasion the tank was opened to replace the einzel lens power supply which had failed. The 10 kV unit was replaced with a 15 kV unit. The second time the tank was opened to repair the extractor supply which was damaged by a tank spark. On the next occasion the tank was opened to replace a source canal which had sputtered away. Finally, the tank was opened to replace the discharge bottle which had been coated with aluminum sputtered from the exit canal.
Date: October 23, 2000
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Quarterly Technical Progress Report of Radioisotope Power System Materials Production and Technology Program tasks for April 2000 through June 2000 (open access)

Quarterly Technical Progress Report of Radioisotope Power System Materials Production and Technology Program tasks for April 2000 through June 2000

The Office of Space and Defense Power Systems (OSDPS) of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. For the Cassini Mission, for example, ORNL was involved in the production of carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVSs) and weld shields (WSs). This quarterly report has been divided into three sections to reflect program guidance from OSDPS for fiscal year (FY) 2000. The first section deals primarily with maintenance of the capability to produce flight quality carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, clad vent sets (CVSs), and weld shields (WSs). In all three cases, production maintenance is assured by the manufacture of limited quantities of flight quality (FQ) components. The second section deals with several …
Date: October 23, 2000
Creator: Moore, J.P.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, October 23, 2000 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, October 23, 2000

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: October 23, 2000
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Office of River Protection (ORP) Monthly Performance Report for July 2000 (open access)

Office of River Protection (ORP) Monthly Performance Report for July 2000

River Protection Project (RPP) performance for the month of July 2000 was very good. The most significant accomplishments that occurred during the month include the following: The Interim Stabilization Project pumped approximately 30,000 gallons from four tanks. Project-to-date (since June 1998) volume pumped is approximately 808,000 gallons. Five tanks have been interim stabilized this fiscal year, and tanks 241-S-106,241-U-103, and 241-U-105 are being evaluated to determine if the stabilization criteria have been met. Out of the 149 single-shell tanks (SSTs), 124 tanks have been stabilized. Pumping this waste from the single-shell tanks to more secure double-shell tanks (DSTs) supports stabilization of the waste tanks and mitigates leakage to the environment. The Interim Stabilization Project is planned to complete by September 2004. Waste Characterization obtained one grab sample in the month of July 2000. A total of 14 core samples, 12 grab samples, and 6 vapor samples have been taken fiscal year-to-date (FYTD) in support of three key FY 2000 sampling milestones. The Waste Treatment Plant Design and Operation organizations have been developed and staffed, including transitioning BNFL Inc./Bechtel National Inc. employees to CHG. Since the termination of the BNFL contract, CHG has temporarily assumed the work scope for design and …
Date: October 23, 2000
Creator: Wagnild, K. J.
Object Type: Report
System: The UNT Digital Library

Ensemble: 2000-10-23 - Les Petits Violons

Access: Use of this item is restricted to the UNT Community
Ensemble concert performed at the UNT College of Music.
Date: October 23, 2000
Creator: Les Petits Violons
Object Type: Sound
System: The UNT Digital Library

Ensemble: 2000-10-23 - UNT Men's and UNT Women's Chorus

Access: Use of this item is restricted to the UNT Community
Concert presented at the UNT College of Music.
Date: October 23, 2000
Creator: University of North Texas. Men's Chorus.
Object Type: Sound
System: The UNT Digital Library
Executive Order 12919: Emergency Powers of the President (open access)

Executive Order 12919: Emergency Powers of the President

Executive Order 12919 concerns industrial preparedness during times of war and national emergency. This brief report uses simple language to describe what Executive Order 12919 does. It is intended to clarify common misunderstandings about the Order’s purpose and scope.
Date: October 23, 2000
Creator: Burdette, Robert B.
Object Type: Report
System: The UNT Digital Library
Final report for: Fundamental study of long-short interfacial wave interactions with application for flow regime development (open access)

Final report for: Fundamental study of long-short interfacial wave interactions with application for flow regime development

The long waves that cause slugs almost always form more slowly than short waves, and linear stability always predicts that the growth rate for long waves is much less than that for short waves. However, at many conditions above neutral stability, long waves dominate the wave field. Three different studies were undertaken as part of the funded work: (1) linear interaction for unsteady flows; (2) wave evolution in oil-water channel flows; (3) retrograde stability and subcritical bifurcations. The oil-water system was used as a surrogate for gas-liquid systems because the gas phase is usually turbulent, and this complication is thus avoided although the phenomena involved are similar. The following overall conclusions about flow regime development were reached: (a) Oscillations in pressure and flow rate, due to interfacial waves or a malfunctioning pump, can cause significant growth rate changes in short waves within narrow frequency ranges, but probably do not have a large effect on long waves and thus regime transition. (b) Linear and nonlinear processes act together to cause regime transitions; however, it is almost certain that long waves cannot form solely by nonlinear energy transfer from shorter waves. (c) The nonlinear coefficient spectrum contains the information necessary to tell …
Date: October 23, 2000
Creator: McCready, Mark
Object Type: Report
System: The UNT Digital Library
Daily Journal (Perry, Okla.), Vol. 107, No. 208, Ed. 1 Monday, October 23, 2000 (open access)

Daily Journal (Perry, Okla.), Vol. 107, No. 208, Ed. 1 Monday, October 23, 2000

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: October 23, 2000
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
[Mentor Review Document for Camille Hornbeck, Bill Parks, Kari Huse, and Barbara Krishnan at Daggett School by Mentor Nancy Walkup] (open access)

[Mentor Review Document for Camille Hornbeck, Bill Parks, Kari Huse, and Barbara Krishnan at Daggett School by Mentor Nancy Walkup]

A comprehensive mentor review conducted by Nancy Walkup for educators Camille Hornbeck, Bill Parks, Kari Huse, and Barbara Krishnan at Daggett School.
Date: October 23, 2000
Creator: unknown
Object Type: Report
System: The UNT Digital Library