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Absolute Intensities of the Vacuum Ultraviolet Spectra in a Metal-Etch Plasma Processing Discharge

Description: In this paper we report absolute intensities of vacuum ultraviolet and near ultraviolet emission lines (4.8 eV to 18 eV ) for aluminum etching discharges in an inductively coupled plasma reactor. We report line intensities as a function of wafer type, pressure, gas mixture and rf excitation level. IrI a standard aluminum etching mixture containing C12 and BC13 almost all the light emitted at energies exceeding 8.8 eV was due to neutral atomic chlorine. Optical trapping of the WV radiation in the discharge complicates calculations of VUV fluxes to the wafer. However, we see total photon fluxes to the wailer at energies above 8.8 eV on the order of 4 x 1014 photons/cm2sec with anon- reactive wafer and 0.7 x 10 `4 photons/cm2sec with a reactive wtier. The maj ority of the radiation observed was between 8.9 and 9.3 eV. At these energies, the photons have enough energy to create electron-hole pairs in Si02, but may penetrate up to a micron into the Si02 before being absorbed. Relevance of these measurements to vacuum-W photon-induced darnage of Si02 during etching is discussed.
Date: December 9, 1998
Creator: Aragon, B.P.; Blain, M.G.; Hamilton, T.W.; Jarecki, R.L. & Woodworth, J.R.
Partner: UNT Libraries Government Documents Department

High flux isotope reactor redesigned beryllium reflector thermal stress calculations

Description: The Beryllium reflector of the High Flux Isotope Reactor is currently redesigned for upgrading the capability of the reactor. The original design criteria are adopted in the redesign analysis. Both nuclear heating and thermal stress calculations are revised. The results show that more margin of safety have been achieved and the updated design assures more precise design estimates for the reflector thermal stress conditions. 1 ref., 2 figs., 2 tabs.
Date: June 1, 1996
Creator: Chang, S.J.
Partner: UNT Libraries Government Documents Department

Proposed Methodology for Establishing Area of Applicability

Description: This paper presents the application of sensitivity and uncertainty (S/U) analysis methodologies to the data validation tasks of a criticality safety computational study. The S/U methods presented are designed to provide a formal means of establishing the area (or range) of applicability for criticality safety data validation studies. The development of parameters that are analogous to the standard trending parameters form the key to the technique. These parameters are the so-called D parameters, which represent the differences by energy group of S/U-generated sensitivity profiles, and c parameters, which are the k correlation coefficients, each of which give information relative to the similarity between pairs of selected systems. The use of a Generalized Linear Least-Squares Methodology (GLLSM) tool is also described in this paper. These methods and guidelines are also applied to a sample validation for uranium systems with enrichments greater than 5 wt %.
Date: September 20, 1999
Creator: Broadhead, B. L.; Hopper, C. M. & Parks, C. V.
Partner: UNT Libraries Government Documents Department

SCALE Graphical Developments for Improved Criticality Safety Aalyses

Description: New computer graphic developments at Oak Ridge National Ridge National Laboratory (ORNL) are being used to provide visualization of criticality safety models and calculational results as well as tools for criticality safety analysis input preparation. The purpose of this paper is to present the status of current development efforts to continue to enhance the SCALE (Standardized Computer Analyses for Licensing Evaluations) computer software system. Applications for criticality safety analysis in the areas of 3-D model visualization, input preparation and execution via a graphical user interface (GUI), and two-dimensional (2-D) plotting of results are discussed.
Date: September 20, 1999
Creator: Barnett, D. L.; Bowman, S. M.; Horwedel, J. E. & Petrie, L. M.
Partner: UNT Libraries Government Documents Department

Time delays between core power production and external detector response from Monte Carlo calculations

Description: One primary concern for design of safety systems for reactors is the time response of external detectors to changes in the core. This paper describes a way to estimate the time delay between the core power production and the external detector response using Monte Carlo calculations and suggests a technique to measure the time delay. The Monte Carlo code KENO-NR was used to determine the time delay between the core power production and the external detector response for a conceptual design of the Advanced Neutron Source (ANS) reactor. The Monte Carlo estimated time delay was determined to be about 10 ms for this conceptual design of the ANS reactor.
Date: August 1, 1996
Creator: Valentine, T. E. & Mihalczo, J. T.
Partner: UNT Libraries Government Documents Department

Pulsed reactor experiments at Oak Ridge

Description: This paper describes dynamic experiments for 3 pulsed reactors. 1st reactor was pulsed from some average power by rotating a partial Be reflector past an unreflected core face; the other 2 reactors were pulsed by rapid insertion of a fuel rod into the unmoderated and unreflected reactor at essentially zero neutron level with no significant neutron source present. The first reactor was a mockup of an EURATOM design (never constructed) of the proposed SORA Reactor, and the other two were the Health Physics Research Reactor and the Army Pulse Radiation Facility Reactor (APRFR). This paper describes the experiments performed in initial testing of these systems, including destructive tests of APRFR, to set operating limits for this type of reactor in pulsed operation. All the experiments described were performed at the Oak Ridge Critical Experiments Facility.
Date: December 31, 1994
Creator: Mihalczo, J.T.
Partner: UNT Libraries Government Documents Department

Supplying the nuclear arsenal: Production reactor technology, management, and policy, 1942--1992

Description: This book focuses on the lineage of America`s production reactors, those three at Hanford and their descendants, the reactors behind America`s nuclear weapons. The work will take only occasional sideways glances at the collateral lines of descent, the reactor cousins designed for experimental purposes, ship propulsion, and electric power generation. Over the decades from 1942 through 1992, fourteen American production reactors made enough plutonium to fuel a formidable arsenal of more than twenty thousand weapons. In the last years of that period, planners, nuclear engineers, and managers struggled over designs for the next generation of production reactors. The story of fourteen individual machines and of the planning effort to replace them might appear relatively narrow. Yet these machines lay at the heart of the nation`s nuclear weapons complex. The story of these machines is the story of arming the winning weapon, supplying the nuclear arms race. This book is intended to capture the history of the first fourteen production reactors, and associated design work, in the face of the end of the Cold War.
Date: January 1, 1994
Creator: Carlisle, R.P. & Zenzen, J.M.
Partner: UNT Libraries Government Documents Department

Four in. three jaw type connector suitable for vertical mounting sample for job 11

Description: As authorized by purchase order No. 11-2532 dated March 11, 1949 of the Kellex Corp., the first sample of a 4 inch three jaw type connector for Job 11 was fabricated. The design of the connector was per Crane Co. drawing DR-25126-D except vertical mounting. The materials were per Crane Co. drawing A-24491-C. As instructed in verbal conversation with Dr. D.D. Jacobus and as requested in Mr. J.J. Cuniffe`s letter of May 6, 1949, and Ingersoll-Rand Company`s 1 1/4 inch 534 impact wrench with suitable socket to fit the hexagon head of the operating screw of the 4 inch connector was procured on loan to make some preliminary tests. Engineering drawings are listed in a second report on the data base.
Date: July 8, 1949
Creator: Grubbe, A.C.
Partner: UNT Libraries Government Documents Department