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The atmospheric neutrino flavor ratio in Soudan 2.

Description: We have measured the flavor ratio of ratios (R) in atmospheric neutrino interactions using a 1.52 kton-year exposure of Soudan 2. We find R = 0.67 {+-} 0.15{sub {minus}0.06}{sup +0.04}. This value is about 2{sigma} from the expected value of 1.0 and is consistent with the anomalous ratios measured by the Kamiokande and IMB experiments. We note that since our acceptance matrix is different from those of the water Cherenkov experiments we would not expect to measure the same value of R, unless R=… more
Date: October 15, 1997
Creator: Goodman, M.
Partner: UNT Libraries Government Documents Department
open access

Search for AGN neutrinos with the soudan 2 detector.

Description: Several authors have presented models for neutrino production from Active Galactic Nuclei (AGN) that allow for the possibility of AGN neutrinos outnumbering the atmospheric neutrino flux for energies in excess of 30 TeV. The authors present preliminary results from a search for high energy neutrinos from AGN using the underground Soudan 2 Detector.
Date: October 15, 1997
Creator: DeMuth, D. M.
Partner: UNT Libraries Government Documents Department
open access

Nonlinear Rayleigh-Taylor and Richtmyer-Meshkov Mixing Experiments at Nova

Description: The evolution of the Rayleigh-Taylor (RT) and Richtmyer-Meshkov (RM) instabilities in the nonlinear regime of growth was investigated in indirect-drive experiments on the Nova laser. The RT experiments investigated the evolution of both single- and multimode perturbations at an embedded interface, isolated from the effects of ablation. This ``classical`` geometry allows short wavelength ({lambda} {approximately} 10-20 {micro}m) perturbations to grow strongly, in marked contrast to prior results… more
Date: September 15, 1997
Creator: Budil, K. S.; Remington, B. A.; Weber, S. V.; Farley, D.R.; Murray, S. & Peyser, T.A.
Partner: UNT Libraries Government Documents Department
open access

Excitations of the Transversely Polarized Spin Density Waves in Chromium

Description: Inelastic neutron scattering measurements across the TSDW satellites of chromium were performed at {Delta}E=5,20meV, both under zero field and 5T magnetic field. Analysis concerning the transverse magnetic excitations (T{sub 1},T{sub 2}) and the longitudinal magnetic excitations (L) indicates that T{sub 1} and L are equally intense while T{sub 2} dominates and becomes more so at higher energies.
Date: July 15, 1997
Creator: Lee, W. T.; Werner, S. A.; Fernandez-Baca, J. A. & Fishman, R. S.
Partner: UNT Libraries Government Documents Department
open access

Short range rapidity correlations from the Bose-Einstein effect and intermittency: A quantitative demonstration

Description: A measurement of the two-particle correlation of identified pions was performed in the E802/E859 magnetic spectrometer on the interval 1.5 {le} y {le} 2.0, {delta}{phi} = 0.4 rad, for central {sup 28}Si + Au collisions. It is demonstrated that the two-pion correlation in rapidity is entirely due to Bose-Einstein interference. The directly measured exponential correlation length is {zeta}{sub y} = 0.20 {+-} 0.03 for two {pi}{sup {minus}}, with strength R(0,0) {approximately} 1%, in agreement wit… more
Date: May 15, 1997
Creator: Tannenbaum, M.J. & Collaboration, E802 /E859
Partner: UNT Libraries Government Documents Department
open access

High Temperature Structural Behavior of SrRuO{sub 3}

Description: The unusual metal SrRuO{sub 3} is perhaps the only known 4d transition metal based ferromagnet (Tc = 162K) with a sizable moment. To complement low T polarized neutron diffraction measurements of the magnetization density, high T neutron diffraction measurements are reported here. Two structural phase transitions are observed. Between 10K and 800K SrRuO{sub 3} is orthorhombic and at 800K it appears to be tetragonal until 975K, where it becomes cubic. The temperature variation of the lattice par… more
Date: July 15, 1997
Creator: Chakoumakos, B.C., Nagler, S.E., Misture, S.T., Christen, H.M.
Partner: UNT Libraries Government Documents Department
open access

Definition of neutron lifespan and neutron lifetime in MCNP4B

Description: MCNP4B was released in early 1997. In this new version, several major changes were made to the underlying theory used to estimate the non-adjoint-weighted removal, fission, capture, and escape prompt-neutron lifetimes. These four lifetimes are now being calculated in accordance to the neutron-balance theory described by Spriggs et al. in which the non-adjoint-weighted lifetime for a particular type of reaction (i.e., fission, capture, escape, removal, etc.) is defined as the total neutron popul… more
Date: January 15, 1997
Creator: Busch, R. D.; Spriggs, G. D. & Hendricks, J. S.
Partner: UNT Libraries Government Documents Department
open access

Upgrade of the wide-angle neutron diffractometer at the high flux isotope reactor

Description: The Wide-Angle Neutron Diffractometer (WAND) is a flat-cone geometry diffractometer located at the High Flux Reactor (HFIR). This instrument is currently being upgraded. The central part of this upgrade is the development of a new curved one-dimensional position sensitive detector which covers a 125 degree angular range with an effective radius of 71 cm. This detector will be a multi-anode (624 anodes on a 0.2 degree pitch) {sup 3}He gas-filled proportional counter. This totally new system will… more
Date: July 15, 1997
Creator: Katano, S.; Morii, Y. & Child, H.R.
Partner: UNT Libraries Government Documents Department
open access

Deactivating a major nuclear fuels reprocessing facility cost effectively

Description: This paper describes three key processes used in deactivating the Plutonium Uranium Extraction (PUREX) Facility, a large, complex nuclear reprocessing facility, 15 months ahead of schedule and $77 million under budget. The organization was reengineered to refine its business processes and more effectively organize around the deactivation work scope. Multi-disciplined work teams were formed to be self-sufficient and empowered to make decisions and perform work. A number of benefits were realized… more
Date: August 15, 1997
Creator: LeBaron, G. J.
Partner: UNT Libraries Government Documents Department
open access

Optimized filtering of regional and teleseismic seismograms: results of maximizing SNR measurements from the wavelet transform and filter banks

Description: Development of a worldwide network to monitor seismic activity requires deployment of seismic sensors in areas which have not been well studied or may have from available recordings. Development and testing of detection and discrimination algorithms requires a robust representative set of calibrated seismic events for a given region. Utilizing events with poor signal-to-noise (SNR) can add significant numbers to usable data sets, but these events must first be adequately filtered. Source and pa… more
Date: July 15, 1997
Creator: Leach, R. R.; Schultz, C. & Dowla, F.
Partner: UNT Libraries Government Documents Department
open access

Automated leak test systems

Description: An automated leak test system for tritium shipping containers has been developed at Westinghouse Savannah River Co. (WSRC). The leak detection system employs a computer controlled helium detector which allows an operator to enter key information when prompted. The software for controlling the tests and the equipment apparatus were both designed and manufactured at the Savannah River Technology Center within WSRC. Recertification Test: Every twelve months, the pressure vessel portion of the ship… more
Date: September 15, 1997
Creator: Cordaro, J. V.; Thompson, W. D. & Reeves, G.
Partner: UNT Libraries Government Documents Department
open access

Problem free nuclear power and global change

Description: Nuclear fission power reactors represent a solution-in-principle to all aspects of global change possibly induced by inputting of either particulate or carbon or sulfur oxides into the Earth`s atmosphere. Of proven technological feasibility, they presently produce high- grade heat for electricity generation, space heating and industrial process-driving around the world, without emitting greenhouse gases or atmospheric particulates. However, a substantial number of major issues currently stand b… more
Date: August 15, 1997
Creator: Teller, E.; Wood, L.; Nuckolls, J.; Ishikawa, M. & Hyde, R.
Partner: UNT Libraries Government Documents Department
open access

Deployment of pollution prevention during design -- a case study

Description: Traditionally, pollution prevention (P2) assessments have been performed on existing facilities and ongoing operations, well after the completion of design and construction. It has been theorized that more success can be achieved by moving P2 upstream into the design process, where an estimated 70% of a project`s total life cycle costs are initially fixed. Decisions made during design to prevent or minimize the amount of waste generated can reap benefits for many years to come. This is especial… more
Date: August 15, 1997
Creator: Del Mar, R.A.
Partner: UNT Libraries Government Documents Department
open access

Control mechanisms for a nonlinear model of international relations

Description: Some issues of control in complex dynamical systems are considered. The authors discuss two control mechanisms, namely: a short range, reactive control based on the chaos control idea and a long-term strategic control based on an optimal control algorithm. They apply these control ideas to simple examples in a discrete nonlinear model of a multi-nation arms race.
Date: July 15, 1997
Creator: Pentek, A.; Kadtke, J.; Lenhart, S. & Protopopescu, V.
Partner: UNT Libraries Government Documents Department
open access

Guidance document for multi-facility recycle/reuse/free release of metals from radiological control areas

Description: Approximately 15% of the Low Level Waste (LLW) produced at Los Alamos consists of scrap metal equipment and materials. The majority of this material is produced by decommissioning and modification of existing facilities. To address this waste stream, Los Alamos has developed a scrap metal recycling program that is operated by the Environmental Stewardship Office to minimize the amount of LLW metal sent for LLW landfill disposal. Past practice has supported treating all waste metals generated wi… more
Date: August 15, 1997
Creator: Gogol, S. & Starke, T.
Partner: UNT Libraries Government Documents Department
open access

Isolated prompt photon production

Description: We show that the conventionally defined partonic cross section for the production of isolated prompt photons is not an infrared safe quantity. We work out the case of e{sup +}e{sup -} {yields} {gamma} + X in detail, and we discuss implications for hadron reactions such as p{bar p} {yields} {gamma} + X.
Date: August 15, 1997
Creator: Berger, E. L.; Guo, Xiaofeng & Qiu, Jianwei
Partner: UNT Libraries Government Documents Department
open access

Vortex structure in rotating Rayleigh-Benard convection

Description: The authors investigate the flow patterns in a cylindrical rotating Rayleigh-Benard convection cell with radius-to-height ratio {Gamma} = 0.5. The Rayleigh number R is 2 x 10{sup 8}, the dimensionless rotation rate {Omega} varies from 10{sup 4} to 5 x 10{sup 4}, and the convective Rossby number Ro is between 2 and 0.4. Measurements of the velocity field in the volume adjacent to the top of the cell are acquired with a scanning particle image velocimetry (PIV) system. The authors present quantit… more
Date: July 15, 1997
Creator: Vorobieff, P. & Ecke, R.E.
Partner: UNT Libraries Government Documents Department
open access

Rayleigh wave group velocity dispersion across Northern Africa, Southern Europe and the Middle East

Description: THis report presents preliminary results from a large scale study of surface wave group velocity dispersion throughout Northern Africa, the Mediterranean, Southern Europe and the Middle East. Our goal is to better define the 3D lithospheric shear-wave velocity structure within this region by improving the resolution of global surface wave tomographic studies. We hope to accomplish this goal by incorporating regional data at relatively short periods (less than 40 sec), into the regionalization o… more
Date: July 15, 1997
Creator: McNamara, D. E. & Walter, W. R.
Partner: UNT Libraries Government Documents Department
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