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Measurements and Analysis of Helium-Like Triplet Ratios in the X-Ray Spectra of O-Type Stars

Description: We discuss new methods of measuring and interpreting the forbidden-to-intercombination line ratios of helium-like triplets in the X-ray spectra of O-type stars, including accounting for the spatial distribution of the X-ray emitting plasma and using the detailed photospheric UV spectrum. Measurements are made for four O stars using archival Chandra HETGS data. We assume an X-ray emitting plasma spatially distributed in the wind above some minimum radius R{sub 0}. We find minimum radii of format… more
Date: June 19, 2006
Creator: Leutenegger, Maurice A.; Paerels, Frits B. S.; Kahn, Steven M. & Cohen, David H.
Partner: UNT Libraries Government Documents Department
open access

An atmospheric tritium release database for model comparisons

Description: A database of vegetation, soil, and air tritium concentrations at gridded coordinate locations following nine accidental atmospheric releases is described. While none of the releases caused a significant dose to the public, the data collected is valuable for comparison with the results of tritium transport models used for risk assessment. The largest, potential, individual off-site dose from any of the releases was calculated to be 1.6 mrem. The population dose from this same release was 46 per… more
Date: December 19, 1991
Creator: Murphy, C. E. Jr. & Wortham, G. R.
Partner: UNT Libraries Government Documents Department
open access

An atmospheric tritium release database for model comparisons

Description: A database of vegetation, soil, and air tritium concentrations at gridded coordinate locations following nine accidental atmospheric releases is described. While none of the releases caused a significant dose to the public, the data collected is valuable for comparison with the results of tritium transport models used for risk assessment. The largest, potential, individual off-site dose from any of the releases was calculated to be 1.6 mrem. The population dose from this same release was 46 per… more
Date: December 19, 1991
Creator: Murphy, C. E. Jr. & Wortham, G. R.
Partner: UNT Libraries Government Documents Department
open access

IMPROVED GROUND TRUTH IN SOUTHERN ASIA USING IN-COUNTRY DATA, ANALYST WAVEFORM REVIEW, AND ADVANCED ALGORITHMS

Description: A new catalog of seismicity at magnitudes above 2.5 for the period 1923-2008 in the Iran region is assembled from arrival times reported by global, regional, and local seismic networks. Using in-country data we have formed new events, mostly at lower magnitudes that were not previously included in standard global earthquake catalogs. The magnitude completeness of the catalog varies strongly through time, complete to about magnitude 4.2 prior to 1998 and reaching a minimum of about 3.6 during th… more
Date: June 19, 2009
Creator: Engdahl, Eric, R.; Bergman, Eric, A.; Myers, Stephen, C. & Ryall, Floriana
Partner: UNT Libraries Government Documents Department
open access

Miniatuization of the flowing fluid electric conductivity loggingtec hnique

Description: An understanding of both the hydraulic properties of the aquifer and the depth distribution of salts is critical for evaluating the potential of groundwater for conjunctive water use and for maintaining suitable groundwater quality in agricultural regions where groundwater is used extensively for irrigation and drinking water. The electrical conductivity profiles recorded in a well using the flowing fluid electric conductivity logging (FEC logging) method can be analyzed to estimate interval sp… more
Date: October 19, 2005
Creator: Su, Grace W.; Quinn, Nigel W.T.; Cook, Paul J. & Shipp, William
Partner: UNT Libraries Government Documents Department
open access

Scrape-Off Layer Plasmas for ITER with 2nd X-Point and Convective Transport Effects

Description: Plasma fluxes to the divertor region in ITER near the magnetic separatrix have been modeled extensively in the past. The smaller, but potentially very important fluxes to the main chamber and outer divertor regions are the focus of the present paper. Two main additions to the usual transport modeling are investigated: namely, convective radial transport from intermittent, rapidly propagating ''blob'' events, and inclusion of the magnetic flux-surface region beyond the second X-point that actual… more
Date: May 19, 2006
Creator: Rognlien, T; Bulmer, R; Rensink, M & Brooks, J
Partner: UNT Libraries Government Documents Department
open access

Effective Model Calibration of the Geologically Complex Death Valley Regional Ground-Water Flow System, Nevada and California

Description: A numerical ground-water flow model is being constructed for the Death Valley regional ground-water system, an area that encompasses approximately 80,000 km{sup 2} in southern Nevada and southeastern California. Effective construction and calibration of the regional-scale steady-state flow model, developed using MODFLOW-2000, is dependent upon integration of hydrogeologic data and parameter-estimation techniques. A three-dimensional hydrogeologic-framework model of the region was initially cons… more
Date: October 19, 2000
Creator: O'Brien, G. M.; D'Agnese, F. A.; Faunt, C. C. & Belcher, W. R.
Partner: UNT Libraries Government Documents Department
open access

A measurement of the radiation environment in the CDF tracking volume

Description: We present direct measurements of the spatial distribution of both ionizing radiation and low energy neutrons (E{sub n} < 200 keV) inside the tracking volume of the collider detector at Fermilab (CDF). Two types of thermal luminescent dosimeters are used for these measurements. Data collected from exposures with different accelerator conditions allow us to separate the radiation fields into contributions from proton beam losses and from proton-antiproton collisions. Using a simple model of a… more
Date: September 19, 2002
Creator: R. J. Tesarek,S. D'Auria and A. Hocker
Partner: UNT Libraries Government Documents Department
open access

Calculations of the transverse spatial distribution of NE102 scintillation light made by recoil protons from collimated 14-MeV neutrons

Description: A calculation has been made of the spatial distribution of NE102 scintillation light produced by recoil protons from collimated 14-MeV neutron illumination. Results were then averaged over offset circles of various radii, thus determining the fraction of the total scintillation light created inside cylindrical scintillators for uniform neutron illumination over the front face of the scintillator. The results are useful in sensitivity considerations for neutron-imaging camera design.
Date: January 19, 1979
Creator: Goosman, D. R.
Partner: UNT Libraries Government Documents Department
open access

Spatial and Temporal Patterns of Carbon Storage and Species Richness in Three South Carolina Coastal Plain Riparian Forests

Description: Micro-topographic variations in carbon storage and their spatial distribution with respect to vegetation were studied in the Pen Branch system as well as intermediate and late successional forests. Overall measurements of above-ground biomass, soil carbon, and stand structure indicate rapid convergence with the patterns in late successional forests. Micro-site differences were small.
Date: March 19, 1999
Creator: Giese, Laura A.; Aust, W. Michael; Trettin, Carl C. & Kolka, Randall K.
Partner: UNT Libraries Government Documents Department
open access

Drama in Dynamics: Boom, Splash, and Speed

Description: The full nature of chemistry and physics cannot be captured by static calculations alone. Dynamics calculations allow the simulation of time-dependent phenomena. This facilitates both comparisons with experimental data and the prediction and interpretation of details not easily obtainable from experiments. Simulations thus provide a direct link between theory and experiment, between microscopic details of a system and macroscopic observed properties. Many types of dynamics calculations exist. T… more
Date: December 19, 2004
Creator: Netzloff, Heather M.
Partner: UNT Libraries Government Documents Department
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