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Thomas Jefferson National Accelerator Facility Institutional Plan FY2000 - FY2004

Description: Jefferson Lab contributes to the Department of Energy mission to develop and operate major cutting-edge scientific user facilities. Jefferson Lab's CEBAF (Continuous Electron Beam Accelerator Facility) is a unique tool for exploring the transition between the regime where strongly interacting (nuclear) matter can be understood as bound states of protons and neutrons, and the regime where the underlying fundamental quark-and-gluon structure of matter is evident. The nature of this transition is at the frontier of the authors understanding of matter. Experiments proposed by 834 scientists from 146 institutions in 21 countries await beam time in the three halls. The authors user-customers have been delighted with the quality of the data they are obtaining. Driven by their expressed need for energies higher than the 4 GeV design energy and on the outstanding performance of their novel superconducting accelerator, the laboratory currently delivers beams at 5.5 GeV and expects to deliver energies approaching 6 GeV for experiments in the near future. Building on the success of Jefferson Lab and continuing to deliver value for the nation's investment is the focus of Jefferson Lab's near-term plans. The highest priority for the facility is to execute its approved experimental program to elucidate the quark structure of matter. The Lab plans to participate in the Strategic Simulation Initiative and benefit from the scientific opportunities that it affords. Initially, the lab will contribute its expertise in simulations for nuclear theory and accelerators, data handling, and distributed systems. As part of its SSI activities, the lab is planning to enhance its expertise in lattice QCD and simulations of photon-driven materials and chemical processes.
Date: January 1, 2000
Creator: Lab, Jefferson
Partner: UNT Libraries Government Documents Department

FY 2000 Annual Report for EMSP Project No.70108 - Effects of Fluid Distribution on Measured Geophysical Properties for Partially Saturated, Shallow Subsurface Conditions

Description: Our goal is to improve geophysical imaging of the vadose zone. We will achieve this goal by providing new methods to improve interpretation of field data. The purpose of this EMSP project is to develop relationships between laboratory measured geophysical properties and porosity, saturation, and fluid distribution, for partially saturated soils. Algorithms for relationships between soil composition, saturation, and geophysical measurements will provide new methods to interpret geophysical field data collected in the vadose zone at sites such as Hanford, WA. This report summarizes work after 10 months of a 3-year project. We have modified a laboratory ultrasonics apparatus developed in a previous EMSP project (No.55411) so that we can make velocity measurements for partially-saturated samples rather than fully-saturated or dry samples. We are testing the measurement apparatus using standard laboratory sand samples such as Ottawa sand samples. Preliminary results indicate that we can measure both compressional and shear velocities in these sand samples. We have received Hanford soil samples (sands from split-spoon cores from an uncontaminated site) and expect to make ultrasonic measurements on them also. We have used the LLNL x-ray facility to perform x-ray computed tomography (XCT) imaging for several partially-saturated Ottawa sand and Lincoln sand samples, and have also used the DOE Advance Photon Source at Argonne National Laboratory to make higher-resolution images of some sand samples. Preliminary results indicate that we can image amount and distribution of fluids in homogeneous sand samples. Continuing work from the previous EMSP project, we are testing a new data analysis method for seismic data that is expected to improve interpretation of seismic data from the vadose zone by showing how partial saturation affects seismic parameters. Our results suggest that the planned approach for this research is appropriate, that microstructure is an important factor for measured geophysical properties, and that ...
Date: August 30, 2000
Creator: Berge, P.A.; Bonner, B.P.; Roberts, J.J.; Wildenschild, D.; Aracne-Ruddle, C.M.; Berryman, J.G. et al.
Partner: UNT Libraries Government Documents Department