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LLNL`s regional seismic discrimination research

Description: The ability to negotiate and verify a Comprehensive Test Ban Treaty (CTBT) depends in part on the ability to seismically detect and discriminate between potential clandestine underground nuclear tests and other seismic sources, including earthquakes and mining activities. Regional techniques are necessary to push detection and discrimination levels down to small magnitudes, but existing methods of event discrimination are mainly empirical and show much variability from region to region. The goals of Lawrence Livermore National Laboratory`s (LLNL`s) regional discriminant research are to evaluate the most promising discriminants, improve our understanding of their physical basis and use this information to develop new and more effective discriminants that can be transported to new regions of high monitoring interest. In this report we discuss our preliminary efforts to geophysically characterize two regions, the Korean Peninsula and the Middle East-North Africa. We show that the remarkable stability of coda allows us to develop physically based, stable single station magnitude scales in new regions. We then discuss our progress to date on evaluating and improving our physical understanding and ability to model regional discriminants, focusing on the comprehensive NTS dataset. We apply this modeling ability to develop improved discriminants including slopes of P to S ratios. We find combining disparate discriminant techniques is particularly effective in identifying consistent outliers such as shallow earthquakes and mine seismicity. Finally we discuss our development and use of new coda and waveform modeling tools to investigate special events.
Date: July 1, 1995
Creator: Walter, W.R.; Mayeda, K.M. & Goldstein, P.
Partner: UNT Libraries Government Documents Department

Maximum likelihood borehole corrections for dual-detector density logs

Description: This report discusses Dual-detector density logs which have been used in the petroleum industry for years. The tool was designed with a second detector to allow compensation for the effect of a layer of mudcake between the tool and the formation being measured. The compensation algorithm commonly used calculates the correction to apply to the density measured by the long-spaced detector as proportional to the difference in the densities measured by the two detectors. The coefficient of proportionality is determined from experimental data taken with the tool in a fluid-filled hole of 15 to 40 cm diameter, with uniform thickness sheets of various materials simulating the mudcake. In applying this technology for the Containment program at the Department of Energy Nevada Test Site (NTS) we have discovered two problems. First, we frequently log in air-filled holes much larger than 40 cm. Second, the gap, or layer, is rarely uniform with depth or vertical position on the face of the tool. We have developed a method to determine the proper amount of correction dynamically. No experimental data on the gap effect are needed as long as the two detectors are calibrated to read the proper density when the gap is zero. The method assumes that the form of the equation used in the standard algorithm is correct, but uses the variation of the two density signals with depth to determine the appropriate value of the coefficient, assuming true density varies more slowly than the gap effects. This new, maximum likelihood, method appears to work better than the standard method in both fluid and air-filled holes where the borehole wall is rough and no mudcake is present. It cannot, however, correct for a uniform mudcake or air gap, and so complements but does not replace the standard method.
Date: October 1, 1993
Creator: Carlson, R.C.
Partner: UNT Libraries Government Documents Department

Cold war historic properties of the 21st Space Wing Air Force Space Command

Description: A Legacy-funded inventory and evaluation of facilities dating to the Cold War era was conducted for the USAF 21{sup ST} Space Wing (AFSPC). The mission of the Wing includes early warning of missile launches and detection and tracking of space objects. The political and military strategic context for these facilities was developed through an overview of Cold War history, subdivided into four major periods: (1) origins of the conflict, (2) confrontation and crisis, (3) sustained superpower balance based on mutual deterrence, and (4) renewed confrontation and collapse of the Soviet Union. The enormous importance of early warning systems in maintaining the balance of power between the USA and the Soviet Union is discussed in more detail as a subset of the general context of the Cold War history to provide additional background for evaluating the 21{sup ST} Space Wing systems. In addition, a history of each installation was prepared and placed in the context of the broader history of the Cold War. For instance, the effort to develop a credible nuclear threat in the early 1950s is represented by the construction of Thule AB as a forward bomber base in 1951. The growing concern with a Soviet ICBM threat in the late 1950s is reflected in the construction of BMEWS at Thule AB and Clear AS during 1958-1961. Development of an antiballistic missile (ABM) system, subsequently abandoned during the 1970s, is represented by the Safeguard System at Cavalier AS. The U.S. response to the Soviet submarine-launched missile capability during the 1970s is embodied in the deployment of phased-array radar systems to cover the ocean flanks of North America at Cape Cod AS (and later at Eldorado AS). The establishment of AFSPC at Peterson AFB in 1982 reflects the increased strategic importance of space in the later phases of the Cold ...
Date: March 1, 1996
Creator: Hoffecker, J.F.; Whorton, M. & Buechler, C.R.
Partner: UNT Libraries Government Documents Department

The waveform correlation event detection system project: Issues in system refinement, tuning, and operation

Description: The goal of the Waveform Correlation Event Detection System (WCEDS) Project at Sandia Labs has been to develop a prototype of a full-waveform correlation based seismic event detection system which could be used to assess potential usefulness for CTBT monitoring. The current seismic event detection system in use at the IDC is very sophisticated and provides good results but there is still significant room for improvement, particularly in reducing the number of false events (currently being nearly equal to the number of real events). Our first prototype was developed last year and since then we have used it for extensive testing from which we have gained considerable insight. The original prototype was based on a long-period detector designed by Shearer (1994), but it has been heavily modified to address problems encountered in application to a data set from the Incorporated Research Institutes for Seismology (IRIS) broadband global network. Important modifications include capabilities for event masking and iterative event detection, continuous near-real time execution, improved Master Image creation, and individualized station pre-processing. All have been shown to improve bulletin quality. In some cases the system has detected marginal events which may not be detectable by traditional detection systems, but definitive conclusions cannot be made without direct comparisons. For this reason future work will focus on using the system to process GSETT3 data for comparison with current event detection systems at the IDC.
Date: August 1, 1996
Creator: Young, C.J.; Beiriger, J.I.; Harris, J.M.; Moore, S.G.; Trujillo, J.R.; Withers, M.M. et al.
Partner: UNT Libraries Government Documents Department

A comparison of the response of a captive carried store to both reverberant and progressive wave acoustic excitation

Description: Stores carried on high performance military aircraft are exposed to severe vibroacoustic environments which are caused by several different sources. Two methods available for simulating the acoustic portion of this environment in the laboratory are reverberant chambers and progressive wave tubes. The literature indicates that structures will respond differently to each of these acoustic sources as a function of frequency for the same Sound Pressure Level. Sandia National Laboratories participated in a test program that obtained acoustic data for a common store using both types of acoustic excitation. The purpose of this paper is to present the results from those tests in such a way so as to document the existence or absence of any significant differences in the coupling efficiencies for these acoustic sources.
Date: December 31, 1995
Creator: Cap, J.S.
Partner: UNT Libraries Government Documents Department

Proceedings of the workshop on neutron-induced gamma-ray physics at LANSCE/WNR

Description: The purpose of the workshop was to present the unique capabilities of LANSCE coupled with a large scale Compton suppressed Ge detector array and to help define a future experimental research program. This document contains the vuegraphs from the unclassified session. The vuegraphs were kindly provided by the invited speakers who came from both the university and the national laboratory communities. The talks focused on planned as well as potential experiments at LANSCE/WNR and their importance to the field.
Date: July 1, 1996
Creator: Strottman, D.D.
Partner: UNT Libraries Government Documents Department

Application of the GRI 1.2 methane oxidation model to methane and methanol oxidation in supercritical water

Description: The GRI 1.2 mechanism is used to predict the oxidation rates of methane and methanol by oxygen in supercritical water at 250 bar and temperatures ranging from 420--630 C. Using the Chemkin II computational package which assumes an ideal gas equation of state, the GRI model does very well in representing the available experimental results on methane over a wide temperature and concentration rate. However, the model may lack key CH{sub 3}O{sub 2} reactions needed for a complete description in the < 450 C region. The oxidation of methanol and formation of formaldehyde is not well represented by the GRI mechanism when left unchanged. If two important modifications are made to the reactivity of HO{sub 2}, good agreement with the methanol oxidation results is achieved. This paper illustrates that the carefully-assembled GRI 1.2 mechanism, although designed for conventional combustion conditions, can be successfully extended with very little modification to much lower temperature and extreme pressure conditions. The purpose of this study is to understand the operative chemical kinetics of supercritical water oxidation required for the more efficient application of this technology to treatment of hazardous wastes, obsolete munitions, rocket motors, and chemical warfare agents.
Date: May 1996
Creator: Rice, S. F.
Partner: UNT Libraries Government Documents Department

Non-proliferation issues for the disposition of fissile materials using reactor alternatives

Description: The Department of Energy (DOE) is analyzing long-term storage on options for excess weapons-usable fissile materials. A number of the disposition alternatives are being considered which involve the use of reactors. The various reactor alternatives are all very similar and include front-end processes that could convert plutonium to a usable form for fuel fabrication, a MOX fuel fab facility, reactors to bum the MOX fuel and ultimate disposal of spent fuel in some geologic repository. They include existing, partially completed, advanced or evolutionary light water reactors and Canadian deuterium uranium (CANDU) reactors. In addition to the differences in the type of reactors, other variants on these alternatives are being evaluated to include the location and number of the reactors, the location of the mixed oxide (MOX) fabrication facility, the ownership of the facilities (private or government) and the colocation and/or separation of these facilities. All of these alternatives and their variants must be evaluated with respect to non-proliferation resistance. Both domestic and international safeguards support are being provided to DOE`s Fissile Materials Disposition Program (FMDP) and includes such areas as physical protection, nuclear materials accountability and material containment and surveillance. This paper will focus on how the non-proliferation objective of reducing security risks and strengthening arms reduction will be accomplished and what some of the nonproliferation issues are for the reactor alternatives. Proliferation risk has been defined in terms of material form, physical environment, and the level of security and safeguards that is applied to the material. Metrics have been developed for each of these factors. The reactor alternatives will be evaluated with respect to these proliferation risk factors at each of the unit process locations in the alternative.
Date: February 1, 1996
Creator: Jaeger, C.D.; Duggan, R.A. & Tolk, K.M.
Partner: UNT Libraries Government Documents Department

Vicarious amination of nitroarenes with trimethylhydrazinium iodine

Description: This paper investigated the use of 1,1,1-trimethylhydrazinium iodide as a vicarious nucleophilic substitution reagent for introducing amino groups into nitroaromatic substrates. The substrates included nitroarenes, polynitrobenzenes, picramide, TNB,TNT, and dinitropyrazole; other nitroazoles are being studied.
Date: November 10, 1995
Creator: Pagoria, P.F.; Schmidt, R.D. & Mitchell, A.R.
Partner: UNT Libraries Government Documents Department

Effect of sulfur on the ductility of copper shaped-charge jets

Description: We have observed that a change in bulk sulfur (S) content imposed by doping has a marked effect on ductility of copper shaped-charge jets as measured by breakup times and length-to-diameter ratios of the particulated jet. Baseline material was Oxygen-Free-Electronic (ofe) copper with a S concentration of 3-4 ppM. Several liners were doped using a Cu sulfide powder pack method to increase the S level up to 9 ppM, while keeping other impurities and microstructure unchanged. Using flash x-ray radiographs to record the formation of jets, both the length-to-diameter ratios of the jet particles and breakup times were measured. Increasing the bulk S content of ofe Cu to 9 ppM, the breakup times decreased from 186 to 147 {mu}s, while the length-to- diameter ratios observed at 260 {mu}s decreased from 8:1 to 5:1. Since the solubility of S in Cu at the processing temperatures is extremely low, we conclude that the bulk rise in S content is due to S segregating to the grain boundaries. Thus, the decrease in ductility of liners doped with S appears directly related to the S content at the grain boundaries.
Date: July 1, 1996
Creator: Lassila, D.H.; Chan, D.K.; King, W.E.; Schwartz, A.J. & Baker, E.L.
Partner: UNT Libraries Government Documents Department

External Q studies for APT superconducting cavity couplers

Description: Coupling coefficients for the APT superconducting cavity couplers have been predicted using an improvement of the method previously developed for the French Trispal project. The authors here present the method and a proof of the formula used to compute the external Q. Measurements on a single-cell copper cold model exhibited a very good agreement against simulation. Then, they established that the original coupler design lead to an insufficient coupling in {beta} = 0.64 cavities. Different solutions were proposed to fix this problem, like combining impedance discontinuities in the line and an off-centered disc end tip. Finally, it was decided to increase the beam tube diameter though it has some influence on the cavity end-cell performance.
Date: December 31, 1998
Creator: Balleyguier, P.
Partner: UNT Libraries Government Documents Department

Safety issues in fabricating mixed oxide fuel using surplus weapons plutonium

Description: This paper presents an assessment of the safety issues and implications of fabricating mixed oxide (MOX) fuel using surplus weapons plutonium. The basis for this assessment is the research done at Los Alamos National Laboratory (LANL) in identifying and resolving the technical issues surrounding the production of PuO{sub 2} feed, removal of gallium from the PuO{sub 2} feed, the fabrication of test fuel, and the work done at the LANL plutonium processing facility. The use of plutonium in MOX fuel has been successfully demonstrated in Europe, where the experience has been almost exclusively with plutonium separated from commercial spent nuclear fuel. This experience in safely operating MOX fuel fabrication facilities directly applies to the fabrication and irradiation of MOX fuel made from surplus weapons plutonium. Consequently, this paper focuses on the technical difference between plutonium from surplus weapons, and light-water reactor recycled plutonium. Preliminary assessments and research lead to the conclusion that no new process or product safety concerns will arise from using surplus weapons plutonium in MOX fuel.
Date: July 1, 1998
Creator: Buksa, J.; Badwan, F.; Barr, M. & Motley, F.
Partner: UNT Libraries Government Documents Department

Defense programs industrial partnerships at Los Alamos National Laboratory

Description: The US Department of Energy`s Defense Programs face unprecedented challenges of stewardship for an aging nuclear stockpile, cessation of nuclear testing, reduced federal budgets, and a smaller manufacturing complex. Partnerships with industry are essential in developing technology, modernizing the manufacturing complex, and maintaining the safety and reliability of the nation`s nuclear capability. The past decade of federal support for industrial partnerships has promoted benefits to US industrial competitiveness. Recent shifts in government policy have re-emphasized the importance of industrial partnerships in accomplishing agency missions. Nevertheless, abundant opportunities exist for dual-benefit, mission-driven partnerships between the national laboratories and industry. Experience at Los Alamos National Laboratory with this transition is presented.
Date: October 1, 1996
Creator: Freese, K.B.
Partner: UNT Libraries Government Documents Department

Coupled explosive/structure computational techniques at Sandia National Laboratories

Description: Simulation of the effects of explosives on structures is a challenge because the explosive response can best be simulated using Eulerian computational techniques and structural behavior is best modeled using Lagrangian methods. Due to the different methodology of the two computational techniques and code architecture requirements, they are usually implemented in different computer programs. Explosive and structure modeling in two different codes make it difficult or next to impossible to do coupled explosive/structure interaction simulations. Sandia National Laboratories has developed two techniques for solving this problem. The first is called Smoothed Particle Hydrodynamics (SPH), a relatively new gridless method comparable to Eulerian, that is especially suited for treating liquids and gases such as those produced by an explosive. The SPH capability has been fully implemented into the transient dynamics finite element (Lagrangian) codes PRONTO-2D and -3D. A PRONTO-3D/SPH simulation of the effect of a blast on a protective-wall barrier is presented in this paper. The second technique employed at Sandia uses a new code called Zapotec that combines the 3-D Eulerian code CTH and the Lagrangian code PRONTO-3D with minimal changes to either code. CTH and PRONTO-3D are currently executing on the Sandia Terraflops machine (9000 Pentium Pro processors). Eulerian simulations with 100 million cells have been completed on the current configuration of the machine (4500 Pentium Pro processors). The CTH and PRONTO-3D combination will soon be executing in a coupled fashion on this machine.
Date: June 1, 1997
Creator: Preece, D.S.; Attaway, S.W. & Swegle, J.W.
Partner: UNT Libraries Government Documents Department

Polyplanar optic display

Description: The Polyplanar Optical Display (POD) is a unique display screen which can be used with any projection source. This display screen is 2 inches thick and has a matte black face which allows for high contrast images. The prototype being developed is a form, fit and functional replacement display for the B-52 aircraft which uses a monochrome ten-inch display. The new display uses a 100 milliwatt green solid state laser (532 nm) as its optical source. In order to produce real-time video, the laser light is being modulated by a Digital Light Processing (DLP{trademark}) chip manufactured by Texas Instruments, Inc. A variable astigmatic focusing system is used to produce a stigmatic image on the viewing face of the POD. In addition to the optical design, the authors discuss the electronic interfacing to the DLP{trademark} chip, the opto-mechanical design and viewing angle characteristics.
Date: July 1, 1997
Creator: Veligdan, J.; Biscardi, C.; Brewster, C.; DeSanto, L. & Beiser, L.
Partner: UNT Libraries Government Documents Department

Potential for use of all-MOX fuel in existing and evolutionary/advanced LWRs in the United States

Description: This paper reviews the application of US LWRs that are loaded with all-MOX fuel to dispose of excess weapon plutonium. The information presented is based on the DOE study results summarized in the 1993 DOE report, and the detailed reports submitted by reactor designers to DOE for that report. The reactor designs are the Westinghouse (Plutonium Disposition Reactor) PDR600, the GE Advanced BWR (ABWR), and ABB-Combustion Engineering System 80+. Analysis of published information in the nuclear community is the basis for an estimate of the capabilities of existing LWRs to switch from low-enriched uranium to all-MOX fuel. It is concluded to be feasible, if the conversion to PuO{sub 2} can be begun immediately, and lead test assemblies containing prototypical MOX fuel be made and irradiated. Russian VVERs should also be evaluated for Pu disposition.
Date: December 31, 1994
Creator: Walter, C.E.
Partner: UNT Libraries Government Documents Department

Screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil

Description: As part of the Rocky Mountain Arsenal (RMA) Remedial Investigation/Feasibility Study, RMA has contracted Argonne National Laboratory to investigate potential remedial alternatives for the cleanup of agent-contaminated soils. The chemical agents of concern include levinstein mustard, lewisite, sarin, and VX. This investigation has been initially divided into three phases: (1) a literature search to determine what, if any, previous studies have been conducted; (2) a technologies-screening critique of remedial technologies as alternatives to incineration; and (3) an investigation of promising alternatives on RMA soil at the laboratory and bench-scale levels. This paper summarizes the document produced as a result of the technologies screening. The purpose of the document was to determine the applicability of 25 technologies to remediation of agent-contaminated soil for a general site. Technologies were critiqued on the basis of applicability to soil type, applicability to the agents of concern at RMA, applicability to other types of contaminants, cost of the treatment, current status of the technology, and residuals produced.
Date: December 31, 1996
Creator: Shem, L.M.; Ballou, S.W. & Besmer, M.G.
Partner: UNT Libraries Government Documents Department

Chemometric Analysis of Two Dimensional Decay Data: Application to {sup 17}O NMR Relaxation Matrices

Description: The use of {sup 17}O NMR spectroscopy as a tool to investigate aging in polymer systems has recently been demonstrated. Because the natural abundance of {sup 17}O is extremely low (0.037%), the use of labeled {sup 17}O{sub 2} during the oxidation of polymers produces {sup 17}O NMR spectra whose signals arise entirely from the degradation species (i.e. signals from the bulk or unaged material are not observed). This selective isotopic labeling eliminates the impact of interference from the unaged material, cause (1) above. As discussed by Alam et al. spectral overlap between different degradation species as well as errors in quantification remains a major difficulty in {sup 17}O NMR spectroscopy. As a demonstration of the DECRA and CTBSA methods, relaxation matrices obtained from {sup 17}O NMR for model alcohol systems are evaluated. The benefits and limitations of these newly developed chemometric techniques are discussed.
Date: March 18, 1999
Creator: Alam, M.K. & Alam, T.M.
Partner: UNT Libraries Government Documents Department

Energetic charged particle beams for disablement of mines

Description: LLNL has an ongoing program of weapons disablement using energetic charged particle beams; this program combines theoretical and experimental expertise in accelerators, high-energy and nuclear physics, plasma physics and hydrodynamics to simulate/measure effects of electron and proton beams on weapons. This paper reviews work by LLNL, LANL and NSWC on detonating sensitive and insensitive high explosives and land mines using high-current electron beams. Computer simulations are given. 20--160 MeV electron beams incident on wet/dry soils are being studied, along with electron beam propagation in air. Compact high current, high energy accelerators are being developed for mine clearing. Countermine missions of interest are discussed. 25 refs., 9 figs.
Date: March 27, 1995
Creator: Wuest, C.R.
Partner: UNT Libraries Government Documents Department

Laser deflection of space objects -- An overview

Description: Lasers provide the two major attributes required for effective deflection of space objects: agility and efficiency. Lasers act instantaneously over long distances with little losses, but deliver energy at modest power levels. Material interceptors provide large impulses, but deliver only a fraction of the mass launched into space at low speeds. The two deflection concepts are compared, as are some important additional applications.
Date: April 1, 1997
Creator: Canavan, G. H.
Partner: UNT Libraries Government Documents Department

Spatio-spectral image analysis using classical and neural algorithms

Description: Remote imaging at high spatial resolution has a number of environmental, industrial, and military applications. Analysis of high-resolution multi-spectral images usually involves either spectral analysis of single pixels in a multi- or hyper-spectral image or spatial analysis of multi-pixels in a panchromatic or monochromatic image. Although insufficient for some pattern recognition applications individually, the combination of spatial and spectral analytical techniques may allow the identification of more complex signatures that might not otherwise be manifested in the individual spatial or spectral domains. We report on some preliminary investigation of unsupervised classification methodologies (using both ``classical`` and ``neural`` algorithms) to identify potentially revealing features in these images. We apply dimension-reduction preprocessing to the images, duster, and compare the clusterings obtained by different algorithms. Our classification results are analyzed both visually and with a suite of objective, quantitative measures.
Date: December 31, 1996
Creator: Roberts, S.; Gisler, G.R. & Theiler, J.
Partner: UNT Libraries Government Documents Department

Spectral imaging applications: Remote sensing, environmental monitoring, medicine, military operations, factory automation and manufacturing

Description: This paper reviews the activities at OKSI related to imaging spectroscopy presenting current and future applications of the technology. The authors discuss the development of several systems including hardware, signal processing, data classification algorithms and benchmarking techniques to determine algorithm performance. Signal processing for each application is tailored by incorporating the phenomenology appropriate to the process, into the algorithms. Pixel signatures are classified using techniques such as principal component analyses, generalized eigenvalue analysis and novel very fast neural network methods. The major hyperspectral imaging systems developed at OKSI include the Intelligent Missile Seeker (IMS) demonstration project for real-time target/decoy discrimination, and the Thermal InfraRed Imaging Spectrometer (TIRIS) for detection and tracking of toxic plumes and gases. In addition, systems for applications in medical photodiagnosis, manufacturing technology, and for crop monitoring are also under development.
Date: December 31, 1996
Creator: Gat, N.; Subramanian, S.; Barhen, J. & Toomarian, N.
Partner: UNT Libraries Government Documents Department

Range gated imaging experiments using gated intensifiers

Description: A variety of range gated imaging experiments using high-speed gated/shuttered proximity focused microchannel plate image intensifiers (MCPII) are reported. Range gated imaging experiments were conducted in water for detection of submerged mines in controlled turbidity tank test and in sea water for the Naval Coastal Sea Command/US Marine Corps. Field experiments have been conducted consisting of kilometer range imaging of resolution targets and military vehicles in atmosphere at Eglin Air Force Base for the US Air Force, and similar imaging experiments, but in smoke environment, at Redstone Arsenal for the US Army Aviation and Missile Command (AMCOM). Wavelength of the illuminating laser was 532 nm with pulse width ranging from 6 to 12 ns and comparable gate widths. These tests have shown depth resolution in the tens of centimeters range from time phasing reflected LADAR images with MCPII shutter opening.
Date: March 1, 1999
Creator: McDonald, T.E. Jr.; Yates, G.J.; Cverna, F.H.; Gallegos, R.A.; Jaramillo, S.A.; Numkena, D.M. et al.
Partner: UNT Libraries Government Documents Department

Quantum cryptography for secure free-space communications

Description: The secure distribution of the secret random bit sequences known as key material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is a new technique for secure key distribution with single-photon transmissions: Heisenberg`s uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). The authors have developed experimental quantum cryptography systems based on the transmission of non-orthogonal photon polarization states to generate shared key material over line-of-sight optical links. Key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. The authors have developed and tested a free-space quantum key distribution (QKD) system over an outdoor optical path of {approximately}1 km at Los Alamos National Laboratory under nighttime conditions. Results show that free-space QKD can provide secure real-time key distribution between parties who have a need to communicate secretly. Finally, they examine the feasibility of surface to satellite QKD.
Date: March 1, 1999
Creator: Hughes, R. J.; Buttler, W. T.; Kwiat, P. G.; Lamoreaux, S. K.; Luther, G. G.; Morgan, G. L. et al.
Partner: UNT Libraries Government Documents Department