A numerical technique for investigating the behavior of many electron atoms in intense laser fields is presented. A description of the method is followed by results of an illustrative, application to helium for a number of wavelengths and intensities. A discussion of high order ionization dynamics for this system based on these calculations is provided. 10 refs.

Lawrence Livermore National Laboratory has a number of geothermal programs supported through two offices in the Department of Energy: the Office of Renewable Technologies, Geothermal Technologies Division, and the Office of Basic Energy Sciences, Division of Engineering, Mathematics and Geosciences. Within these programs, we are carrying out research in injection monitoring, optical instrumentation for geothermal wells, seismic imaging methods, geophysical and drilling investigations of young volcanic systems in California, and fundamental studies of the rock and mineral properties.

Medicine Lake Volcano, a broad shield volcano about 50km east of Mount Shasta in northern California, produced rhylotic eruptions as recently as 400 years ago. Because of this recent activity it is of considerable interest to producers of geothermal energy. In a joint project sponsored by the Geothermal Research Program of the USGS and the Division of Geothermal and Hydropower Division of the US-DOE, the USGS and LLNL conducted an active seismic experiment designed to explore the area beneath and around the caldera. The experiment of eight explosions detonated in a 50 km radius circle around the volcano recorded on a 11 x 15 km grid of 140 seismographs. The travel time data from the experiment have been inverted for structure and are presented elsewhere in this volume. In this paper we present the results of an inversion for 1/Q structure using t* data in a modified Aki inversion scheme. Although the data are noisy, we find that in general attenuative zones correlate with low velocity zones. In particular, we observe a high 1/Q zone roughly in the center of the caldera at 4 km depth in between two large recent dacite flows. This zone could represent the still molten …

In this paper the results of research on high temperature optical fiber sensors will be presented. We have shown that these sensors (optrodes) can be made to work in very high temperature water for long periods and that it is possible to measure pH using fluorescent inorganic ions doped into solid matrices. A high temperature pH optrode can be made using these techniques, however, more research is needed into the chemistry of the carrier matrices and fluorescent dopants.

The Department of Energy sponsors a 9-day training program for individual who are responsible for evaluating and planning safeguards systems and for preparing DOE Master and Security Agreements (MSSAs). These agreements between DOE headquarters and operations offices establish required levels of protection. The curriculum includes: (1) the nature of potential insider and outsider threats involving theft or diversion of special nuclear material, (2) use of computerized tools for evaluating the effectiveness of physical protection and material control and acoountability systems, and (3) methods for analyzing the benefits and costs of safeguards improvements and for setting priorities among proposed upgrades. The training program is varied and highly interactive. Presentations are intermixed with class discussions and ''hands-on'' analysis using computer tools. At the end of the program, participants demonstrate what they have learned in a two-and-one-half day ''field excercise,'' which is conducted on a facility scale-model. The training programs has been conducted six times and has been attended by representatives of all DOE facilities. Additional sessions are planned at four-month intervals. This paper describes the training program, use of the tools in preparing MSSAs for various DOE sites, and recent extensions and refinements of the evaluation tools.

A key issue in designing and evaluating nuclear safeguards systems is how to validate safeguards effectiveness against a spectrum of potential threats. Safeguards effectiveness is measured by a performance indicator such as the probability of defeating an adversary attempting a malevolent act. Effectiveness validation means a testing program that provides sufficient evidence that the performance indicator is at an acceptable level. Traditional statistical techniques are useful in designing a testing program when numerous independent system trials are possible. However, within the safeguards environment, many situations arise for which traditional statistical approaches may be neither feasible nor appropriate. Such situations can occur, for example, when there are obvious constraints on the number of possible tests due to operational impacts and testing costs. Furthermore, these tests are usually simulations (e.g., staged force-on-force exercises) rather than actual tests, and the system is often modified after each test. Under such circumstances, it is difficult to make and justify inferences about system performance by using traditional statistical techniques. In this paper, we discuss several alternative quantitative techniques for validating system effectiveness. The techniques include: (1) minimizing the number of required tests using sequential testing; (2) combining data from models inspections and exercises using Bayesian statistics …