Parametric instabilities excited by an intense electromagnetic wave in a plasma is a fundamental topic relevant to many applications. These applications include laser fusion, heating of magnetically-confined plasmas, ionospheric modification, and even particle acceleration for high energy physics. In laser fusion, these instabilities have proven to play an essential role in the choice of laser wavelength. Characterization and control of the instabilities is an ongoing priority in laser plasma experiments. Recent progress and some important trends will be discussed. 8 figs.

This report describes models for multimegawatt, space power systems which Sandia's Advanced Power Systems Division has constructed to help evaluate space power systems for SDI's Space Power Office. Five system models and models for associated components are presented for both open (power system waste products are exhausted into space) and closed (no waste products) systems: open, burst mode, hydrogen cooled nuclear reactor -- turboalternator system; open, hydrogen-oxygen combustion turboalternator system; closed, nuclear reactor powered Brayton cycle system; closed, liquid metal Rankine cycle system; and closed, in-core, reactor therminonic system. The models estimate performance and mass for the components in each of these systems. 17 refs., 8 figs., 15 tabs.

A radiological performance assessment of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory was conducted to demonstrate compliance with appropriate radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the general public. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the general public via air, ground water, and food chain pathways. Projections of doses were made for both offsite receptors and individuals intruding onto the site after closure. In addition, uncertainty analyses were performed. Results of calculations made using nominal data indicate that the radiological doses will be below appropriate radiological criteria throughout operations and after closure of the facility. Recommendations were made for future performance assessment calculations.

This report describes Kesterson Reservoir related research activities carried out under a cooperative program between Lawrence Berkeley Laboratory and the Division of Agriculture and Natural Resources at the University of California during FY89. The primary objectives of these investigations are: Predict the extent, probability of the occurrence, and selenium concentrations in surface water of temporary wetland habitat at Kesterson; assess rates and direction of migration of the drainage water plume that seeped into the aquifer under Kesterson; monitor and predict changes in quantity and speciation of selenium in surface soils and vadose zone pore-waters; and develop a comprehensive strategy through soil, water, and vegetation management to safely dissipate the high concentrations of selenium accumulated in Kesterson soils. This report provides an up-date on progress made in each of these areas. Chapter 2 describes results of recent investigations of water table fluctuations and plume migration. Chapter 3 describes results of ongoing monitoring of soil water selenium concentrations and evaporative accumulation of selenium at the soil surface. Chapter 4 describes early results from the soil, water, and vegetation management field trials as well as supporting laboratory and theoretical studies. In Chapter 5, new analytical methods for selenium speciation are described and quality …

This report discusses the research being conducted at Lawrence Berkeley Laboratory's Accelerator and Fusion Research Division. The main topics covered are: heavy-ion fusion accelerator research; magnetic fusion energy; advanced light source; center for x-ray optics; exploratory studies; high-energy physics technology; and bevalac operations.