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The Innovative Confinement Concepts Workshop, ICC2002, provided a forum for presentations and exchange of ideas on the science and status of innovative concepts in the U.S. Fusion Energy Program. The workshop, held at the University of Maryland on January 22-24, 2002, included oral presentations addressing the important science and status of the concepts, posters focussed on details of the work, a skunkworks for novel ideas, and breakout sessions preparing for the July 2002 fusion energy Snowmass meeting. This report summarizes the oral presentations. A web site (https:// wormhole.ucllnl.org/ICC2002/) has been established with the abstracts and many of the presentations, both oral and poster, from the workshop.

Neutron production with laser-driven neutron sources was demonstrated. We outline the basics of laser-driven neutron sources, highlight some fundamental advantages, and quantitatively compare the neutron production at the TRIDENT laser sources with the well-established LANSCE pulsed neutron spallation source. Ongoing efforts by our team to continue development of these sources, in particular the LANSCE-ina-box instrument, are described. The promise of ultra-intense lasers as drivers for brilliant, compact, and highly efficient particle accelerators portends driving next-generation neutron sources, potentially replacing in some cases much larger conventional accelerators.

Magnetic nozzles have great potential for improving the efficiency and performance of coaxial plasma accelerators in applications such as space propulsion and advanced manufacturing. Proper design of magnetic field geometry can improve coaxial accelerator performance in three ways. First, applied field which intercepts the anode surface without directly connecting the two electrodes can minimize anode fall inefficiencies by improving electron conduction across the anode sheath and by opposing the Hall-induced starvation effect. Second, a properly designed magnetic geometry can provide a nozzling mechanism to permit the plasma to accelerate smoothly and efficiently from sub- to super-magnetosonic flow. Third, a magnetic nozzle provides control over the flow of plasma from the accelerator. For applications such as surface modification and etching, magnetic nozzles can maximize the treatable surface area and tailor the downstream plasma energy distribution. For thrust generation, proper design of a magnetic nozzle can enable efficient detachment of the plasma from the magnetic field.

This paper summarizes preliminary experimental and theoretical research that was directed toward the study of quasi-steady-state power flow in a large, unoptimized, multimegawatt coaxial plasma thruster. The paper addresses large coaxial thruster operation and includes evaluation and interpretation of the experimental results with a view to the development of efficient, steady-state, megawatt-class magnetoplasmadynamic (MPD) thrusters. Experimental studies utilized the Coaxial Thruster Experiment (CTX) facility at the Los Alamos National Laboratory. The unoptimized thruster, 1 m in length with inner and outer tungsten-coated electrode diameters of 0.37 and 0.56 m, respectively, was operated over a range of peak power levels (nominally 10-40 MW) in order to ascertain high-power performance scaling. In addition to pure self-field operation, an unoptimized applied magnetic field configuration, with adjustable flux densities, was used to form a rudimentary, annular magnetic nozzle. In this initial research, an accurate power balance was precluded due to the lack of spatial resolution of power deposition on the electrodes. However, the data, together with a calorimetric IR data reduction algorithm, did quantify energy flux deposition on electrode surfaces and provided a qualitative picture of global power flow and thruster performance. Highlights of this study include the observations that the measured longitudinal flow velocity of the propellant was in essential agreement with the prediction of self-field nozzle theory, achieving Alfvenic flow velocities of approximately equal to 10 to the fifth power m/s. Furthermore, radiative emission was a negligible power loss mechanism (

The design and first successful demonstration of an imploding solid liner with height to diameter ratio, radial convergence, and uniformity suitable for compressing a field reversed configuration is discussed. Radiographs indicated a very symmetric implosion with no instability growth, with ~13x radial compression of the inner liner surface prior to impacting a central measurement unit. The implosion kinetic energy was 1.5 megajoules, 34% of the capacitor stored energy of 4.4 megajoules. Index Terms--Capacitor bank, field reversed configuration, FRC, implosion, magnetized target fusion, megamp, MTF, radiography, solid liner.

Focuses on the research developments in plasma and fusion physics in the United States. Observation on space plasma physics by Active Magnetospheric Particle Tracer Explorers; Objectives of Tokamak Fusion Test Reactor; History of magnetic mirror.