Field-reversed configuration
A field-reversed configuration (FRC) is a device developed for magnetic confinement fusion research that confines a plasma on closed magnetic field lines without a central penetration.
The FRC was first observed in laboratories in the late 1950s during theta pinch experiments with a reversed background magnetic field. The first studies of the effect started at the United States Naval Research Laboratory (NRL) in the 1960s. Considerable data has been collected since then, with over 600 published papers. Almost all research was conducted during Project Sherwood at Los Alamos National Laboratory (LANL) from 1975 to 1990, and during 18 years at the Redmond Plasma Physics Laboratory of the University of Washington, with the large s experiment (LSX). More recently some research has been done at the Air Force Research Laboratory (AFRL), the Fusion Technology Institute (FTI) of the University of Wisconsin-Madison and the University of California, Irvine. Some private companies now theoretically and experimentally study FRCs in order to use this configuration in future fusion power plants they try to build, like General Fusion, Tri-Alpha Energy, Inc., and Helion Energy.
The FRC is also considered for deep space exploration, not only as a possible nuclear energy source, but as means of accelerating a propellant to very high levels of specific impulse (Isp) for electrically powered spaceships and fusion rockets, with interest expressed by NASA and the media.
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