Electrical conductivity of carbon plasma

The electrical conductivity of carbon plasmas is measured in the range of densities from about 0.6 solid density down to about 0.05 solid density, and reported for values of internal energy ranging from 2 to 22 kJ/gm. Plasmas are formed by rapid electrical discharge through thin graphite fibers immersed in a water bath. The pressure in the expanding plasma column is determined by use of a hydrodynamic model to describe the effect on the water surround. It is found that at constant internal energy per unit mass U, conductivity sigma varies with specific volume v as sigma=v(-alpha), where alpha is about 1 for U < 6 kJ/gm, and rises to about 1.5 for U=22 kJ/gm.