Measurements of electron heat flow along a dc magnetic field in strong temperature gradients

Measurements of electron heat flow parallel to B are performed on a fully -ionized quiescent plasma column under conditions for which the electron-electron collisional mean free path, l/sub ee/, is not small relative to the electron temperature-gradient scale-length. Pulsed microwave heating at one location on the column and nonperturbing microwave resonator measurements of temperature at two locations on the column are used to create and to measure the heat flow. Results are compared with the predictions of a 1-D heat diffusion code that has a parameter, α, multiplying the Spitzer heat conductivity coefficient, and that also has provision for limiting the heat flux to q/sub L/ = βnkT √kt/m (where β is an adjustable parameter) in order to model the transition to larger values of (l/sub ee/T)dT/dx/