Heat flux reduction by electromagnetic instabilities

Heat flux inhibition by microinstabilities in hot and dense plasmas is investigated. Because of the anisotropy induced by the temperature gradient, Weibel-like low frequency electromagnetic modes become unstable. The chaotic magnetic field thus generated effectively reduces the electron mean-free-path. Saturation of these instabilities is expected from mode-mode couplings. With the estimated saturation level, the mean-free-path is self-consistently found to be smaller than the typical gradient length L, thus keeping the heat flux below the free streaming value, with a reduction factor ε′= (c/Lωp)1/3.