Localized Structures and Anomalous dc Resistivity

Abstract

A new mechanism is presented for anomalous dc resistivity when the electron drift velocity is close to the electron thermal velocity and $T_e\gg T_i$. The turbulent plasma can break up into homogeneous essentially field-free regions (of width $\gtrsim 60{\lambda }_{\mathrm{D}e}$)) separated by ion density spikes ($\delta n_i\simeq n_1$) and potential jumps ($\frac{e\Delta \varphi }{\mathrm{kT}}>~1$) (double layers). dc resistivity results from the thermalization via an electron-electron two-stream instability of the energy gained by electrons accelerated over a potential jump. No runaway electrons are produced in this process.