It is proposed that electromagnetic instabilities driven by temperature gradients can inhibit thermal conduction in intracluster gas. The suppression of the heat flux is due to rapid pitch-angle scattering by the self-excited waves. For typical parameters, the heat flux is inhibited by up to 3 orders of magnitude below the classical value in the outer parts of the inflow. This reduction may allow for the formation of a moderate homogeneous cooling flow, though not enough to allow the homogeneous flow to become supersonic. The transition to a multiphase cooling flow is also considered, and it is shown that this inhibition mechanism may reduce the thermal conductivity by the factor required for thermal instability to develop in the outer parts (R > 30 kpc) and for radiative cooling to quench evaporation of the cooled condensations in the central region of the flow.
- Cooling flows
- Intergalactic medium