Suppressed effective viscosity in the bulk intergalactic plasma

摘要: Transport properties, such as viscosity and thermal conduction, of the hot intergalactic plasma in clusters galaxies are largely unknown. Whereas for laboratory plasmas these characteristics derived from gas density temperature1, recipes can be fundamentally different plasma2 owing to a low rate particle collisions weak magnetic field3. In numerical simulations, unknowns often avoided by modelling hydrodynamic fluids4–6, even though local, non-hydrodynamic features observed contradict this assumption7–9. Using deep Chandra observations Coma Cluster10,11, we probe fluctuations medium down spatial scales where transport processes should prominently manifest themselves—provided that models12 with pure Coulomb collision rates indeed adequate. We do not find evidence processes, implying effective isotropic is orders magnitude smaller than naively expected. This indicates either an enhanced due scattering off microfluctuations caused instabilities2,13,14 or anisotropic respect local field15. also means models high Reynolds number appear more consistent observations. Our results demonstrate turbulence clusters16,17 giving rise branch astrophysics sharpen theoretical views on galactic plasmas. X-ray Cluster show instabilities field.