Self-similar electron distribution, inverse bremsstrahlung, and heat flux inhibition in high-Z nonuniform plasmas

The self-similar distribution of electrons is found for a nonuniform underdense plasma that is heated by an intensive laser field. The distribution function is flat-topped for the low-energy electrons. And in the high-energy region, it has a well-pronounced high-energy tail. It is also found how the electron heat flux and the absorption coefficient depend upon both the ratios of electron mean-free path to the inhomogeneity scale of effective temperature and of the oscillation velocity to the thermal velocity. The actual shapes of electron energy distribution, the heat flux limitation, and the electromagnetic radiation absorption rate are given, both for a currentless plasma and for a plasma with a finite electric current.