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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.

Time-dependent functions giving distributions over instantaneous values of electron momenta and energies in a laser Seld are derived. These distribution functions are found for arbitrary values of the ratio of the electron thermal velocity to the electron oscillation velocity. They are necessary in studies of laser-radiation interaction with plasma, laser-plasma x-ray lasers, etc.

A nanoscale chaotic relief structure appears as a result of subthreshold single shot femtosecond laser ablation of gold films in the regimes of fabrication of microbumps and nanospikes, but only for a relatively thick film. The observed nanoablation tendency versus film thickness makes it possible to suppose the existence of a sub surface temperature maximum in thicker gold films and its absence within thinner film, which results from competing evaporative cooling and electronic heat conduction, as demonstrated by numerical simulations of the thermal dynamics.