Subsonic and supersonic nucleus-acoustic solitary waves in thermally degenerate plasmas with heavy nucleus species

Abstract

A fully ionized multi-nucleus plasma system (containing thermally degenerate electron species, non-degenerate warm light nucleus species, and low dense stationary heavy nucleus species) is considered. The basic features of thermal and degenerate pressure driven small and arbitrary amplitude subsonic and supersonic nucleus-acoustic solitary waves in such a plasma system are studied by the pseudo-potential approach. The effects of stationary heavy nucleus, non-relativistically and ultrarelativistically electron degeneracies, and light nucleus temperature on small and arbitrary amplitude subsonic and supersonic nucleus-acoustic solitary waves are also examined. It is found that (i) the presence of stationary heavy nucleus species with Bolttzmann distributed electron species supports the existence of subsonic nucleus-acoustic solitary waves, and that the effects of electron degeneracies and light nucleus temperature reduce the possibility for the formation of these subsonic nucleus-acoustic solitary waves; (ii) the amplitude (width) of the subsonic nucleus-acoustic solitary waves increases (decreases) with the rise of the number density of heavy nucleus species; (iii) the amplitude of the supersonic nucleus-acoustic solitary waves in the situation of no-relativistically degenerate electron species is much smaller than that of ultra-relativistically degenerate electron species, but is much larger than that of isothermal electron species; (iv) their width in the situation of non-relativistically degenerate electron species is much wider than that of ultra-relativistically degenerate electron species; (v) their amplitude (width) decreases (increases) with the rise of the light nucleus temperature. The applications of the results in astrophysical, space, and laboratory plasma situations are briefly discussed.