Abstract:
A great deal of interest has been generated in the literature to study the newly found
structures known as supersolitons. Theoretical models are being developed to understand
these unusual electric field structures which have wiggle on their wings. The current
understanding of these structures require at least three-component plasma model. In this
work, ion-acoustic supersolitons are studied in three-component unmagnetized plasmas
comprising of Boltzmann electrons, nonthermal (Cairn’s distribution) electrons and fluid
cold ions. The supersoliton solutions are obtained for Mach number values beyond the
existence of double layers. The effect of nonthermality, cold electron density and cold to
hot electron temperature ratio is examined on ion-acoustic supersolitons. It is found that
presence of nonthermal electrons significantly affect the existence of the supersolitons.
The amplitude of the supersolitons decreases with the increase in the nonthermality for
the fixed value of Mach number. Our results show that electric field and electrostatic
potential of the supersolitons are more distorted which are obtained for Mach numbers
closer to the double layer solutions than the far away solutions. Due to the lack of observations
of these structures, either in space or laboratory plasmas, our theoretical model
predictions can not to be compared directly. However, it is worth investigating the data
on the electrostatic solitary structures observed by several satellites in the various region
of the Earth’s magnetosphere.
