On the excitation of nonlinear ion acoustic waves in two-electron temperature plasmas of Multi-pole line cusp Plasma Device (MPD)

The Multi-pole line cusp Plasma Device (MPD) is a unique plasma device, in which the magnitude of the pole-cusp magnetic field can be varied. In addition, by varying the magnitude of the pole cusp magnetic field, the proportion of two-electron temperature components in filament produced plasmas confined by the multi-pole line cusp magnetic field of MPD can be varied. The nonlinear ion acoustic waves are excited and characterized by measuring the Mach number and amplitude-width relation. The nature of the solitons is further established by making two counter-propagating solitons interact with each other. Later, the effect of the two-temperature electron population on soliton amplitude and width is studied by varying the magnitude of the pole cusp-magnetic field. It has been observed that different proportions of two-electron-temperature significantly influence the propagation of IASs. The amplitude of the solitons has been found to be inversely proportional to the effective electron temperature (T_eff). The results of these studies and new experimental results will be discussed in detail, along with possible explanations.