Electrostatic supersolitary waves: A challenging paradigm in nonlinear plasma science and beyond – State of the art and overview of recent results

A comprehensive overview is presented of recent theoretical advancements and observational manifestations of a relatively new type of electrostatic solitary wave (ESW), known as supersoliton or supersolitary wave (SSW). These nonlinear structures are characterized by a distorted pulse-shaped electrostatic potential excitations, deviating from the standard (“sech²”-like) form generally expected from solitonic pulses. In Space plasmas, in particular, e.g. in magnetospheric observations, SSWs may be associated with a characteristic wiggly bipolar electric field waveform. It has been shown that a three-component configuration is essential, as a minimum requirement for SSWs to occur in a plasma. Various spacecraft missions have recorded evidence of “non-conventional” electrostatic solitary waves (pulses) such as wiggly bipolar pulses, offset bipolar pulses, and monopolar pairs. This review article aims to present the current state of the art in this fascinating new theme, first outlining the basic framework for the modeling of such “exotic” ESWs and then putting forward a correlation between SSW structures with certain non-standard bipolar electric field forms observed in planetary magnetospheres.