A Statistical Study of Solitary Waves Using Polar Spacecraft Data

Solitary waves are discrete non-linear wave structures that have been observed in many regions of the magnetosphere. In this study we will present a statistical analysis of solitary waves. Results from Polar spacecraft electric field waveform capture bursts for more than a year of data will be presented, with emphasis on bursts in the auroral upward current region where ion beams are typically observed. This study will include analysis of the occurrence frequency of solitary waves in bursts and of the geographic distribution of solitary wave occurrences. The plasma conditions, including particle composition and distributions, will be examined for bursts containing solitary waves. The features of the solitary waves themselves, including propagation speed, potential amplitude, net potential, and structure size, will be examined both within given bursts and across the entire statistical sample of solitary waves. These observations will be compared to the results expected from theories on solitary waves and for the solitary waves in ion beam regions comparisons will also be made to our latest simulation results from ES2, a 2D3V electrostatic particle simulation.