1Indian Institute of Geomagnetism, Plot No. 5, Sector-18, New Panvel (W), Navi Mumbai 410218, India
2Radio Science Center for Space and Atmosphere (RASC), Kyoto University Gokasho, Uji, Kyoto 611-0011, Japan
Tóm tắt
Abstract. Electron-acoustic solitary waves are studied in an unmagnetized plasma consisting of non-thermally distributed electrons, fluid cold electrons and ions. The Sagdeev pseudo-potential technique is used to carry out the analysis. The presence of non-thermal electrons modifies the parametric region where electron acoustic solitons can exist. For parameters representative of auroral zone field lines, the electron acoustic solitons do not exist when either α > 0.225 or Tc/Th > 0.142, where α is the fractional non-thermal electron density, and Tc (Th) represents the temperature of cold (hot) electrons. Further, for these parameters, the simple model predicts negatively charged potential structures. Inclusion of an electron beam in the model may provide the positive potential solitary structures.
