Electrostatic vortices associated with ion-temperature-gradient driven drift modes in electron-positron-ion plasmas

A set of nonlinear equations governing the dynamics of low-frequency electrostatic waves in the presence of equilibrium density, temperature, magnetic field and electrostatic potential gradients has been derived. In the linear limit, it is shown that nonzero equilibrium ion-temperature-gradient and the presence of positrons modify the basic drift modes. On the other hand, in the nonlinear case, it is shown that under certain conditions possible stationary solutions of the same set of nonlinear equations are reduced in the form of various types of vortex patterns. The results of the present investigation should be useful to understand the wave phenomena in laboratory and astrophysical e-p-i plasmas. (C) 2004 American Institute of Physics.