Solitary waves and double layers in an ultra-relativistic degenerate dusty electron-positron-ion plasma

Abstract

A rigorous theoretical investigation has been made on the formation of the nonlinear structures (viz., solitary waves, double layers) in a dusty electron-positron-ion plasma (containing inertialess degenerate electrons and positrons, cold, mobile, inertial ions, and negatively charged stationary dust). The pseudo potential method has been employed in this theoretical investigation. The basic features of the solitary waves and double layers, which are associated with positive ion dynamics and pressures of degenerate electrons and positrons, are identified. The co-existence of positive and negative solitary waves, and existence of either positive or negative double layers have been theoretically observed for certain range of different plasma parameters. The implications of our results in astrophysical compact objects have been briefly discussed.

Plasma and trap-based techniques for science with positrons

“…Linear aspects of the system have been considered in several studies (Iwamoto, 1993;Stewart and Laing, 1992;Zank and Greaves, 1995). Nonlinear processes have been a particularly rich area including such aspects as solitary waves (Dubinov et al, 2006;El-Shamy et al, 2010;Ghosh et al, 2012;Gordienko and Dubinov, 2008;Roy et al, 2012;Sabry, 2009), solitons (Cattaert and Kourakis, 2005;Sabry et al, 2009;Zank and Greaves, 1995), double layers (Alterkop et al, 2007;Mishra et al, 2007), collisionless reconnection processes (Bessho and Bhattacharjee, 2005;Hosseinpour and Vekstein, 2008) electrostatic and electromagnetic wave phenomena (El-Taibany and Mamun, 2012;Ghosh et al, 2012;Gordienko and Dubinov, 2007;Kourakis et al, 2007;Mushtaq and Khan, 2008), and vortices (Shukla et al, 2003).…”

Modified Ion-Acoustic Shock Waves and Double Layers in a Degenerate Electron-Positron-Ion Plasma in Presence of Heavy Negative Ions

“…Equation (38) is like Gardner equation with additional dissipative term. There are two solutions of this (38); one is for shock wave and another is for double layer from where we can easily make difference and have a clear view between the shock wave and double layer.…”

“…We note that the differential equation (38) has different kinds of solution depending on different initial boundary conditions used for the system under consideration. Since we are interested here in looking for shock and double layer solutions, we use appropriate boundary conditions for obtaining such types of solution.…”

“…More recently, a large number of authors [27,[38][39][40][41][42][43] studied the basic properties of solitary, and shock waves by deriving the Korteweg-de Vries (K-dV), modified K-dV (comes from higher order of K-dV equation), Gardner (comes from higher term of modified K-dV equation), and Burgers equation for planar and nonplanar cases in considering different types of effects [34,35,44,45]. But the interesting point is to note that the Burgers equation for nonplanar case is called modified Burgers equation [46][47][48].…”

Modeling of modified ion-acoustic shock waves in a relativistic electron degenerate multi-ion plasma for higher order nonlinearity

“…are examples where relativistic degenerate plasmas are dominant and interesting new phenomena are investigated by several nonlinear effects in such plasmas. In case of such a compact object, the degenerate electron number density is so high (in white dwarfs it can be of the order of 10 30 cm −3 , even more) (El-Taibany and Mamun 2012; Roy et al 2012;Hossen et al 2014h), such that their cores are composed of strongly coupled non-degenerate ion lattices immersed in degenerate electron fluids that follow the Fermi-Dirac distribution function (Glenzer and Redmer 2009). For such interstellar compact objects the equation of state for degenerate electrons are mathematically explained by Chandrasekhar (1935).…”