Ion acoustic solitary waves in electron-positron-ion plasmas with q -nonextensive electrons and high relativistic ions
- PDF / 393,864 Bytes
- 6 Pages / 595.276 x 790.866 pts Page_size
- 114 Downloads / 194 Views
ORIGINAL PAPER
Ion acoustic solitary waves in electron-positron-ion plasmas with q-nonextensive electrons and high relativistic ions H R Pakzad1* and K Javidan2 1
Department of Physics, Bojnourd Branch, Islamic Azad University, Bojnourd, Iran
2
Department of Physics, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
Received: 31 December 2012 / Accepted: 06 March 2013 / Published online: 26 March 2013
Abstract: Propagation of small amplitude ion acoustic solitary waves in plasmas containing q-nonextensive electrons, thermal positrons and high relativistic ions is addressed in this paper. Our results show that the Korteweg-de Vries equation describes the nonlinear waves in such plasmas. The amplitude and the width of the solitons are derived and the effects of relativistic ions and q-nonextensive distribution of electrons on these quantities are discussed. Keywords:
Relativistic plasma; Nonlinear; Ion acoustic soliton
PACS Nos.: 52.27.Ny; 52.35.Fp; 52.35.Sb; 52.25.Gj
1. Introduction In the last few years, there has been increasing attention on the different types of localized wave structures in the multispecies plasmas [1–4]. The ion acoustic soliton (IAS) is one of the most aspects of nonlinear phenomena in modern plasma physics research. Such nonlinear wave structures arise from the competition between nonlinearity, dispersion and dissipation behaviours. Investigation of such nonlinear structures is usually carried out by employing of perturbation techniques. In small amplitude approximation of the equations, one can derive some forms of nonlinear differential equations for one spatial dimension situations like Korteweg-de Vries (KdV), modified Korteweg-de Vries (m-KdV) or nonlinear Schrodinger equation, etc. Such equations have well known extended solutions, like solitary waves or solitons. A great number of authors have studied ion-acoustic solitary solutions using the reductive perturbation technique in different plasmas [5, 6]. In contrast to the usual plasmas consisting of electrons and positive ions, it has been observed that the nonlinear waves in plasmas which contain additional components such as positrons have different characters [7]. The behaviour of the electron-positronion plasmas helps us to find better knowledge about the early
universe which assumes to be a kind of plasma [8, 9], describing the active galactic nuclei [10], pulsar magnetospheres [11] and also the solar atmosphere [12]. Positrons can be used to probe particle transport in tokomaks, since they have sufficient lifetime. In this case, two-component electron-ion (e-i) plasmas become a three-component electron-ion-positron (e-i-p) medium [13]. During the last decade, e-p-i plasmas have attracted the attention of several authors [14–19]. It is known that the propagation of ion acoustic solitary wave is modified when the ion velocity approaches the speed of light. Relativistic plasmas occur in a variety of situations, such as, space–plasmas [20], laser– plasma interaction [21], plasma sheet boundary layer of the earth’s magn
Data Loading...
