Shock waves in charge-varying dusty plasmas and the effect of electromagnetic radiation

Abstract

Nonlinear electrostatic wave structures in dusty plasmas in the presence of electromagnetic radiation are investigated. The dust charge variation is assumed to be caused by microscopic electron and ion currents at the grains as well as photoelectric current of electrons. Calculations of electromagnetic radiation effects are performed for the case of solar radiation spectrum in the vicinity of the earth. The exact solutions of the nonlinear equations, describing variable-charge dust grains, Boltzmann electrons, and inertial ions, are obtained in the form of steady-state shocks. The conditions for their existence are found. The dissipation in such shock waves originates from the process of dust charging. The possibility of observation of shock waves related to the dust charging process in the presence of electromagnetic radiation in active rocket experiments which involve the release of some gaseous substance in near-earth space is discussed

Charged dust and shock phenomena in the Solar System

“…Thus for typical cometary nucleus size of about 1 km and rather dense dusty coma (n d >10 6 cm −3 ) the bow shock formed as a result of the interaction of the solar wind with the coma is expected to be related to the anomalous dissipation due to the dust particle charging. The bow shock is similar, by its origin, to the shocks observed by Luo et al (1999) and Nakamura et al (1999) and those predicted theoretically by Popel et al ( , 2000. 226 S. I. Popel and A.…”

“…The idea of application of such experiments to the problem of formation of shocks related to dust charging was forwarded in the papers (Popel and Tsytovich, 1999;Popel et al, 2000). The optimum altitudes for the experiments allowing us to observe the dust ion acoustic shocks are 500-600 km.…”

“…(1) and (2), the continuity equation for the solar wind protons is included, the cometary coma ions are described by the continuity and momentum transfer equations, the electron density is taken to be Boltzmann with constant T e , and the Poisson's equation is used. This model is a generalization of the model applied for the study of shock-like structures in charge-varying dusty plasmas in the presence of the electromagnetic radiation (Popel et al, 2000) but developed with taking into account the two sorts of ions. In Fig.…”

“…where q d =Z d e is the dust particle charge; I e , I SW i , I c i are the microscopic grain currents (originating from the potential difference between the plasma and the grain surface) of electrons, solar wind ions, and cometary coma ions, respectively; I ph is the photoelectric current of electrons emitted from the dust grain surface due to the presence of external electromagnetic radiation: for their explicit expressions see, e.g., (Popel et al, 2000); -e is the electron charge.…”

Effects of dust charge fluctuations and deviations from isothermality of electrons on nonlinear dust ion-acoustic waves

“…It is obvious that this type of shock solution arises due to the combined effects of nonlinear term (containing α 2 ) which arises due to the trapped electrons, and the dissipative term (containing α 4 ) which arises due to the dust charge fluctuation. We note that the DIA shock structures studied by Popel et al (2000) do not follow our dusty plasma model and mathematical procedures. However, some of the basic features of the shock structures predicted here are similar to those studied there.…”