
Accession Number : ADA195840
Title : Marginal Stability of IonAcoustic Waves in a Weakly Collisional TwoTemperature Plasma without a Current.
Descriptive Note : Environmental research papers Jun 86Jun 87,
Corporate Author : AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA
Personal Author(s) : Basu, Bamandas ; Jasperse, John R
PDF Url : ADA195840
Report Date : 06 Aug 1987
Pagination or Media Count : 16
Abstract : This report presents two important results for a weakly collisional, currentfree, twotemperature electronion plasma: (1) that ei collisions have an undamping effect on ion acoustic waves, and (2) that, for appropriate values of the plasma parameters, ionacoustic waves become marginally stable. The results are based on the closed form solution for the dielectric function for the linearized BalescuLenardPoisson kinetic equations. The weakly collisional ordering is necessary to obtain an iterative solution for the collisional dielectric function, imposes two independent restrictions on the parameters that characterize the plasma. The linearized BalescuLenardPoisson equations are solved in the weakly collisional limit to show that ionacoustic waves in a currentfree plasma, which are Landaudamped in the absence of collisions, can become marginally stable due to the undamping effect of electronion (ei) collisions. For sq rt.(T sub e0/T sub i0) (5/16) sq rt.(m sub i/m sub e), the ei collisional undamping effect dominates the ii, ee, and ie collisional effects, and marginal stability occurs when the collisional undamping rate balances the electron and ion Landau damping rates. Keywords: Ion acoustic waves; Two temperature plasma. (JHD)
Descriptors : *PLASMAS(PHYSICS), *PARTICLE COLLISIONS, ACOUSTIC WAVES, BALANCES, COLLISIONS, DAMPING, DIELECTRIC PROPERTIES, ELECTRONS, IONS, ITERATIONS, LIMITATIONS, PARAMETERS, RATES, SOLUTIONS(GENERAL), STABILITY, TEMPERATURE
Subject Categories : Plasma Physics and Magnetohydrodynamics
Radiofrequency Wave Propagation
Distribution Statement : APPROVED FOR PUBLIC RELEASE