By solving for the changes 〈Δν〉 and 〈ΔνΔν〉 for a particle, it is shown that there is no diffusion equation for non-resonant particles when the electric field wave is damping. By indirect means it is then shown for this case that the appropriate quasi-linear solution for ƒ1(к, ν, t) is proportional to ∂ƒ0(ν, 0)/∂ν rather than ∂ƒ(ν, t)/∂ν.

Resonance frequencies of a plane plasma condenser in crossed electric and magnetic fields are determined, using the two-component magnetic hydrodynamical equations. The perturbed plasma parameters (ion and electron densities and velocities and the electric field in the plasma), due to an external a.c. electric field are found. The calculated resonance is not exact since dissipative processes are neglected.

Waves, propagating transverse to the direction of the streaming of a plasma in the presence of a uniform external magnetic field, are unstable if the streaming exceeds a certain minimum value. The magnetic field reduces the growth rate of this instability, and also increases the value of the minimum streaming velocity, above which the system is unstable. The thermal motions in the plasma, however, tend to stabilize the system if the magnetic field is weak (i.e. , Ω being the electron cyclotron frequency, k the characteristic wave-number, and Vt the thermal velocity); but, in case of strong magnetic field (i.e. ), they increase the growth rate, provided (ωp being the electron plasma frequency).

The electron-energy distribution in a neon discharge is determined from the Boltzmann equation. Inelastic collisions with neutral atoms, as well as electron—electron Coulomb interactions, are included in the calculation. It is shown that, as predicted by Crescentini & Maroli (1968), the distribution is very close to the Druyvesteyn function when the electron density is very low (ne > 107 cm-3). The same conclusion, however, is not correct as the electron density increases to a higher value (ne > 1011 cm-3). In this case, the electron—electron Coulomb interactions play an important role in restoring the distribution toward a Maxwell jan function.

‘Effect of dissipation due to firehose instability on perturbation half-jet flow of a collisionless plasma’, by S. Mobioka and J. R. Spreitek. J. Plasma Physics, vol. 4, 1970, pp. 629–41

Equation (72) should be as follows: