A new method to calculate the electron swarm parameters by employing a Fourier transformed Boltzmann equation is presented in which the swarm parameters are derived from the dispersion relation of the equation. The method is applied to krypton and sulphur hexafluoride(SF6) gases. The results are compared with those obtained by conventional methods and the practical features of the present method are discussed. It is shown that the method is a reliable means to deduce the electron swarm parameters.

An accurate and efficient method for solving the Boltzmann equation for electron swarms in gases is proposed. The method utilises the conventional two-term expansion and a Galerkin technique for solution of the Boltzmann equations in an amalgamated form; the first two terms of the Legendre polynomial expansion of the electron energy distribution are obtained by the two-term method while the third and higher-order terms are deduced by the Galerkin method. Although a relaxation procedure has to be used for connecting the solutions and making them self-consistent by the two methods, the present amalgamated method can reduce the size of the matrix for the Galerkin technique, which may serve to make the computational time shorter. The present technique is applied to deduce the electron energy distribution and swarm parameters in methane gas, and good agreement with those calculated by Monte Carlo simulation is obtained. This shows the validity of the proposed method. The computational time of the present method is estimated to be roughly of the order of the geometric mean of those by the two-term expansion and Monte Carlo methods.

An accurate and efficient method for solving the Boltzmann equation is presented. Using a multi-term expansion technique, the time-of-flight (TOF) electron swarm parameters (such as the centre-of-mass drift velocity Wr, the longitudinal DL and transverse DT diffusion coefficients) can be evaluated. The method utilizes an amalgamation of the conventional two-term expansion and the Galerkin method. The first two terms of the Legendre polynomial expansion of the electron energy distribution are obtained by the two-term method, while the third-order and higher-order terms are deduced by the Galerkin method. The present technique is applied to determine the electron energy distribution using Fourier components to solve the Boltzmann equation and TOF swarm parameters in methane gas. Good agreement with Monte Carlo simulation is obtained and the method is also applied to a previously described model gas.

An analysis of the swarm parameters defined by the arrival time spectra (ATS) of electron swarms in gases, using a multi-term expansion technique of calculation for solving the Boltzmann equation, is presented. The ATS method is important since it enables one to calculate directly important swarm parameters such as the ionization coefficient and the mean arrival-time drift-velocity. This method is applied to methane gas, which has extremely large inelastic electron collision cross-sections, not only in the high electron-energy region but also in the low electron-energy region, and the ATS swarm parameters and energy distributions are calculated by means of a multi-term technique for the first time. The multi-term technique utilizes an amalgamated procedure of the conventional two-term expansion and the Galerkin method. The results by this technique are compared with those by a Monte Carlo simulation, to show good agreement for both relatively high and low E/p0 conditions.

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