The pulsed-Townsend (PT) experiment is a well known swarm technique used to measure transport properties from a current in an external circuit, the analysis of which is based on the governing equation of continuity. In this paper, the Brambring representation (1964 Z. Phys. 179 532) of the equation of continuity often used to analyse the PT experiment, is shown to be fundamentally flawed when non-conservative processes are operative. The Brambring representation of the continuity equation is not derivable from Boltzmann’s equation and consequently transport properties defined within the framework are not clearly representable in terms of the phase-space distribution function. We present a re-analysis of the PT experiment in terms of the standard diffusion equation which has firm kinetic theory foundations, furnishing an expression for the current measured by the PT experiment in terms of the universal bulk transport coefficients (net ionisation rate, bulk drift velocity and bulk longitudinal diffusion coefficient). Furthermore, a relationship between the transport properties previously extracted from the PT experiment using the Brambring representation, and the universal bulk transport coefficients is presented. The validity of the relationship is tested for two gases Ar and SF₆, highlighting also estimates of the differences.

脉冲汤森 (PT) 实验是一种众所周知的群技术，用于测量外部电路中电流的传输特性，其分析基于连续性的控制方程。在本文中，Brambring 表示（1964 Z. Phys. 179常用于分析 PT 实验的连续性方程的第 532 条）被证明在非保守过程有效时存在根本性缺陷。连续性方程的 Brambring 表示不能从 Boltzmann 方程推导出来，因此框架内定义的输运性质不能根据相空间分布函数清楚地表示。我们根据标准扩散方程对 PT 实验进行了重新分析，该方程具有坚实的动力学理论基础，根据通用体积传输系数（净电离率、体积漂移）提供了由 PT 实验测量的电流的表达式速度和体纵向扩散系数）。此外，提出了先前使用 Brambring 表示从 PT 实验中提取的传输特性与通用体积传输系数之间的关系。对两种气体 Ar 和 SF 测试该关系的有效性₆、突出还估计的差异。