The possibility of using a simple pulse mode parallel plate gas ionization chamber, without Frisch grid, both for energy estimation and Z-identification of moderate energy light heavy ions

Abstract

This work explores theoretically the possibility of using a simple pulse mode parallel plate gas ionization chamber, having no Frisch grid, both for energy estimation and Z-identification of moderate energy light heavy ions. A mathematical expression for the energy of a heavy ion that enters into the ionization chamber through the cathode window and gets stopped in the sensitive volume is derived. An expression for a quantity similar to the range of the heavy ion is also derived. The plot of energy against this quantity is expected to give an opportunity to use a simple pulse mode parallel plate gas ionization chamber, without Frisch grid, as a light heavy Z-identifier. This work is based on the measurement of the electron collection pulse height and two other heights that the electron collection pulse reaches at two pre-calculated instants of time during the pulse rise time. A 'preset pulse clipper', the basic principle of which was proposed in a previous paper, may be used to measure the heights. Measuring heights - without using the 'preset pulse clipper' - by means of digital sampling and software based processing techniques may be possible if it be possible to determine the start time of the digitized pulse. One possible method for determining the start time of the digitized pulse is evaluated. The simulated plots, which represent the expected identification capability of this method, are made considering all the phenomena relevantly associated from physical point of view.