ABSTRACT
In chapter 2 we have seen that the interaction of an incoming charged particle with the detector material results in a number of energy transfers along the track that can lead to the ionisation of the detector material, creating pairs of negative (usually electrons) and positive (positive ions or holes) charge carriers. In chapter 3 we have seen how the movement of charges creates a current signal on a system of readout electrodes of an electronic particle detector. To create this signal, we have first, to separate the charges, and then, second, to keep them moving, as the induced current depends on their drift velocity in the external fields. To collect these charges for electrical readout, they need to be mobile, with a low probability for capture and recombination. Viable detector materials are therefore non-polar pure gases or liquids, or pure or lightly doped semiconductors.
