Experimental ion mobility measurements for the LCTPC Collaboration

Measuring the mobility of ions in gases is relevant in several areas, from physics to chemistry, e.g. in gaseous radiation detectors modelling and in the understanding of the pulse shape formation. One of these examples is the upcoming LCTPC (Linear Collider TPC) for the International Linear Collider (ILC), where a gating device will be installed at a certain distance from the gas amplification stage to neutralize the ions produced. Knowing the ion mobility will allow to calculate this distance and to ensure a high ion reduction while minimizing the thickness of the end plate. This work focuses on measurements of positive ion mobility for mixtures of interest for the LCTPC, more specifically Ar-CF$_4$-iC$_4$H$_{10}$ (95-3-2).