The spatial resolution measurements on the small prototype of the Super Charm-Tau Factory drift chamber

Abstract

Budker Institute of Nuclear Physics is actively evolving the Super Charm-Tau Factory project. A drift chamber with a small hexagonal cell was proposed for this collider. For experimental measurements of a spatial resolution, a drift chamber small prototype consisting of seven cells has been developed. The experiments have been carried out in He/C3H8 (60/40) and He/C2H6 (50/50) gas mixtures at different gas gains using cosmic particles. For this purpose, a calibration procedure for R(t, α) has been developed and fine-tuned, taking into account small prototype features and an angular dependence of isochrones at the edge of the cells. As a result, the average spatial resolutions are less than 100μm for gas gains greater than 5⋅104.