The reconstruction of particle trajectories makes it possible to distinguish between different types of charged particles. In high-energy physics, where trajectories are rather long, large size trackers must be used to achieve sufficient position resolution. However, in low-background experiments tracks are rather short and three dimensional trajectories could only be resolved in time-projection chambers so far. For detectors of large volume and therefore large drift distances, which are inevitable for low-background experiments, this technique is limited by diffusion of charge carriers. In this work we present a "proof-of-principle" experiment for a new method for the three dimensional tracking of charged particles by scintillation light: We used a setup consisting of a scintillator, mirrors, lenses and a novel imaging device (the hybrid photo detector) in order to image two projections of electron tracks through the scintillator. We took data at the T-24 beam-line at DESY with relativistic electrons with a kinetic energy of 5 GeV and from this data successfully reconstructed their three dimensional propagetion path in the scintillator. With our setup we achieved a position resolution of about 28 mum in the best case.
@article{arxiv.1404.3841,
title = {Three dimensional photograph of single electron tracks through a scintillator},
author = {Mykhaylo Filipenko and Timur Ishakov and Patrick Hufschmidt and Gisela Anton and Michael Campbell and Thomas Gleixner and Gerd Leuchs and Timo Tick and John Vallerga and Michael Wagenpfeil and Thilo Michel},
journal= {arXiv preprint arXiv:1404.3841},
year = {2015}
}