Time projection chambers (TPCs) are widely used in nuclear and particle physics. They are particularly useful when measuring reaction products from heavy ion collisions. Most nuclear experiments at low energy are performed in a fixed target configuration, in which the unreacted beam will pass through the detection volume. As the beam intensity increases, the buildup of positive ions created from the ionization of the detector gas by the beam creates the main source of space charge, distorting the nominal electric field of the TPC. This has a profound effect on the accuracy of the measured momenta of the emitted particles. In this paper we will discuss the magnitude of the effects and construct an observable more appropriate for fixed target experiments to study the effects. We also will present an algorithm for correcting the space charge and some of the implications it has on the momentum determination.
@article{arxiv.1912.11045,
title = {Space Charge Effects in the S$\pi$RIT Time Projection Chamber},
author = {C. Y. Tsang and J. Estee and R. Wang and J. Barney and G. Jhang and W. G. Lynch and Z. Q. Zhang and G. Cerizza and T. Isobe and M. Kaneko and M. Kurata-Nishimura and J. W. Lee and T. Murakami and M. B. Tsang and S$π$RIT collaboration},
journal= {arXiv preprint arXiv:1912.11045},
year = {2020}
}