Charge-Focusing Readout of Time Projection Chambers

TL;DR

This paper introduces a charge-focusing method for time projection chambers that reduces readout electronics costs by focusing drift charge onto a smaller area, enabling large-scale, cost-effective detectors for physics and security applications.

Contribution

The paper presents a novel static electric field focusing technique for TPCs, supported by simulations and initial experiments, to reduce readout area and costs while maintaining directional sensitivity.

Findings

Simulations demonstrate effective charge focusing with the proposed structure.

Initial experimental results align with simulation predictions.

Potential for large-scale, cost-efficient TPC detectors in various fields.

Abstract

Time projection chambers (TPCs) have found a wide range of applications in particle physics, nuclear physics, and homeland security. For TPCs with high-resolution readout, the readout electronics often dominate the price of the final detector. We have developed a novel method which could be used to build large-scale detectors while limiting the necessary readout area. By focusing the drift charge with static electric fields, we would allow a small area of electronics to be sensitive to particle detection for a much larger detector volume. The resulting cost reduction could be important in areas of research which demand large-scale detectors, including dark matter searches and detection of special nuclear material. We present simulations made using the software package Garfield of a focusing structure to be used with a prototype TPC with pixel readout. This design should enable significant focusing while retaining directional sensitivity to incoming particles. We also present first experimental results and compare them with simulation.