A GEM based TPC for beam monitoring

TL;DR

This paper presents a GEM-based Time Projection Chamber with high spatial and angular resolution, capable of handling high beam rates and identifying various ion species, suitable for beam monitoring applications.

Contribution

Development of a 1 dm³ double-GEM TPC with advanced FPGA data acquisition enabling high-rate operation and precise particle tracking.

Findings

Spatial resolution of 50 μm and 280 μm achieved

Rate capability of about 100 kHz·mm⁻² demonstrated

Ion identification from helium to krypton possible

Abstract

In recent years Gas Electron Multipliers have proven to be reliable amplification stages at high beam rates, and can be used also in Time Projection Chambers. Our group developed a 1 dm$^3$ active volume double-GEM TPC, with spatial resolution of 50 $\mu m$ and 280 $\mu$m. Custom designed FPGA data acquisition system enables rate capability for about 100 kHz$\cdot$mm$^{-2}$, providing excellent track-by-track position and angular information, better than 0.1 mm and 1 mrad respectively. The wide dynamic range of the system enables identification from $^{4}$He up to $^{86}$Kr using ionization measurement. Two of these TPCs are planned to operate in tandem mode to filter off-time particles and to achieve a superior angular resolution.