Recent Performance Studies of the GEM-based TPC Readout (DESY Module)

TL;DR

This paper evaluates the performance of GEM-based TPC readout modules for the ILD at ILC, focusing on resolution, particle ID, and simulation insights, including new infrastructure like the LYCORIS telescope.

Contribution

It presents recent performance results of GEM-based TPC readout modules, introduces improved infrastructure, and provides simulation studies on high granularity effects.

Findings

GEM modules achieved target resolution levels.

Particle identification via dE/dx was demonstrated.

Simulation showed impact of granularity on resolution.

Abstract

For the International Large Detector (ILD) at the planned International Linear Collider (ILC) a Time Projection Chamber (TPC) is foreseen as the main tracking detector. To achieve the required point resolution, Micro-Pattern Gaseous Detectors (MPGD) will be used in the amplification stage. A readout module using a stack of three Gas Electron Multipliers (GEM) for gas amplification was developed at DESY and tested at the DESY II Test Beam Facility. After introducing the readout module and the infrastructure at the test beam facility, the performance related to single point and double-hit resolution of three of these modules is presented. This is followed by results on the particle identification capabilities of the system, using the specific energy loss dE/dx, and simulation studies, aimed to investigate and quantify the impact of high granularity on dE/dx resolution. In addition, a new and improved TPC field cage and the LYCORIS Large-Area Silicon-Strip Telescope for the test beam are described. The LYCORIS beam telescope is foreseen to provide a precise reference of the particle trajectory to validate the momentum resolution measured with a large TPC prototype. For this purpose, it is being installed and tested at the test beam facility within the so-called PCMAG (Persistent Current Magnet).