Development of a GEM-based time projection chamber prototype for low-energy rare-isotope beam experiments

In this study, we developed a time projection chamber (TPC) prototype with gas electron multipliers (GEM) to evaluate the basic performance of the GEM-based TPC for the rare-isotope beam experiments to be conducted at the RAON heavy-ion facility. The TPC prototype has a drift volume of 10×10×15 cm³, and we operated it in an Ar/CH₄ gas mixture (90/10). The TPC data acquisition system collected 256 pad signals in full-readout mode using cosmic-ray muons and α particles from an ²⁴¹Am source. The measured spatial resolutions on the pad plane and along the drift direction were 350μm and 250μm, respectively. We also discussed the tracking performance of the future active target TPC with a 20 AMeV ¹²Be beam.