Study of Antiproton Reactions in LArTPC with J-PARC T98 data and Simulation

In the search and measurement for cosmic antiparticles, as one of the benchmarks for the GRAMS experiment, understanding of antiproton reactions in a liquid argon TPC with high-statistics is a vital research milestone. The identification of particles and antiparticles relies on the annihilation of antiprotons, which stop in liquid argon and interact with argon nuclei, producing multiple hadrons. However, experimental validation of this process remains insufficient. To address this, in February 2025, a 30 cm³ liquid argon TPC detector was installed at the J-PARC K1.8BR beamline (J-PARC T98), and large-statistics datasets were successfully collected, including antiprotons with a momentum of 700 MeV/c, as well as protons and deuterons. This poster presents the results of data analysis from the experiment, insights gained from simulations, and the evaluation of particle-antiparticle identification capability.