The ARC compact RICH detector: Reconstruction and performance

Particle Identification (PID) is a key requirement for future Higgs factories such as FCC-ee, in particular for heavy-flavour physics and jet flavour tagging. The ARC (Array of RICH Cells) detector is a novel compact and modular RICH (Ring Imaging Cherenkov) concept designed to provide charged hadron separation over a momentum range 1 − 40 GeV/c . ARC combines gas and aerogel radiators within independent cells, each equipped with spherical mirrors and SiPM-based photodetectors. A detailed simulation and reconstruction framework has been developed, including inverse ray-tracing algorithms for Cherenkov angle reconstruction. Simulation studies demonstrate excellent photon yield and π / K separation performance across the target momentum range.