KLOE

KLOE (or the K⁰_L LOng Experiment) was both an experiment studying Φ meson decays, and the particle detector used to conduct it. It was located in the DAΦNE collider at the INFN Frascati National Laboratory in Frascati, Italy. It ceased operation in 2006 and was replaced by the KLOE-2 detector, which began operation in 2014, and continues to operate to this day (2026).

For more information, see Wikipedia.