Complex sentence: The KLOE experiment was the first experiment performed by the DAϕNE collider, and it began in ernest when the detector began taking data in 2000 and ended when data collection stopped in 2006.
Split into simpler sentences: The KLOE experiment was the first experiment performed by the DAϕNE collider. It began in ernest when the detector began taking data in 2000 and ended when data collection stopped in 2006.