In 1972, the OMEGA spectrometer was commissioned in the West Area and more than a million collisions were recorded that very first year.

OMEGA was equipped with spark chambers - replaced at the end of the 1970s by electronic detectors - and a 15 000-tonne superconducting magnet. On this photo we can see the magnet's lower coil and, in the foreground, the support plate for the upper coil. No fewer than 48 experiments made use of this device, exploiting beams of various particles at various energies - from the PS at the beginning, and then from the highest energy beams of the SPS. OMEGA thus played a key role in many physics results and activities, notably the production of the J/psi particle, the study of particles carrying charm or beauty quarks, the study of «gluonia», and the CERN heavy ion programme. The OMEGA experiments ceased in 1996 when the facilities in the West Hall were shut down in preparation for the construction of the LHC.