R802 at intersection I8, ISR

The photo shows the magnet (blue) of the spectrometer covering nearly the complete solid angle used by the CERN-Rome Collaboration to study negative particles at angles close to 0 deg with respect to one of the two colliding beams (Annual Report 1974, p. 108 and Photo Archive 7402246). Particles were identified by four threshold Cerenkov counters (on the left, bottom) and their trajectories were determined by twelve planes of MWPC (multiwire proportional chambers). The angular correlations between these particles and the over-all distribution of charged secondaries as observed in the hodoscope of R801 were also determined. On the centre a surveyor.