Remontage de la chambre à bulles de 2m

The 2 metre hydrogen bubble chamber opened out into its major component parts. It was reassembled to begin operation again after a long shutdown during which it had its first thorough cleaning since it came into operation in 1964. Important modifications which had been carried out were — shortening of the vacuum tank, where it was in the path of the beam, to allow final beam-line magnets to be installed closer to the chamber thus improving operation with low energy beams; repolishing of the windows and marking of new fiducial lines better adapted to HPD film measurement; installation of mirrors so that laser beams could be used to study optical distortion. The magnetic field was also remeasured with the chamber completely assembled.