First operation of BEBC

BEBC has been successfully operated from January to March 1973. The stainless steel piston was used in the magnetic field up to 2.6 T without visible degradation of the tracks. The pictures show good contrast and resolution and no visible distortion due to thermal turbulences. Reconstruction has not yet been done because only two views are available and no optical constants of the fish eyes were measured under working conditions. The dynamic load was quite high (25 KJ per pulse) and mainly due to excessive boiling around the piston seal. Actually the gap between the seal and the piston has been found to be several tenths of mm. Furthermore the pump which was supposed to run the heat exchanger near the piston seal below atmospheric pressure could not be put into service. (0 refs).