A new air-cored D.C. magnet, for studies of superconductivity

“A [then] new air-cored DC magnet, for studies of superconductivity at CERN, together with its cooling-water manifolds and safety devices. Designed to be fed from existing electric generators, the coils consisted of 11 double pancakes, each with 12 independent parallel cooling circuits (see Report CERN 64-23 and also CERN COURIER, vol. 3, p. 157, December 1963). In the photo, the magnet can be seen on the left, in its steel frame, with the many hoses connecting it to the two water manifolds below. The magnet produced a field of 100 000 gauss* in a space 6 cm in diameter, using a current of about 6000 A. The resulting power dissipation was about 0.5 kW per cubic centimetre of coil. For protection, a relay switched off the generators if the flow of cooling water fell below a certain limit ; the tail cylinder in the centre of the picture contained water under pressure, to provide emergency cooling if such a situation were to occur while the generators were running down. In the picture also is Mario Grossi, who constructed much of the magnet.”