High Field Pulsed Magnets for a Bubble Chamber Beam
To facilitate the production of hyperon-enriched beams for bubble chamber experiments, a range of pulsed magnets has been developed, featuring 20-40 cm-long bending magnets with peak fields up to 13T, and 30-60 cm-long quadrupoles having gradients as high as 50OT/m; ape rtu res a re typically 2-6 cms. Such parameters lend themselves to beam lines capable of kinematic analysis and focusing in very short distances, with consequent minimised decay losses. All magnets are air-cored and water-cooled, with goemetries tailored to suit particular experimental requirements. Of singular importance are the measures taken to distribute in-pulse loads and minimise fatigue so that lifetimes may be stretched to at least 200,000 shots. Special attention is paid to the cooling of otherwise-limiting components of clamping assemblies, permitting the pulsed beamline to operate at machine rates of 25 ppm, and even to double-pulse if necessary.