The Design, Construction, and Operation Update of the ISABELLE Ring Magnets

This report updates the various designs and prototypes tested since the last Conference. Included are the operational data of a subassembly of the old 200 × 200 GeV machine design as well as the latest larger prototype ring magnets with their strong points and shortcomings. The working line coil system design presently seems to be nearly completed, having gone through major revisions to increase its possible operational range. One of the major design goals of the magnet series, that of each unit being able to absorb their own energy, seems to be well in hand. This feature enables the magnet string to be protected without external intervention, i.e., without external energy dump or driving the magnet winding normal by an active external circuit. Simply stated, this means that the magnet's L/R time constants during quench are short enough to prevent thermal damage. There are two series of prototypes. The first type is the so called "Standard" which will become the ring magnet for ISABELLE. The second is that in which various characteristics and/or limits of various parameters are explored. Various parameters such as specific heat of the windings, increased metal packing fractions, and resistivity of turns (in the normal state) are bracketed. The 400 × 400 GeV version of ISABELLE1 requires acold aperture of 13.09 cm, quadrupole magnetic length of 1.6 m, and dipole length of 4.65 m at a peak dipole field of 5.0 T. Two machine size dipoles and one quadrupole are being presently tested.