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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.

One of the challenging problems in superconducting accelerator dipoles is their dynamic behavior under ramping magnetic field produced loads. Their behavior can be observed with hysteretic measurement of the energy flow in the magnet. This technique, first described in detail by M.N.Wilson, will determine changes in inductance, deflection of coils, dynamic losses, the superconducting cable's critical current vs. field and coupling curves, and iron shield saturation reproducibility. These measurements, when cross correlated with integral field, NMR and harmonic data yield a comprehensive characterization of the magnet. Data are presented for several magnets tested in the Magnet Test Facility of Fermilab. Measurements of inductance changes of a few percent and deflections of a few one-one thousandths of an inch are given. These data can now be routinely obtained on a production basis, therefore yielding a more complete characterization of the accelerator dipole's dynamic behavior.

Prototype superconducting quadrupoles with a 5 cm aperture and gradient of 16 kG/cm have been built and tested as candidate magnets for the final focus at SLC. The magnets are made from NbTi Tevatron style cable with 10 inner and 14 outer turns per quadrant. Quench performance and multipole data are presented. Design and data for a low current, high gradient quadrupole, similar in cross section but wound with a cable consisting of five insulated conductors are also discussed.