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Charge collection efficiency (CCE) generated in a 6H-SiC [p.sup.+]n diode by impact of heavy ions was evaluated by the transient ion beam induced current (TIBIC) technique. Numerical analysis by using technology computer aided design (TCAD) concludes that the Auger recombination process reduces CCE. Comparing experimentally measured CCEs with calculated ones revealed that the ambipolar Auger coefficient of about 3 x [10.sup.-29][cm.sup.6]/s. Index Terms--6H-SiC diode, auger recombination, CCE, PHD, TCAD, TIBIC system.

Single Event Transient (SET) current is one of the most interesting issues for understanding and predicting Single Event Effects (SEEs) in real space environments. Since space radiation consists of high energy heavy ions, estimation of the energy dependence of SET currents is required. In order to estimate this effect, we have developed the Transient Ion Beam Induced Current (TIBIC) system combined with collimated high energy ion beams accelerated by AVF Cyclotron. We have demonstrated the function of TIBIC developed here. Using the newly developed TIBIC system and the Technology Computer Aided Design (TCAD) simulator, the influence of ion energy on SET currents is estimated. Index Terms--Collimated beam, single event transient (SET) current, transient ion beam induced current (TIBIC).

A two-turn D-shaped test coil with a height of 2.0 m and a width of 1.8 m is fabricated by a react-and-wind method by using a 20 kA Nb3Al cable-in-conduit (CIC) conductor. The total strain of the D-shaped test coil is about 0.57 percent, the same as the triplex-CIC sample fabricated by a W&R method, indicating that bending did not influence the I(sub c).

Tests of the International Thermonuclear Experimental Reactor (ITER) Toroidal Field (TF) Insert and Central Solenoid Model Coil (CSMC) are evaluated.

Performance of the NbAl Insert and the International Thermonuclear Experimental Reactor (ITER) Central Solenoid Model Coil (CSMC) are discussed.

The International Thermonuclear Experimental Reactor's (ITER) Central Solenoid Model Coil (CSMC) project is described and discussed. All of the project's goals were successfully achieved.

Distributions on the surface of zero-field-cooled Bi2223 monocore tapes were measured using a micro Hall-sensor.

Magnetic field distribution measurements in a melt-textured YBa2Cu3O7-x superconductor with an artificial grain boundary are presented.

Test results of the 460-kA Nb3Sn conductor joint for the ITER model coils are presented.

The completion of the outer module fabrication for the ITER CS model coil is discussed and the future connection to the inner module coil is considered.

A study was conducted to clarify the impact of mechanical load under rolling on microstructures and transport current paths in silver-sheathed Bi2223 monocore tapes, which are promising for power engineering applications. Analyses on trapped-magnetic fields in a remanent state by a scanning Hall sensor in combination with metallurgical studies reveal the evolution in transport current paths in superconductor core and the critical current distributions therein.

The fabrication of the International Thermonuclear Experimental Reactor's (ITER) Central Solenoid (CS) Model Coil - Outer Module is nearly complete save for the epoxy impregnation of concrete whole layers. The international project, undertaken to justify the CS design for the ITER, has had all of its wound and heat treated layers symmetrically installed with the insulation on the same axis. The layer-to-layer butt joint has also been installed.

The effect of a heat spreader on the life of the solder joints for underfill-encapsulated, flip-chip packages is investigated through stress analyses and thermal cycling tests. An underfill with suitable mechanical properties is found to be able to prolong the fatigue life of the solder joints even in a package with a heat spreader and an alumina substrate. The delamination of the underfill from the chip is revealed as another critical failure mode for which the shape of the underfill fillet has a large effect.

Japan Atomic Energy Research Institute is constructing the International Thermonuclear Experimental Reactor common test facility for the Central Solenoid Model Coil which is around 180 tons, a forced-flow cooled magnet with the maximum pulsed operation of 2 T/s and generates the rated magnetic field of 13 T at 48 kA with stored energy of 668 MJ. The test facility consists of a coil vacuum chamber, a cryogenic system with the 5-kW refrigerator and 500-g/s cryogenic pump, two pairs of 50-kA current leads, two DC power supplies (50kA and 60kA) and two JT-60 pulsed power supplies (50 kA, [+ or -]4.5 kV and [+ or -]40 kA, [+ or -]1.5 kV). The facility will be demonstrating the refrigeration and operation of a fusion pulsed magnet and the design and construction will accumulate experience towards the construction of ITER.

The [Nb.sub.3]Sn cable is being fabricated for the Central Solenoid (CS) Model Coil under the ITER Engineering-Design Activity. The cable consists of about 1000 strands whose diameter is 0.81 mm. The design current is 48 kA at a magnetic field of 13T. The 0.6-GJ CS model coil is operated in a pulse mode (0.5T/s). The first trial fabrication of a 100-m dummy cable and a 20-m superconducting cable was completed successfully. The second trial fabrication of a 1000-m dummy cable was performed to establish the stable manufacturing procedure in January, 1995. We measured the AC losses of the full-sized conductor and could determine the cable coupling time constant. We analyzed the heat generation of the CS model coil and calculated the temperature rise of the cable for the model coil.

The effect of cyclic pulsed operation on the coil performance was studied from the electrical and mechanical points of view in the second experiment of the [Nb.sub.3]Sn Demo Poloidal Coil (DPC-EX). Current sharing temperatures, ac losses, displacements, and strains were measured before and after cyclic pulsed operation, which consisted of about 350 cycles. No degradation of the electrical and mechanical performance of the DPC-EX was observed in the range of these cycles.

Japan Atomic Energy Research Institute (JAERI) has been developing 13-T, 40-kA conductors for the ITER Central Solenoid Scalable Model Coil. The conductors are composed of high performance [(NbTi).sub.3]Sn strands and titanium conduit. In this development work, 15-km length strand fabrication from a 100-kg billet, chrome plating, cabling of 675 or 768 strands, jacketing of titanium conduit, and so on were conducted by two mass production lines. In this paper, several test results are reported such as critical current measurements of full-scale conductors and AC loss measurements of sub-scale conductors.

The characterization of the Toroidal Model Pancake (TMP) is presented. The TMP is a superconducting coil constructed by the Japan Atomic Energy Research Institute for fusion reactor studies. Built of hollow cooling monolithic superconductors, it begun testing in Aug 1992. Its performance is described along with cooldown, pressure drop, stability and mechanical issues.

The Demo Poloidal Coil-TJ is a superconducting coil for a superconducting fusion magnet. Developed by Toshiba and the Japan Atomic Energy Research Institute, the force-cooled coil is designed for high-magnetic-field and high-current-density operation and is built of Nb3Sn cable-in-conduit conductors. It is electromagnetically and mechanically stable, as borne out by quenching tests and measurements of its critical current and current sharing temperature.

Micrometer thick [Bi.sub.3][Fe.sub.5][O.sub.12] (BIG)(001) films were grown onto [Gd.sub.3][(ScGa).sub.5][O.sub.12](001) single crystals by the pulsed laser deposition technique. The films are of epitaxial quality with a lattice constant of 1.263 nm. Narrow x-ray rocking curves (full width at half maximum: 0.06 deg) and narrow ferromagnetic resonance lines (widths of 25 Oe) indicate good crystalline quality and magnetic performance. The films possess in-plane magnetization, Faraday rotation as high as -7.8 deg/[micro]m at 630 nm wavelength, and the magnetization M-H curves are linear in the field range from -1.6 kOe to -1.6 kOe. The magneto-optical (MO) properties are almost temperature independent between 5 K and 200 K. This enables the use of thin BIG films as visualizers of magnetic fluxes in high-[T.sub.c] superconductors. Magnetic fluxes have been visualized in [YBa.sub.2][Cu.sub.3][O.sub.7-x] (YBCO) ceramics with an artificial grain boundary. The sensitivity expressed as Faraday rotation angle (per film thickness) per magnetic field unit was found to be 4.9 deg/(kOe [multiplied by] [micro]m) in a 730 nm thick BIG film. Index Terms--Epitaxial [Bi.sub.3][Fe.sub.5][O.sub.12] film, Faraday effect, pulsed laser deposition, visualizer.