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A thin superconducting magnet being developed for long-duration balloon flights in Antarctica is discussed. BESS-Polar is being prepared as part of the Balloon-borne Experiment with a Superconducting Solenoid Magnet Spectrometer, or BESS, which has been carried out as a US-Japan cooperative scientific effort since 1993, investigating cosmic rays.

The Central Solenoid for the CERN Large Hadron Collider's (LHC) ATLAS detector was completed and performance was successfully carried out in Japan, and the solenoid has arrived at CERN. Its fabrication and mechanical performance are discussed.

The ATLAS experiment's central solenoid magnet was developed in a cooperative effort involving Conseil Europeenne pour Recherches Nucleaires, now known as the European Laboratory for Particle Physics, Geneva, Switzerland; and Koo Energy Ken, the High Energy Research Accelerator Organization in Tsukuba, Japan. Two methods for quench protection are discussed.

The ATLAS detector is one of two main detectors in the Large Hadron Collider project at the European Organization for Nuclear Research (CERN), and a thin superconducting solenoid is being developed for installation in the detector. A long chimney in the gap between the outer detectors and toroidal magnets is where a control dewar at the top of the detector is connected with a coil.

The development of the ATLAS central solenoid magnet for the 2 Tesla is discussed. The design features high strength aluminum stabilized superconductor for stability.

A solid-state bonding method for fabricating cable-in-conduit conductor joints has been developed with respect to the specifications of the poloidal coil of the Large Helical Device. The technique, which has been applied to niobium-tin filaments, reduces the quench current in a joint to one-third of the conductor critical current. It also reduces the space requirement and magnetic field errors.

An experimental study on the stability of cable-in-conduit superconductors developed for the large helical device's poloidal field coils is presented. The conductor under investigation is the result of a new design that was made after tests revealed problems related to strand motion, current distribution and inter-filamentary current transition. Designed for operation at 20.8 kA and 6.5 T, it has a stability margin of 5x10(super 5) j/m3.

An experimental study was conducted on current transfer and sharing in superconducting joints. Hall probes were attached to the joint block to examine current sharing variations. Results demonstrate the transverse current redistribution in the joint during overall current increases. Results were in agreement with those calculated using a proposed current loop model.

A high-temperature superconducting dipole floating in the magnetic field of a normal conducting coil has been developed for the Ring Trap (RT)-1 plasma confinement apparatus at the University of Tokyo. The RT-1 device consists of the floating superconducting dipole, a levitation coil made of normal conductor, a vacuum vessel for plasma confinement and detachable services for the floating dipole. This paper describes the design concept and operating scenario of the floating dipole as well as the required services such as a HTS persistent current switch necessary to realize this scenario. [ABSTRACT FROM AUTHOR]

A thin superconducting solenoid has been constructed for ATLAS, one of the four LHC experiments at CERN. The single layer coil wound with an AI stabilized NbTi superconductor, with overall dimensions of 5.3 m length and 2.6 m diameter and operating at 7.6 kA provides the 2 T magnetic field for the inner detector. The coil was successfully tested at the company before shipment and re-tested at CERN on surface in its final configuration before commencing the installation in the ATLAS cavern 100 m underground. The tests include an extensive study of the quench evolution and in particular the normal zone propagation through the coil windings and in the superconducting bus-lines. A special feature of this coil is the use of aluminum quench propagation strips glued to the windings inner surface. This design enhances the turn-to-turn normal zone propagation velocity, reaching up to 0.8 m/s, and limits the hot spot temperature to 110 K. Along the conductor, normal zone propagation reaches velocities up to 14 m]s at nominal current. [ABSTRACT FROM AUTHOR]

The ATLAS detector for the LHC at CERN requires a superconducting solenoid, which provides the magnetic field for the inner detector. The ATLAS Central Solenoid and its associated proximity cryogenics system has been designed by KEK in collaboration with CERN. Following construction and preliminary tests at Toshiba in Japan the equipment has been shipped to CERN. The system is being prepared for the integration in the common cryostat with the LAr calorimeter, whereafter a full on-surface test has to be completed before its final installation 100 m underground in the ATLAS cavern. For this purpose a provisional set-up for commissioning of the final proximity cryogenics, the connecting chimney and the solenoid has been established. A number of tests and simulations have been conducted in applying a new process control system to validate the cryogenics functionalities, the electrical powering scheme as well as the magnet control and safety systems. The present status of the solenoid project and the results of the various cryogenic and electrical tests are reported. [ABSTRACT FROM AUTHOR]