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The US LHC Accelerator Research Program (LARP) is developing Nb3Sn accelerator magnets for a possible LHC luminosity upgrade. As part of the LARP supporting R&D, a subscale racetrack quadrupole magnet (SQ) has been developed in order to provide a cost effective tool for technology development studies. The first magnet (SQ01), reported earlier, was tested as a proof-of-principle model that applied for the first time LBNL shell-based loading structure to Nb3Sn racetrack coils in a quadrupole configuration. The new loading structure, pre-loaded with water-pressurized bladders and keys, provided predictable and controllable pre-stress to four subscale racetrack coils, both in the end region and across the straight section. A second magnet (SQ02) has been recently completed, with the goal of assessing the conductor performance and the influence of the coil axial support on training. SQ02 implements four new coils wound around aluminum bronze islands and instrumented with voltage taps and spot heaters, in order to monitor quench locations and propagation velocities. This paper reports the SQ02 test results, including magnet quench performance with respect to short sample expectations, training history, and quench locations. [ABSTRACT FROM AUTHOR]

Magnet programs at BNL, LBNL and FNAL have observed instabilities in high Jc Nb3 Sn strands and magnets made from these strands. This paper correlates the strand stability determined from a short sample-strand test to the observed magnet performance. It has been observed that strands that carry high currents at high fields (greater than 10 T) cannot sustain these same currents at low fields (1-3 T) when the sample current is fixed and the magnetic field is ramped. This suggests that the present generation of strand is susceptible to flux jumps (FJ). To prevent flux jumps from limiting stand performance, one must accommodate the energy released during a flux jump. To better understand FJ this work has focused on wire with a given sub-element diameter and shows that one can significantly improve stability by increasing the copper conductivity (higher residual resistivity ratio, RRR, of the Cu). This increased stability significantly improves the conductor performance and permits it to carry more current. [ABSTRACT FROM AUTHOR]

The article focuses on the IEEE Council on Superconductivity Awards in Applied Superconductivity Presented at 2004 Applied Superconductivity Conference. The IEEE Awards in Applied Superconductivity, sponsored by the IEEE Council on Superconductivity, were presented during the Applied Superconductivity Conference 2004, which was held in Jacksonville FL on October 3-8, 2004. These Awards, approved by the Institute of Electrical and Electronic Engineers (WEE), were established to recognize researchers, engineers and managers, who, during their professional careers, have made outstanding contributions to the field of applied superconductivity.

From the standpoint of overall conductor cost, it is desirable to minimize the amount of Cu that is co-processed with the superconductor during strand fabrication. We are investigating several approaches for fabricating multistrand cables in which the Cu is added at the final, i.e., cabling, stage of manufacture. These include mixed strand Rutherford-type cables with pure Cu strands cabled together with superconductor strands that have a low volume fraction of Cu, Cu added as a core to a Rutherford-type cable, and Cu strip added to the surface of the cable. Results on fabrication of several alternate types of Nb3Sn cables are presented. The more promising types of mixed strand and cored cables are being evaluated in short sample and small magnet tests. These results will be presented and the performance will be compared with conventional Rutherford cables where the Cu is an integral component of the superconductor strand. [ABSTRACT FROM AUTHOR]

The article provides information on several awards. The Institute of Electrical & Electronics Engineers (IEEE) provides awards for professionals who made significant contributions in the field of applied superconductivity. The Cryogenic Society of America presents The Roger W. Boom Award to young people whose accomplishments were related to cryogenic engineering and applied superconductivity. The SUPERCONDUCTOR WEEK awards are given to individuals for their works in applied superconductivity.

This index covers all technical items - papers, correspondence, reviews, etc. - that appeared in this periodical during the year, and items from previous years that were commented upon or corrected in this year. Departments and other items may also be covered if they have been judged to have archival value. The Author Index contains the primary entry for each item, listed under the first author's name. The primary entry includes the coauthors' names, the title of the paper or other item, and its location, specified by the publication abbreviation, year, month, and inclusive pagination. The Subject Index contains entries describing the item under all appropriate subject headings, plus the first author's name, the publication abbreviation, month, and year, and inclusive pages. Note that the item title is found only under he primary entry in the Author Index. [ABSTRACT FROM PUBLISHER]

Nb3Sn strands for high-current, high-field magnets must be cabled before reaction while the conductor is still composed of ductile components. Even though still in the ductile, deformable state, significant damage can occur in this step, which expresses itself by inhomogeneous A15 formation, Sn leakage or even worse effects during later reaction. In this study, we simulate cabling damage by rolling recent high performance powder-in-tube (PIT) and internal tin (IT) strands in controlled increments, applying standard Nb3Sn reaction heat treatments, and then examining the local changes using magneto-optical imaging (MOI), scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). These combined characterizations allow any local damage to the filament architecture to be made clear. MOI directly reveals the local variation of superconductivity while CLSM is extremely sensitive in revealing Sn leakage beyond the diffusion barrier into the stabilizing Cu. These techniques reveal a markedly different response to deformation by the PIT and IT strands. The study demonstrates that these tools can provide a local, thorough, and detailed view of how strands degrade and thus complement more complex extracted strand studies. [ABSTRACT FROM AUTHOR]