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The first one-meter long common coil dipole model (HFDC-01) that has single layer racetrack coils, a 22-mm wide 60 strand Rutherford-type cable made of 0.7mm Nb(sub 3)Sn strands is fabricated and tested at Fermilab. The model design parameters and fabrication procedures as well as the test results are discussed.

Research involving design of large-bore superconducting quadrupoles for the Advanced Hydrotest Facility ( AHF) is described and discussed.

A racetrack magnet using pre-reacted Nb[subscript 3]Sn cable is fabricated and tested at Fermilab.

Design of Nb[subscript 3]Sn low-beta quadrupoles for 2nd generation Large Hadron Collider (LHC) interaction regions (IR) is discussed.

Results of Nb[subscript 3]Sn strand-and-cable R&D under way in the High Field Magnet proram at Fermilab are reported. Magnets for the Very Large Hadron Collider (VLHC) are being developed.

Two short Nb[subscript 3]Sn dipoles, based on a single-bore cos-theta coil with a cold iron yoke have been designed and tested at Fermilab. The magnets' design and fabribcation procedures are described.

Development of a single-layer common-coil magnet is being finalized at Fermilab. The magnet, which incorporates innovative design and technology features, is meant to be used in a future Very Large Hadron Collider.

The influence of accelerator physics on the design of magnets for very high-energy hadron colliders is discussed. Limiting specifications of a very large hadron collider (VLHC) model are estimated, and their effect on the design of accelerator magnets is examined.

React and wind common coil dipoles for VLHC hadron colliders are investigated.

The fabrication of the shell-type Nb3Sn dipole magnet at Fermilab is discussed and test results are provided.

The Nb3Sn strands for Fermilab's high field dipole models were investigated and results of heat treatment optimization studies are reported.

The development of high field superconducting dipole NB3Sn magnets for very large hadron collider by Fermilab is discussed.

The design of a react-and-wind common coil dipole, including magnetic design, quench protection and mechanical support issues, is reported.

The results of a study into the design of a superconducting magnet with a two layer cosine-theta coil for Very Large Hadron Collider are reported, focusing on coil magnetization and iron saturation effects.

The results of magnetic, mechanical and quench protection analyses of the 11 T Nb3Sn dipole model being developed at Fermilab are reported.

The Large Hadron Collider Inner Triple Quadrupole Development Program at Fermilab is discussed.

The results of tests conducted on strip heaters intended for the Large Hadron Collider (LHC) are presented. The tests were performed on two locations on a 1.9-meter high gradient quadrupole model to study heater response times based on strip heater induced quenches and peak temperatures and quench velocities from spot heater induced quenches. The LHC interaction region is expected to be dependent on strip heaters for quench protection.

The steady-state and transient-current characteristics of superconducting leads used in the Tevatron at Fermilab has been investigated through a mathematical model. Results indicate that steady-state flows and temperatures are within 30% but the stabilization time discrepancy for the transient lead is between three to five. A possible reason for the discrepancy could be that the model assumes the exposed length does not change until a steady-state level is achieved.

The design, production experience and experimental results of the initial 2 m quadrupole magnet models are presented. The quadrupole magnets are being designed and tested by the Lawrence Berkeley National Laboratory and the Fermi National Accelerator Laboratory for the LHC Interaction Region inner triplets. The magnets have a nominal gradient of 205 T/m in a 70 mm bore and are designed to operate in a superfluid helium environment at a temperature of 1.9 degrees Kelvin.

Research was conducted to examine the performance of Bi-Sr-Ca-Cu-O superconducting quadrupole coils. The critical current performance of the coil at liquid helium and liquid nitrogen temperatures was measured. The critical current calculations at 4.2 K reveal a scale factor of 5.3 improvement over the 77 K performance. Its performance will be compared to short sample measurements of pieces of conductor taken from the start and finish of the windings.

A irradiation test was performed to a high temperature superconductor (HTS). wire using 8 giga electron volt protons to assess the radiation hardness of this material. Results revealed that the HTS wire has a total radiation dose of 10.8+- 1.0 megarad. It was also noted that its critical current, Ic remains unchanged even with its exposure to radiation. These findings confirm the usefulness of HTS as components of High Energy Particle Accelerators.

An investigation was conducted for a possible material for application at 1.9 K and 10.5 T in the insertion quadrupoles of LHC following a preliminary investigation of a new Nb-Ti-Ta alloy. A critical current density of 1550 A/mm2 at 10.5 T was achieved in a monofilament of this material. A lower 10.5 T critical current density of 1370 A/mm2 was reported for the initial multifilamentary production strand. A high atomic number region adjacent to the grain boundaries after heat treatment is suggested by high resolution FESEM electron backscatter images.

The development of a strand with improved current density at 10.5 T and 1.9 K over existing SSCL designs was initiated. Two of the successful strand designs used high Fe content Nb-47 wt%Ti alloys to improve the critical current density at high field by 7^%. Critical current densities over 1450 A/mm2 were obtained at 10.5 T and 1.9 K. The results showed that high resolution FESEM electronic backscatter contrast suggested a thin layer of high atomic number at grain boundaries.

The Brookhaven National Laboratory, Lawrence Berkeley National Laboratory and Fermilab are jointly developing a high gradient quadrupole for the LHC interaction regions. The design involves a two-layer, cos(2theta) coil geometry incorporated in a 70 mm aperture operating in superfluid helium conditions. Magnetic, thermal and mechanical design developments for cooling, high field quality and maximum gradient exceeding 250 T/m are described.

A study was conducted on the performance of Tevatron interactive region quadrupole under superfluid temperatures ranging from 1.8 K to 4.4 K. Performance was measured in terms of temperature and the protection quad heaters' effectiveness. Diffusion times were derived for different power densities, temperature and current levels. Results have potential applications in the design of magnets operating at superfluid conditions.

Fermilab is developing high gradient quadrupoles for applications in the Large Hadron Collider interaction regions at CERN. To gather information on ideal quadrupole designs, tests were conducted on a Tevatron low-Beta quadrupole cold mass. The quadrupole's temperature performance was compared to that of a mechanically-modified, heavily-instrumented version. The quadrupole exhibited excellent coil cooling and quench characteristics in superfluid helium conditions.

The low-β triplets of the Large Hadron Collider were designed and constructed by a world-wide collaboration officially formed in 1998. Over the course of the following years the collaboration worked to produce the triplet components, including four 215 T/m, 70 mm aperture quadrupoles, a DFBX distribution feedbox, and at the low luminosity interaction points a cold Dl beam separation dipole. In 2005 the first triplet was installed in the LHC tunnel, and at the end of 2007 hardware commissioning of the first triplets started. As of August 2008 five triplets have been successfully powered. This paper documents the processes and experience gained during the commissioning phase of the LHC. [ABSTRACT FROM AUTHOR]

Upgrades presently being planned for high-energy hadron colliders require magnet performance beyond the capabilities of NbTi superconducting wire. Recent improvements in the performance of Nb3Sn material and in the capability to use it in practical magnets make it the logical choice for the next generation of accelerator magnets. We discuss recent results of R&D programs, some remaining issues and possible solutions. Recent progress in understanding and in technical details of design and assembly have made Nb3Sn magnets easier to fabricate and more reliable in performance. [ABSTRACT FROM AUTHOR]

Fermilab is developing and investigating different high-field magnets (HFM) for present and future accelerators. The HFM R&D program focused on the 10-12 T magnets based on Nb3Sn superconductor and explored both basic magnet technologies for brittle superconductors-wind-and-react and react-and-wind. Magnet design studies in support of LHC upgrades and VLHC were conducted. A series of 1-m long cos-theta dipole models based on the wind-and-react technique was fabricated and tested. Three 1-m long flat racetracks and the common coil dipole model, based on a single-layer coil and react-and-wind technique, were also fabricated and tested. Extensive theoretical and experimental studies of electro-magnetic instabilities in Nb3Sn strands, cables and magnets were performed and led to a successful 10 T dipole model. This paper presents the details of Fermilab's HFM program, reports its status and major results, and formulates the next steps for the program. [ABSTRACT FROM AUTHOR]

The first one-meter long common coil dipole model (HFDC-01) has been fabricated and tested at Fermilab. This magnet has several innovative features such as: single-layer racetrack coils, a 22-mm wide 60-strand Rutherford type cable made of 0.7-inm Nb3Sn strands, and a stainless steel coil-support structure reinforced by horizontal bridges inserted between coil blocks. The model was instrumented with voltage taps, quench heaters, temperature sensors and strain gauges in order to monitor the quench origin, and to study mechanical and quench protection issues. This paper summarizes the model design parameters, the fabrication procedures and the test results. [ABSTRACT FROM AUTHOR]

A racetrack magnet, using Nb[sub 3]Sn superconducting cable reacted before winding, has been fabricated and tested at Fermilab. It consists of two flat racetrack coils, connected in a common-coil configuration, separated by a 5 mm thick fiberglass plate. Synthetic oil was used to prevent sintering of the strands during the heat treatment. The coils were wound and vacuum impregnated in the mechanical structure. The turn-to-turn insulation, consisting of Kapton® and pre-impregnated fiberglass tapes as wide as the cable, was wound together with the bare cable in order to form a continuous inter-turn spacer. The coils were instrumented with voltage taps, temperature sensors, spot heaters and quench heaters. The maximum current achieved was 12 675 A which is 78% of the short sample limit at 5.1 K (minimum temperature in the coil during 75 A/s ramp). Measurement of the temperature margin revealed a low degradation in the innermost turns. Quench performances at different temperatures and ramp rate effects have been measured and are presented and discussed. [ABSTRACT FROM AUTHOR]

Examines the design, fabrication and testing of superconducting niobium tin alloy-based dipole magnets with a cold iron yoke. Quench performance; Magnetic measurements; Field quality; Testing of quench heaters.

Examines the design and fabrication of a common coil dipole magnet made from niobium tin alloy superconductors. Application of the dipole for Very Large Hadron Collider; React-and-wind fabrication method; Coil winding.

Evaluates Fermilab's Nb[sub 3]Sn superconducting dipole magnets for future accelerators based on Nb[sub 3]Sn superconductors. Strand specifications; Piece lengths and Cu fractions of strands; Critical current measurements.

Describes the development of react and wind common coil dipoles for the Very Large Hadron Collider at the Fermi Accelerator Laboratory in Batavia, Illinois. Selection of Nb[sub 3]Sn wound after reaction to reduce costs; Horizontally split yoke design for the hybrid common coil; Magnetic design optimization.

Describes the fabrication of the shell-type Nb[sub 3]Sn dipole magnet at the Fermi National Accelerator Laboratory in Batavia, Illinois. Magnet and coil fabrication; Coil reaction; Use of vertically split iron yoke locked by two aluminum clamps and a stainless steel skin for the mechanical support structure.