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in creator/contributor: "Hassenzahl, W.V."

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Quenches in the superconducting magnet CELLO

The superconducting magnet CELLO was tested with currents up to 3200 A at Saclay and has been installed at DESY in Hamburg where it will be used for particle physics experiments requiring colliding beams of electrons and positrons. The testing of this unique, large, one-layer solenoid provides an excellent opportunity to evaluate the theory of quench propagation under adiabatic conditions, that is, in a coil in which the conductors are not in direct contact with helium. In an early test of this… more

Date: January 1, 1979

Creator: Hassenzahl, W.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cost of high field Nb/sub 3/Sn and Nb-Ti accelerator dipole magnets

Future high-energy proton accelerators will likely require very high magnetic fields if the size of the accelerator and associated experimental areas are to be limited to dimensions that can be accommodated by the terrain at convenient sites. For example, the circumference of a 20 TeV, 10 T accelerator will be about 60 km. Two commercially available superconductors can be used to produce fields of 10 T or greater. The first is Nb/sub 3/Sn, which can operate in pool boiling helium at 4.4 K, the … more

Date: June 1, 1983

Creator: Hassenzahl, W.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A study of the effects of copper to superconductor ratio on stability

Accelerator dipole magnets operate with very low copper to superconductors ratios (R). This ability to operate with low R is significant in its impact on cost. The optimum value of R has been an issue of considerable debate. This study shows that the minimum propagating zone length is greatest for copper to superconductor ratios well below 1.5, which appears to be in contradiction with some of the data. 4 refs., 7 figs.

Date: August 1, 1988

Creator: Hassenzahl, W.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cost of high-field Nb/sub 3/Sn and NbTi accelerator dipole magnets

Future high-energy proton accelerators will likely require very high magnetic fields if the size of the accelerator and associated experimental areas are to be limited to dimensions that can be accomodated by the terrain at convenient sites. Two commercially available superconductors can be used to produce magnetic fields of 10T or more. The first is Nb/sub 3/Sn, which can operate in pool boiling helium at 4.4 K. The second is NbTi, which must be cooled to about 1.9 K in superfluid helium. In t… more

Date: November 1, 1982

Creator: Hassenzahl, W.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Heater induced quenches in SSC (Superconducting Super Collider) model dipoles

A 1-m long SSC dipole constructed at the Lawrence Berkeley laboratory was subjected to a series of heater induced quenches to determine: axial quench propagation velocities, transverse quench propagation, and conductor temperature rise. Quenches were produced by 3 heaters at different locations in the magnet and at several currents. The results of these studies are described and are compared to previously published theoretical studies of quenches on the SSC dipoles. These results are shown to b… more

Date: October 1, 1986

Creator: Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Source, origin, and propagation of quenches measured in superconducting dipole magnets

Transitions from the superconducting to normal state at 4.4 and 1.8 K in several model accelerator dipoles were recorded by a fast data-acquisition system. The resistive voltage rise in the conductor during the transitions is used to determine accurately the location of the quench source in the magnets and to estimate the axial and turn-to-turn quench velocities. The quench velocity, temperature evolution and energy deposition in the coil were calculated using the program QUENCH, and are in rea… more

Date: November 1, 1982

Creator: Caspi, S. & Hassenzahl, W.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Application of superconducting coils to VAR control in electric power systems: a proposal

During the last eight years, static VAR-control systems with thyristor-controlled, room-temperature reactors have been used in electrical systems for voltage control and system stabilization. In this proposal, we describe a new static VAR-control system that uses an asymmetrically controlled Graetz bridge and a superconducting dc coil. Preliminary studies indicate that the proposed system will have lower overall losses and that its capital cost and electrical characteristics are comparable to t… more

Date: November 1, 1979

Creator: Boenig, H. J. & Hassenzahl, W. V.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

1. 8K conditioning (non-quench training) of a model SSC dipole

The accepted hypothesis is that training quenches are caused by heat generation when conductors move under Lorentz force. Afterwards no conductor motion will occur until a higher field and greater Lorentz force acts. If superior heat transfer and/or greater temperature margin is provided by operating at lower bath temperature, one might expect that the heat generated by conductor motion will not cause a runaway temperature increase, or quench. To test this hypothesis, the central dipole field i… more

Date: September 1, 1986

Creator: Gilbert, W. S. & Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Superconducting magnetic energy storage

The U.S. electric utility industry transmits power to customers at a rate equivalent to only 60% of generating capacity because, on an annual basis, the demand for power is not constant. Load leveling and peak shaving units of various types are being used to increase the utilization of the base load nuclear and fossil power plants. The Los Alamos Scientific Laboratory (LASL) is developing superconducting magnetic energy storage (SMES) systems which will store and deliver electrical energy for t… more

Date: January 1, 1977

Creator: Hassenzahl, W. V. & Boenig, H. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Economic and system aspects of a superconducting magnetic energy storage device and a dc superconducting transmission line

No Description Available.

Date: January 1, 1974

Creator: McDonald, T.E. & Hassenzahl, W.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Test and evaluation of conductors for superconducting magnetic energy storage

Pancake coils of a monolithic conductor and several different types of braid and cable, using a variety of insulating tapes and bonding resins were constructed. The coils were tested to quench in self-field at currents up to 2700 A. Results are presented for the training behavior of the various coils as compared to short-sample tests. A conductor composed of several braids or cables in parallel, which will be suitable for the in situ fabrication of large magnets is described.

Date: January 1, 1976

Creator: Schermer, R. I. & Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Thin windows for gaseous and liquid targets: an optimization procedure

No Description Available.

Date: December 1, 1974

Creator: Hassenzahl, W.V. & Gray, W.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Workshop on stability in superconducting magnets, Los Alamos, New Mexico, July 25--29, 1977

The week-long Workshop on Stability in Superconducting Magnets sponsored by the Los Alamos Scientific Laboratory was a delightful technical success. Experts in theory and practice from all areas of the superconducting community met to discuss the intricacies of the stability problem. Detailed theory, recent data, computer interpretations of both, and engineering or design solutions to assure stability were presented. Emphasis of the workshop was mostly on the aspects of heat transfer necessary … more

Date: June 1, 1978

Creator: Hassenzahl, W.V. & Rogers, J.D. (comps.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Technology of superconducting accelerator dipoles

We discuss accelerator dipoles and their characteristics. Other types of magnets, in particular bubble chamber magnets have been quite successful. Their performance is based on cryogenic stability which is addressed only briefly in this chapter. This type of stability is not available to the accelerator designer because of the large quantities of copper or other stabilizer that would reduce the current density in the windings to an unacceptably low value.

Date: June 1, 1983

Creator: Hassenzahl, W.V.; Meuser, R.B. & Taylor, C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Sextupole correction coils for SSC model dipoles

Local correction of the sextupole error field is proposed for the dipoles of the SSC. This requirement is imposed on the design by the high field quality required both during injection at low fields and during colliding beam operation at high fields. Error fields in the main dipole windings due to superconductor magnetization and conductor misplacements and unwanted sextupole and decapole magnetic field terms. To correct the sextupole error field we have constructed sextupole coils made of a si… more

Date: May 1, 1985

Creator: Rechen, J.B.; Gilbert, W.S. & Hassenzahl, W.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development and tests of superconducting magnetic energy storage systems components

The major components of a superconducting magnetic energy storage system are briefly discussed. The electrical parameters of such a system are derived for constant power operation during magnet charging and discharging. A circuit to evaluate high current superconductors economically and nondestructively is described and test results for three different wires are presented. The second half of the paper deals with the design of an automated model SMES system which operates in a closed-loop power … more

Date: January 1, 1976

Creator: Boenig, H. J.; Turner, R. D. & Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Superconducting magnetic energy storage for electric utilities and fusion systems

Superconducting inductors provide a compact and efficient means of storing electrical energy without an intermediate conversion process. Energy storage inductors are under development for load leveling and transmission line stabilization in electric utility systems and for driving magnetic confinement and plasma heating coils in fusion energy systems. Fluctuating electric power demands force the electric utility industry to have more installed generating capacity than the average load requires.… more

Date: January 1, 1978

Creator: Rogers, J. D.; Boenig, H. J. & Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Superconducting energy storage development for electric utility systems

Model SMES experiments performed at LASL show that magnetic energy storage in a superconducting magnet is a viable alternate to energy storage methods which are being built today. It is a fast responding device, i.e., milliseconds, and efficient method which does not require electric energy be converted to mechanical form for storage. Component tests on a model SMES system include 12 pulse converter, automatic and manual converter power control system, and high current superconductors have been… more

Date: January 1, 1976

Creator: Turner, R. D.; Boenig, H. J. & Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

1-GWh diurnal load-leveling Superconducting Magnetic Energy Storage system reference design

A point reference design has been completed for a 1-GWh Superconducting Magnetic Energy Storage system. The system is for electric utility diurnal load-leveling but can also function to meet much faster power demands including dynamic stabilization. This study explores several concepts of design not previously considered in the same detail as treated here. Because the study is for a point design, optimization in all respects is not complete. This report examines aspects of the coil, the superco… more

Date: September 1, 1979

Creator: Rogers, J. D.; Hassenzahl, W. V. & Schermer, R. I. (comps.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Zinc contamination from brass upon heat treating a superconducting magnet

Theoretical calculations predicted that zinc outgassing from brass spacers during a planned heat treatment would likely damage a lab-scale superconducting magnet. This specter was reinforced by a simulated heat treatment, the samples of which were analyzed by gravimetry, metallography, and microprobe chemical analysis. It was found that zinc escaping from the brass could diffuse 80 {mu}m into copper electrical conductors and degrade their conductivity. To avoid this, steel was temporarily subst… more

Date: July 1, 1994

Creator: Stevens, D. W. & Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Safety analysis of the GEM Detector Magnet conductor

The safety of the GEM Detector Magnet is analyzed using a computational model to determine current sharing between the cabled conductor and the external aluminum stabilizer. The model includes inductive and transverse conductive effects due to the geometries of the coil and the conductor. A conservative analysis indicates a peak conductor hotspot temperature of {approximately} 50 K at two seconds after the initiation of quench. After this time, additional heating is limited because most of the … more

Date: August 27, 1993

Creator: Ferri, M. A. & Hassenzahl, W. V.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Flux shunts for undulators

Undulators for high-performance applications in synchrotron-radiation sources and periodic magnetic structures for free-electron lasers have stringent requirements on the curvature of the electron`s average trajectory. Undulators using the permanent magnet hybrid configuration often have fields in their central region that produce a curved trajectory caused by local, ambient magnetic fields such as those of the earth. The 4.6 m long Advanced Light Source (ALS) undulators use flux shunts to redu… more

Date: May 1, 1993

Creator: Hoyer, E.; Chin, J. & Hassenzahl, W. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Four-layer, two-inch bore, superconducting dipole magnet

Superconductors provide the accelerator designer with a unique opportunity to construct machines that can achieve high particle energies and yet have low operating costs. This paper describes the design, fabrication and testing of a 4 layer, 50 mm bore superconducting dipole magnet, D-9A. The magnet reached short sample, 5.8 T at 4.4 K and 8.0 T and 1.8 K, with little training, and exhibited low losses and low ramp rate sensitivity.

Date: November 1, 1982

Creator: Hassenzahl, W.V.; Peters, C.; Gilbert, W.; Taylor, C. & Meuser, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Magnetic field measurements of model SSC (Superconducting Super Collider) dipoles

To qualify for use in the Superconducting Super Collider, the 8000 or so 16 m long dipole magnets must pass a series of tests. One of these will be a set of warm measurements of field quality, which must be precise to about 0.001% of the 100 G field produced by 10 A, the maximum current the coils are allowed to carry for an extended period at room temperature. Field measurements of better than this accuracy have already been carried out on 1 m long model dipoles. These measurements have include… more

Date: October 1, 1986

Creator: Hassenzahl, W.V.; Gilbert, W.S.; Green, M.I. & Barale, P.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department