The objective of this work was to irradiate a Nb/sub 3/Sn superconductor with 14.8 MeV neutrons at 4 K and measure critical current in transverse fields of up to 12 T, irradiating up to a fluence sufficient to decrease the critical current to below its initial value. Critical temperatures were also to be measured. The samples were to be kept near 4 K between the irradiation and the measurement of critical properties. This work is directed toward establishing an engineering design fluence limit for Nb/sub 3/Sn when used in fusion reactor superconducting magnets.

The possibility of using Landau damping to reduce the growth of the beam size due to transverse wake fields has been known for some time. Recently K. Bane has calculated the effects of Landau damping for the SLC. The energy spread is then slowly removed so that at the end of the linac it has returned to the SLC specification of less than +0.5%. The purpose of the energy spread is to reduce the resonant driving of the tail of the bunch by the head. In this note the expected energy spreads within the beam are tabulated at various positions along the linac for use by those people designing momentum dependent equipment and for those interested in Landau damping.

For heavy-ion fusion energy applications, Mark and Yu have derived hydrodynamic models for numerical simulation of energetic pinched-beams including self-pinches and external-current pinches. These pinched-beams are applicable to beam propagation in fusion chambers and to the US High Temperature Experiment. The closure of the Mark-Yu model is obtained with adiabatic assumptions mathematically analogous to those of Chew, Goldberger, and Low for MHD. Features of this hydrodynamic beam model are compared with a kinetic treatment.

Recently revised estimates of target gain have added additional optimistic inputs to the interface between targets, accelerators and fusion chamber beam transport. But it remains valid that neutralization of the beams in the fusion chamber is useful if ion charge state Z > 1 or if > 1 kA per beamlet is to be propagated. Some engineering and economic considerations favor higher currents.

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Recent experiments on the TMX-U thermal barrier device at LLNL have achieved the end plugging of axial ion losses up to a central cell density of n/sub c/ = 2 x 10/sup 12/ cm. During these tests, the axial potential profile characteristic of a thermal barrier has been measured experimentally, indicating an ion-confining potential greater than 1.5 kV and a potential depression of 0.45 kV in the barrier region. The average beta of hot electrons in the thermal barrier has been increased to 15% and appears limited only by classical scattering and ECRH pulse duration. Furthermore, deuterium ions in the central cell have been heated with ICRF to an average energy of 1.5 keV, with a heating efficiency of 40%. During strong end plugging, the axial ion confinement time reached 50 to 100 ms while the nonambipolar radial ion confinement time was 5 to 15 ms - independent of end plugging. Radial ion confinement time exceeding 100 ms has been attained on shots without end plugging. Plates, floated electrically on the end walls, have increased the radial ion confinement time by a factor of 1.8. Further improvement in the central cell density during end plugging can be expected by increasing …

These results use the program ETRANS written by Harvey Lynch. ETRANS steps positrons produced in the target through a series of elements simulating the magnetic and accelerting fields of the flux concentrator, DC solenoids, and accelerating cavities. 13 figures, 1 table.

We use PATRICIA to study the quality of the multipolar contribution in the Window Frame Dipoles (WFD). In order to avoid possible noise with insetions, we only use 81 characteristics RHIC cell. As we want to make a comparison with available information on the Dedicated RHIC dipole (DRD), we only determine the apperture of WFD for some values of Δp/p.

On November 30, 1983, the LLNL Directorate met to discuss Laboratory policy regarding searches. An advance package (dated November 16, 1983) discussing background issues and DOE`s property protection and safeguards concerns was distributed to the Director and Associate Directors. A number of Associate Directors expressed concern about the nature of the theft problem at the Laboratory. There was also discussion about many employees` perception that Laboratory Management (including the Security Department) really did not care. The Director endorsed the need to establish searches in the SNM areas. The property protection type of searches were perceived as being very sensitive from a labor relations perspective. Nevertheless, the Directorate was sufficiently concerned about the safeguards and property protection issues to request the Security Department to develop a search plan for their review. A draft Search Program was prepared by the Security Department and reviewed individually with the Directorate for their comments. On March 19, 1984, the Directorate met collectively to consider a summary of these individual comments and to finalize a Search Program. Decisions made during that meeting have been incorporated into this document. This plan describes the search procedures that will be implemented at SNM areas and a two point program …