• R.R. Mitchell, D. Honaberger, B.A. Prichard
  LANL, Los Alamos, New Mexico
• M.E. Schulze
  SAIC, Los Alamos, New Mexico

The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) at Los Alamos National Laboratory (LANL) consists of two linear induction accelerators oriented at right angles to each other. The DARHT First produces a 60 ns pulse with a beam energy of 20 MeV and a beam current of 1.9 kA. The DARHT Second Axis produces a 1600 ns pulse with a nominal beam energy of 17 MeV and a beam current of 2 kA. The Second Axis Accelerator consists of 74 accelerating induction cells, each incorporating a solenoid comprised of twelve layers of copper conducting wire coated by a layer of insulating polymidemide and polyester. During the winding process, a coating of Castall E-301 epoxy was applied to the wire, forming the exterior boundary of the solenoid. The solenoids are cooled by low conductivity water flowing along the outside and inside surfaces of the solenoid. Recently, three solenoids developed electrical shorts within the winding. A comprehensive study has begun to determine the failure mechanism of the windings and to propose corrective measures. This paper describes the results of this study, which includes finite element analysis of the DARHT Second Axis accelerator cell solenoids.