We describe a simple electrostatic focusing method which efficiently damps transverse motion of a high-intensity (both high current and high particle energy) electron beam. The principle is to create an electrostatic central force anharmonic potential field which phase-mix damps transverse beam motion into increased beam emittance. The non-linear electrostatic field is created by a very resistive wire (L/R time approx. 2 ns) strung axially down the accelerator vacuum pipe. Positive-image charge equal to approx. 1/2 the negative-beam charge is induced onto the wire. Since the beam self fields cancel to within 1/..gamma../sup 2/, the resultant wire electric field dominates. Experimental results showing the guiding, focusing and damping of transverse motion will be presented.

The rich diversity of ideas and techniques for analyzing interconnected systems interaction has presented the NRC with the problem of identifying methods appropriate for their own review and audit. This report presents the findings of a preliminary study using the Digraph Matrix Analysis method to evaluate interconnected systems interactions for the safety injection system of Indian Point-3. The analysis effort in this study was subjected to NRC constraints regarding the use of Boolean logic, the construction of simplified plant representations or maps, and the development of heuristic measures as specified by the NRC. The map and heuristic measures were found to be an unsuccessful approach. However, from the effort to model and analyze the Indian Point-3 safety injection system, including Boolean logic in the model, singleton and doubleton cut-sets were identified. It is recommended that efforts excluding Boolean logic and utilizing the NRC heuristic measures not be pursed further and that the Digraph Matrix approach (or other comparable risk assessment technique) with Boolean logic included to conduct the audit of the Indian Point-3 systems interaction study.