High-charge-state heavy-ions may reduce the accelerator voltage and cost of heavy-ion inertial fusion drivers, if ways can be found to neutralize the space charge of the highly charged beam ions as they are focused to a target in a fusion chamber. Using 2-D Particle-In- Cell simulations, we have evaluated the effectiveness of two different methods of beam neutralization: (1) by redistribution of beam charge in a larger diameter, preformed plasma in the chamber, and (2), by introducing a cold-electron-emitting source within the beam channel at the beam entrance into the chamber. We find the latter method to be much more effective for high-charge-state ions.

The Department of Energy has submitted to the NRC staff for review a topical safety analysis report (TSAR) for a Centralized Interim Storage Facility (CISF). The TSAR will be used in licensing the CISF when and if a site is designated. CISF1 design events are identified based on thorough review of design basis events (DBEs) previously identified by dry storage system suppliers and licensees and through the application of hazard assessment techniques. A Preliminary Hazards Assessment (PHA) is performed to identify design events applicable to a Phase 1 non site specific CISF. A PHA is deemed necessary since the Phase 1 CISF is distinguishable from previous dry store applications in several significant operational scope and design basis aspects. In addition to assuring all design events applicable to the Phase 1 CISF are identified, the PHA served as an integral part of the CISF design process by identifying potential important to safety and defense in depth facility design and administrative control features. This paper describes the Phase 1 CISF design event identification process and summarizes significant PHA contributions to the CISF design.

A recent result, relating the (irreversible) work performed on a system during a non quasistatic process, to the Helmholtz free energy difference between two equilibrium states of the system, is discussed. A proof of this result is given for the special case when the evolution of the system in question is modeled by a Langevin equation in configuration space.