The demonstration of ICF scientific feasibility requires success in target design, driver development and target fabrication. Since these are interrelated, we present here some results of ion beam target studies and relate them to parameters of interest to ion accelerators. Ion deposition physics have long been a well known subject apart from high beam currents. Recent NRL experiments at up to 250 kA/cm/sup 2/ ions confirm the classical deposition physics now at current densities which are comparable to most ion targets. On the other hand, GSI data at low current density but 1 to 10 MeV/nucleon are continually being accumulated. They have yet to find anomalous results. Relying on target concepts outlined briefly, we report on the energy gain of ion-driven fusion targets as a function of input energy, ion ranges and focal spot radius. We also comment on some consequences of target gain versus driver and reactor requirements.

The MFTF SNBPSS comprises a number of sources of potentially hazardous electrical energy in a small physical area. Power is handled at 80 kV dc, 80 A; 70 V dc, 4000 A; 25 V dc, 5500 A; 3 kV dc, 10 A; and 2 kV dc, 10 A. Power for these systems is furnished from two separate 480 V distribution systems and a 13.8 kV distribution system. A defense in depth approach is used; interlocks are provided in the hardware to make it difficult to gain access to an energized circuit, and the operating procedure includes precautions which would protect personnel even if no interlocks were working. The complexity of the system implies a complex operating procedure, and this potential complexity is controlled by presenting the procedure in a modular form using 37 separate checklists for specific operations. The checklists are presented in flowchart form, so contingencies can be handled at the lowest possible level without compromising safety.

The Ca II absorption lines observed in the late time optical spectra of Type I supernovae are analyzed in the context of the /sup 56/Ni model. The analysis indicates that a metal rich atmosphere of mass approx. 0.2 M/sub solar mass/ surrounds the /sup 56/Ni core. This result is consistent with properties of the atmosphere derived from spectra near maximum light.

Development of indirectly heated cathodes and duoplasmatron type electron feed assemblies is being pursued for use on positive ion sources of neutral beam systems. The cathodes utilize La/sub 2/O/sub 3/ doped molybdenum emission surfaces which supply ionizing electrons for a large rectangular (28 cm. x 60 cm.) magnetic multi-cusp confinement chamber. Single and double electron feed assemblies with different electrode geometries were tested at discharge currents of greater than or equal to 1000 A and pulse lengths of approx. 35 sec. Details of construction and performance results such as plasma uniformity are discussed.

The reconfiguration of MFTF to a tandem mirror machine with thermal barriers has caused a significant expansion in the physical scope of plasma diagnostics. From a mechanical perspective, it complicates the plasma access, system interfaces, growth and environmental considerations. Conceptual designs characterize the general scope of the design and fabrication which remains to be done.