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During the last 36 years researchers have suggested and evaluated a large number of target designs for heavy ion inertial fusion. The different target designs can be classified according to their mode of ignition, their method of implosion, and their size. Ignition modes include hot-spot ignition and fast ignition. Methods of implosion include direct drive and indirect drive. Historically there has been significant work on indirectly driven targets with hot-spot ignition. Recently there has been increasing interest in directly driven targets with ion driven fast ignition. In principle, fast ignition might lead to improved target performance. On the other hand, fast ignition imposes stringent requirements on accelerators and beam physics. Furthermore, fast ignition magnifies the importance of a number of traditional target physics issues associated with ion beam energy deposition and fuel preheat. This paper will discuss the advantages and disadvantages of the various classes of targets. It will also discuss some issues that must be resolved to assess the feasibility of ion fast ignition.

A non-conventional theoretical approach for high-density beams in accelerator and storage rings is proposed and used to calculate the losses in the main ring of the HIDIF proposal.

The formula for the asymptotic level of polarization, when the beam energy in a synchrotron is accelerated uniformly across a single isolated depolarizing spin resonance, is given by the well-known Froissart–Stora formula. There is no analytical closed-form solution in the case of passage across two (or more) overlapping spin resonances. We present an approximate analytical closed-form formula for the asymptotic level of polarization for the passage across two overlapping spin resonances. We also present a quantitative criterion for the domain of applicability of our formula.

In this paper some problems of beam-lines optimization are discussed. The suggested approach makes available flexible and convenient tools both for the investigation of beam-line properties and for the synthesis of such systems using computer codes. This approach was developed as a natural result of the solution of practical problems from beam physics.

In this paper the role of distributed and parallel computing in beam physics is discussed. The natural parallel and distributed structures of beam physics problems allow the use of parallel and distributed computer systems. But the usual approaches based on traditional numerical methods demand using the resources of supercomputers. This leads to the impossibility of using such multiprocessing systems as computational clusters. In this paper some examples of beam physics problems are discussed from the computational point of view using clustered systems.

A detailed understanding of the physics of space-charge dominated beams is vital in the design of heavy ion inertial fusion (HIF) drivers. In that regard, low-energy, high-intensity electron beams provide an excellent model system. The University of Maryland Electron Ring (UMER), currently under construction, has been designed to study the physics of space-charge dominated beams with extreme intensity in a strong focusing lattice with dispersion. At 10 keV, 100 mA, the UMER beam has a generalized perveance in the range of 0.0015, corresponding to that of proposed HIF drivers. Though compact (11 m in circumference), UMER is a very complex device. In this paper, the unique design features of this research facility, the beam physics to be investigated, and recent experimental results in the prototype injector as well as simulation studies will be reviewed.

Various types of ERL sources are introduced, the relevant beam physics and accelerator technology issues noted, innovative areas of development identified and current and future goals of ERL research and development established.

The European negative ion based neutral beam development programme consists presently of experiments on high energy electrostatic accelerators and high current D − sources, and of neutral beam physics and system design studies. At CEA-Cadarache the source test bed MANTIS started operation last June, and the 1 MV, 0.1 A, D − acceleration project SINGAP will be operational by the end of 1994. Additionally, negative ion source physics-oriented experiments will be conducted at Dublin City University. A Pagoda source, developed for the SINGAP experiment, recently produced more than 1 A D − beams and j (D − ) of 10 mA cm −2 , with Cs seeding, at 0.6 Pa operating pressure. 1.3 A H − and 0.5 A D − beams have also been obtained without the use of Cs during the first experiments on MANTIS. Studies on neutral beam heating (NBH) for a next step machine have been conducted during 1993, mainly at JET and CEA-Cadarache. NBH physics studies based on the RLW model indicate that ignition on ITER-EDA should be reached with about 40 MW of 0.4–1 MeV D 0 beams. The outlines of an NBH system for ITER-EDA, based on SINGAP, have been studied.