Compact dielectric wall (DWA) accelerator technology is being developed at the Lawrence Livermore National Laboratory. The DWA accelerator uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. Its high electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The DWA concept can be applied to accelerate charge particle beams with any charge

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... o mass ratio and energy. Based on the DWA system, a novel compact proton therapy accelerator is being developed. This proton therapy system will produce individual pulses that can be varied in intensity, energy and spot width. The system will be capable of being sited in a conventional linac vault and provide intensity modulated rotational therapy. The status of the developmental new technologies that make the compact system possible will be reviewed. These include, high gradient vacuum insulators, solid dielectric materials, SiC photoconductive switches and compact proton sources. Applications of the DWA accelerator to problems in homeland security will also be discussed. We report on compact accelerator technology development for potential use as a pulsed neutron source quantitative post verifier. The technology is derived from our on-going compact accelerator technology development program for radiography under the US Department of Energy and for clinic sized compact proton therapy systems under an industry sponsored Cooperative Research and Development Agreement. The accelerator technique relies on the synchronous discharge of prompt pulse generating stacked transmission line structures with the beam transit. The goal of this technology is to achieve ~10 MV/m gradients for 10s of nanoseconds pulses and to ~100 MV/m gradients for ~1 ns systems. As a post verifier for supplementing existing x-ray equipment, this system can remain in a charged, stand-by state with little or no energy consumption. We detail the progress of our overall component development effort with the multilayer dielectric wall insulators (i.e., the accelerator wall), compact power supply technology, kHz repetition-rate surface flashover ion sources, and the prompt pulse generation system consisting of wide-bandgap switches and high performance dielectric materials. Alameda Applied Sciences Corporation (AASC) has built a bench-top source of fast neutrons (~10-40ns, 2.45MeV), that is portable and can be scaled to operate at ~100Hz. The source is a Dense Plasma Focus driven by three different capacitor banks: a 40J/30kA/100Hz driver; a 500J/130kA/2Hz driver and a 3kJ/350kA/0.5Hz driver. At currents of ~130kA, this source produces i ~3x10 6 (DD) n/pulse. The neutron pulse widths are ~10-40ns and may be controlled by adjusting the DPF electrode geometry and operating parameters. This paper describes scaling of fast neutron output from this Dense Plasma Focus, over a range of currents from 30 kA up to 350 kA. For each current and driver, different DPF head designs are required to match to the current rise-time, as the operating pressure and anode radius/shape are varied. Doping of the pure D 2 gas fill with Ar or Kr was shown ii to increase the neutron output. Results are discussed in the light of scaling laws suggested by prior iii literature. 25 fissions.s -1 . Rich neutron nuclei, produced by fission, will be extracted and accelerated in the existing cyclotrons of GANIL. The talk will describe the SPIRAL2 facility, the production mechanism and some radioactive aspects as it is calculated with Monte Carlo codes. Results of experiments estimating neutron production with possible solid and liquid converters (respectively graphite and heavy water) will also be presented.