This paper studies, experimentally and theoretically, the grad-B drift transport and focusing of an intense electron beam. The Naval Research Laboratory’s Gamble II generator [J. D. Shipman, Jr., IEEE Trans. Nucl. Sci. NS-18, 243 (1971)] was used to drive a 900 kV, 850 kA beam. This beam drifted in the radial magnetic field gradient produced by an on-axis guide wire carrying a current of 40 kA. An additional axial magnetic field gradient generated by focusing spokes was used to radially compress the beam. Experimental diagnostics included radially resolved calorimetry and radiachromic film to study wall losses. Extensive simulations were performed to better understand the experiments. Energy transport efficiencies were slightly below 70%, and the focusing spokes were observed to compress the beam radius by approximately 10%.

Inductive Voltage Adder (IVA) accelerators were developed to provide high-current (100s of kA) power pulses at high voltage (up to 20 MV) using robust modular components. This architecture simultaneously resolves problems found in conventional pulsed and linear induction accelerators.A variety of highbrightness pulsed x-ray radiographic sources are needed from sub-megavolt to 16-MeV endpoints with greater source brightness (dose/spotz) than presently available. We are applying WA systems to produce very intense (up.to 75 TW/cma) electron beams for these flash radiographic applications.

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We present a solver for magnetic self-insulation diodes (SMID) Code, developed for studies on high-current relativistic diodes, and supply examples of its applied usage. In order to analyze experimental data and numerical simulation results an in-circuit approach has been developed with an appropriate theory elaborated.

The processes of a gas desorption and ions production were investigated during generation of microwave pulses in microsecond vircator. The influence of vacuum conditions was investigated and the velocity of cathode plasma was determined. Specific values of gas desorption and the partial composition was investigated for different cathodes. The parameters of the diode electron accelerator are the followings: beam energy 300 keV, beam current up to 10 kA, half-period 1,5 ps. Cathode and anode diameters are 10 cm and 20 cm, accordingly. Vacuum chamber diameter is 50 cm, anodecathode gap is 2 cm. The duration of microwave radiation is 0,5 p, wavelength is about 10 cm, output microwave power is about 1.5.108 W. Amount of gassing reaches 0.3 cm3. Ion energy reaches 200-300 keV value.