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To assess phenomena occurring in coaxial cables under high flux of 14 MeV neutrons in D-T fusion experiments, a Polyethylene, Teflon[TM] or vacuum sandwiched between two electrodes Mock-Up is proposed. This Mock-Up was exposed to the subnanosecond flux at the LLE OMEGA facility in Rochester (above [10.sup.18] n/[cm.sup.2]-s) normally to the electrodes or with a tilt angle. A radiation induced current probing a Radiation Induced Electromotive Force (RIEMF) is measured and a model is proposed based on the range of the neutron-induced recoils. The GEANT4 simulation toolkit has been used to take advantage of the implementation of both nuclear and electromagnetic processes in order to compute the tracks and the strong angle dependence. Good agreements between simulations and experimental results are found for Polyethylene in contrast with Teflon[TM] where the 3-[alpha] break-up of [sup.12]C not considered in GEANT4 seems to make a major contribution to the measured induced current. Comparison with the photon flux is made. Index Terms--Cable insulation, laser fusion, Monte Carlo neutron code, neutron radiation effects, RIEMF, SGEMP.

The single-event effects response of three different III-V field-effect transistor technologies (GaAs MESFET, InAIAs/InGaAs HEMT, and AISb/InAs HEMT) is measured for MeV and GeV heavy-ion irradiation. These measurements reveal significant charge enhancement and very slow, microsecond-timescale relaxation times for the GaAs and InAIAs/InGaAs devices, with a much faster recovery from the ionizing event observed for the AISb/InAs HEMTs. Index Terms--AISb, charge collection, GaAs, HEMT, InAIAs, InAs, InGaAs, InP, MESFET, single-event transient, single-event upset.