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The ion emission properties of laser-produced plasmas as a function of laser intensities between 4–50 GW cm−2 and varying angles with respect to the target normal were investigated. The plasmas were produced by focusing 1064 nm, 6 ns pulses from an Nd:YAG laser on various metal targets. The targets used for this study include Ti, Mo, and Gd (Z=22,42,64). It is noted that all ion profiles are composed of multiple peaks—a prompt emission peak trailed by three ion peaks (ultrafast, fast, and thermal). Experimentally, it is shown that each of these ion peaks follows a unique trend as a function of laser intensity, angle, and distance away from the target. Theoretically, it is shown that simple analytical models can be used to explain the properties of the ions. The variations in the ion velocity and density as a function of laser intensity are found to be in good agreement with theoretical models of sheath acceleration, isothermal self-similar expansion, and ablative plasma flow for various ion peaks.

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The Rotating Modulation Collimator has been modified to image thermal neutron sources. The components of the RMC imaging system were modified to suit thermal neutrons. The experiment compared two detectors (He3 and BF3) and two mask materials (cadmium and borated epoxy) for a 77mCi PuBe source. Preliminary results indicate that both He3 and BF3 detectors may be used with the RMC. Further efforts will be made to reduce the uncertainty in the system.