Highly anisotropic, beam-like neutron emission with peak flux of the order of 10 9 n/sr was obtained from light nuclei reactions in a pitcher-catcher scenario, by employing MeV ions driven by a subpetawatt laser. The spatial profile of the neutron beam, fully captured for the first time by employing a CR39 nuclear track detector, shows a FWHM divergence angle of~ 70 , with a peak flux nearly an order of magnitude higher than the isotropic component elsewhere. The observed beamed flux of neutrons is highly favourable for a wide range of applications, and indeed for further transport and moderation to thermal energies. A systematic study employing various combinations of pitchercatcher materials indicates the dominant reactions being d(p, n+p) 1 H and d(d,n) 3 He. Albeit insufficient cross-section data are available for modelling, the observed anisotropy in the neutrons' spatial and spectral profiles is most likely related to the directionality and high energy of the projectile ions.

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High-intensity lasers are an effective source for the acceleration of high-energy particles. Using different interaction configurations, such facilities can be optimized for the acceleration of electrons, protons, heavy ions, high-energy photons, or neutrons. The shielding of these facilities to ensure the safety of personnel has always been a critical requirement and is a fundamental step within the design phase. The knowledge of radiation source terms through both experiments and modelling is now well understood and for the most part can be dealt with through the use of shielding and specialized beam dumps. Unlike most other particle accelerators most high-power laser facilities are still accessed by personnel post shot with little or no remote handling capabilities. As a result, the secondary activation and control of components that lie around the interaction is of great importance to safety. In this paper, we present a 10 year history of activation data on the Vulcan petawatt facility and discuss the primary sources of activation and the potential impact on future laser facilities.

This paper reports on a novel technique for rapid and cost effective manufacture of bespoke X-ray shielding. This technique is particularly well suited for producing prototypes of complex collimators for proof of concept and/or short duration usage. Instead of heavily investing in state-of-the-art 3D metal printing to create X-ray collimators, a conventional plastic 3D printer was used to create a hollow shell of the correct geometry which was filled with tungsten powder as the X-ray attenuating material. In this paper we have applied this technique to produce a complex collimator for energy dispersive X-ray diffraction (EDXRD), which could not be manufactured using conventional machining methods. We compare the performance of this collimator to a solid tungsten 3D printed example of the same design. EDXRD shows that the two collimators have very similar performance with the backfilled collimator having marginally worse peak resolution in momentum transfer, which is attributed to X-ray transmission through the plastic walls and the much lower packing fraction of the tungsten powder. This technique is widely accessible and is capable of rapid prototyping complicated collimator designs, whilst at 1% the cost of using a 2 tungsten 3D printing technique.