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We aim at building a compact accelerator-based neutron source (CANS) which would provide a thermal neutron flux on the order of 4x1012 n.s-1.cm-2.sr-1. Such a brilliance would put compact neutron sources on par with existing medium flux neutron research reactors for neutron scattering experiments. We performed the first neutron production tests on the IPHI proton accelerator at Saclay at a proton energy of 3 MeV. The thermal neutron flux were measured using gold foil activation and 3He detectors. The measured flux were compared with GEANT4 Monte Carlo simulations (10.4) in which the whole experimental setup was modelled. There is a good agreement between the experimental measurements and the Monte-Carlo simulations. The available modelling tools will allow us to optimize the whole Target Moderator Reflector assembly together with the neutron scattering spectrometer geometries for the design of the neutron scattering facility SONATE. [ABSTRACT FROM AUTHOR]

With the phasing out of many research reactors over the upcoming years, a shortcoming of small and medium sized neutron sources is to be expected. Laser-driven neutron sources have the potential to fill this void, with enormous progress being made in laser technology over the past years. Upcoming petawatt lasers with high repetition rates up to 10 Hz promise a tremendous increase in neutron flux. In this paper, a setup is developed and optimized to conduct neutron resonance spectroscopy at a laser-driven neutron source. This setup is then evaluated at an experimental campaign at the PHELIX laser system. Laser intensities up to 1021 W/cm² with a ns pre-pulse contrast of 10-7 were used for ion acceleration, resulting in (1.8±0.7)×108 N/sr per pulse corresponding to (2.3±1.0)×109 N in a 4 π equivalent. These pulses were moderated, collimated and investigated via the time of flight method in order to characterize the thermal neutron spectrum as well as the signal to noise ratio. [ABSTRACT FROM AUTHOR]

We describe the Compact Accelerator-based Neutron Source SONATE which we are aiming for to replace the closed Orphée reactor at Saclay, France. The SONATE source would serve an instrumental suite of about 10 instruments. The instruments would be split into low resolution instruments and higher resolution instruments. Our reference design is based on a proton accelerator operating at an energy in the range 20-30 MeV. The accelerator would serve 2 target stations. The first one operating at 20Hz with 2ms long pulses serving low resolution instruments (SANS, reflectivity, imaging, spin-echo) and the second one operating at 100Hz, 200μs long pulses serving higher resolution instruments (powder diffraction, Direct Time-of-flight spectroscopy, Indirect geometry spectroscopy). The 2 operation modes would be interlaced. The peak current on the target is aimed at 100 mA with an average power on the target on the order of 50-80 kW. Numerical Monte-Carlo simulations show that we may expect instrument performances equivalent to the current instruments around Orphée or ISIS. [ABSTRACT FROM AUTHOR]

The linac-based neutron source "iBNCT" developed by the Tsukuba team has been shown to generate a large intensity of neutrons. To confirm the applicability of the device to BNCT, several characteristic measurements have been implemented. In a water phantom experiment, when the accelerator was operated with an average current of 1.4 mA, the maximum thermal neutron flux was approximately 7.8 × 108 (cm-2s-1). From estimation of the stability of the linac, the results demonstrate its applicability to actual treatment. [ABSTRACT FROM AUTHOR]

Many small research reactors, neutron sources built in the 1950s and 1960s are being shut down. The activities that these supported have therefore ended, which motivates their replacements with new facilities. Compact accelerator-based neutron sources under development are able to take up many of those activities. This paper paints the background for these developments, summarizes the replacement technologies, relates recent work that supports them, and alludes to some of the new activities that they enable. [ABSTRACT FROM AUTHOR]

Neutron moderation properties from the cold mesitylene moderator have been studied. Kyoto University Accelerator driven Neutron Source has been used for these experiments. The container of the mesitylene moderator is situated in front of the polyethylene moderator and the change of the time of flight spectrum has been recorded as a function of the temperature of the mesitylene moderator. By fitting the Maxwell distribution to the obtained TOF spectra, the neutron temperature corresponding to the mesitylene temperature is estimated. [ABSTRACT FROM AUTHOR]

The TR-24 cyclotron (Advanced Cyclotron Systems Inc., Canada) of the Nuclear Physics Institute in Řež provides protons with variable energies from 18 MeV up to 24 MeV and beam current of 0.3 mA. For such parameters, the p +Be source reaction on thick Be target can produce a white-spectrum neutron field (En ≤ 22 MeV) with the intensity of 5×10 12 n/s/sr in forward direction. Present paper outlines the development of Be-target cooling system, devoted to remove the heat load of 7 kW (density up to 4 kW/cm2) from the target. Due to novel "orifice-form" of jet cooling (resulting in the shortest source-to- sample distance of 20 mm) with extremely high cooling efficiency, the TR-24 p-n convertor can achieve neutron-flux up to 2×1012n/cm2/s nearby the target output. [ABSTRACT FROM AUTHOR]

Recently, the possibility to use compact accelerators coupled to high current ion sources for the production of intense low energy proton or deuteron beams has motivated many research laboratories to develop accelerator based neutrons sources for several purposes, including Neutron Capture Therapy (NCT). The NCT needs a high flux, about 10 9 n.cm-2.s-1, of thermal neutrons (E<10 keV) at the tumour site. Up to now, the NCT required neutron flux was mainly delivered by nuclear reactors. However, the production of such neutron flux is now possible using proton or deuteron beams on specific targets able to stand a high pow er (~15- 30 kW) on a small area (~10 cm2). This specific target design, materials and supports, has to cope with extreme physical constraints. The LPSC team has conceived an original solution formed by a thin (8 μm) rotating beryllium target depos ited on a graphite wheel and coupled with a beryllium sputtering device for periodic 9Be layer restoration. By means of 9Be (d,n) 10B nuclear reaction, this target irradiated by a 10- -20 mA deuteron beam (1.45 MeV) should produce the required neutron flux. In order to validate the target design of the neutron flux production and the beryllium target thermal capabilities, we built a 30 cm diameter rotating Beryllium target prototype and a compact electron beam line able to deliver a power density of 3kW/cm2. [ABSTRACT FROM AUTHOR]

The Lund Broad-band Neutron Facility provides access to a variety of neutron sources together with a well-established user infrastructure. Neutrons from radioactive sources have been successfully employed for the research and development of both detectors and materials for the European Spallation Source. A recently procured d-t neutron generator delivers higher neutron fluxes than those provided by the radioactive sources, and further allows for pulsed operation. With the currently on-going construction of a dedicated neutron beam-line at our 3 MeV Pelletron accelerator, the facility is anticipated to produce approximately 1010 n/s. Cost-effective access to neutrons as well as a platform for educational purposes are the ultimate goals of the project. [ABSTRACT FROM AUTHOR]

We have constructed a compact accelerator-based neutron facility at the National Institute of Advanced Industrial Science and Technology (AIST) in Japan aiming at development of structural materials of transportation vehicles for weight reduction. The facility consists of electron linear accelerator, neutron source, and a neutron beamline with a measurement hutch. Currently we are commissioning the accelerator and expecting a first neutron beam in 2019. [ABSTRACT FROM AUTHOR]