HELNED: Helium-3-free low-cost neutron detectors

We developed a technique for thermal neutron detection not making use of 3 He, also suitable for online real time monitoring of CASTOR spent fuel containers. As a neutron converter we used 6 LiF, being the neutron capture cross section of 6 Li very well known and with only an alpha and a triton in the exit channel. We can deposit thin layers of converter onto several different substrates, to be placed on top of solid state detectors or scintillators capable of efficiently detecting the decay products.