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Progress towards the development of a 20 cm sealed tube optical detector with imaging and photon event time stamping is presented. Novel microchannel plates employing borosilicate micro-capillary arrays have been tested. These provide many performance characteristics typical of conventional MCPs, but have been made in sizes up to 20 cm, have low intrinsic background (0.08 events cm^-2\ s^-1) and very stable gain behavior for at least 7 C \,\rm cm^-2 of charge extraction. Bialkali (Na2KSb) photocathodes with >20% quantum efficiency have also been made on 20 cm borofloat-33 windows compatible with a large sealed tube device. [ABSTRACT FROM PUBLISHER]

Conventional neutron radiography can be strongly enhanced by obtaining Bragg-edge information spatially correlated with the attenuation coefficient. This can now be achieved through time-of-flight techniques at pulsed neutron sources, utilising a neutron counting detector with high-spatial and high-temporal resolution. In these measurements, the positions of Bragg edges can in principle be obtained for each 55 × 55 μm2 pixel of the radiographic image. The combination of both Bragg-edge and attenuation information enables high spatial resolution studies to be carried out on material composition, phase transitions, texture variations, as well as residual strain mapping. In this article, we present the results of high-resolution strain maps of a ferritic steel cantilever sample measured at different loads by both transmission and conventional diffraction modes, as well as strains in an austenitic steel compact-tension (CT) crack sample. The proof of principle experiments performed on the ENGIN-X beamline on a bent cantilever arrangement resulting in a uni-axial stress field verified that the strain values measured in diffraction and transmission mode are in good agreement. The characteristics of the transmission mode detector as well as the measured strain maps and future possibilities of this technology are discussed. [ABSTRACT FROM AUTHOR]