100 Hz neutron radiography at the BOA beamline using a parabolic focussing guide

The recent developments in scientific complementary metal oxide semiconductor (sCMOS) detector technology allow for imaging of relevant processes with very high temporal resolution with practically negligible readout time. However, it is neutron intensity that limits the high temporal resolution neutron imaging. In order to partially overcome the neutron intensity problem for the high temporal resolution imaging, a parabolic neutron focussing guide was utilized in the test arrangement and placed upstream the detector in such a manner that the focal point of the guide was positioned slightly behind the scintillator screen. In such a test arrangement, the neutron flux can be increased locally by about one order of magnitude, albeit with the reduced spatial resolution due to the increased divergence of the neutron beam. In a pilot test application, an in-situ titration system allowing for a remote delivery of well-defined volumes of liquids onto the sample stage was utilized. The process of droplets of water (H₂O) falling into the container filled with heavy water (D₂O) and the subsequent process of the interaction and mixing of the two liquids were imaged with temporal resolution of 0.01 s. •Combination of neutron focussing device and use of sCMOS detector allows for very high temporal resolution neutron imaging to be achieved (albeit with reduced spatial resolution and field of view).•In-situ neutron imaging titration device for liquid interaction experiments.•Interaction of otherwise indiscernible liquids (H₂O and D₂O) visualized using neutron radiography with 0.01 s temporal resolution.