The IBARAKI biological crystal diffractometer, iBIX, is a high-performance time-of-flight neutron single-crystal diffractometer for elucidating mainly the hydrogen, protonation and hydration structures of biological macromolecules in various life processes. Since the end of 2008, iBIX has been available to users' experiments supported by Ibaraki University. Since August 2012, an upgrade of the 14 existing detectors has begun and 16 new detectors have been installed for iBIX. The total measurement efficiency of the present diffractometer has been improved by one order of magnitude from the previous one with the increasing of accelerator power. In December 2012, commissioning of the new detectors was successful, and collection of the diffraction dataset of ribonucrease A as a standard protein was attempted in order to estimate the performance of the upgraded iBIX in comparison with previous results. The resolution of diffraction data, equivalence among intensities of symmetry-related reflections and reliability of the refined structure have been improved dramatically. iBIX is expected to be one of the highest-performance neutron single-crystal diffractometers for biological macromolecules in the world.

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The small‐angle neutron scattering spectrometer SANS‐U at the research reactor (JRR‐3) of the Japan Atomic Energy Agency, Tokai, Japan, has been successfully upgraded. This major upgrade was undertaken in order to install a high‐resolution position‐sensitive detector consisting of a cross‐wired position‐sensitive photomultiplier tube combined with a ZnS/6LiF scintillator on the SANS‐U spectrometer. Without changing the total length of the spectrometer, the aim was to extend the accessible low‐Q limit (Q is the magnitude of the scattering vector) and to shorten the measurement time by employing focusing small‐angle neutron scattering (FSANS). By using both spherical MgF2 biconcave lenses and the new high‐resolution position‐sensitive detector, the accessible low‐Q limit was extended from 2.5 × 10−3 to 3.8 × 10−4 Å−1. As a result, SANS‐U can continuously cover a wide Q range from 3.8 × 10−4 to 0.35 Å−1 with a wavelength of 7 Å. FSANS can be utilized not only to improve the accessible low‐Q limit but also to increase the intensity of incident neutrons passing through the sample in the conventional Q range from 2.5 × 10−3 to 0.35 Å−1. The use of `high‐intensity' FSANS also allowed a reduction of the measuring time by approximately 1/3.16 by increasing the incident neutron intensity.

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