Upgrades allow smaller crystals and more challenging studies

Due to the low flux of even the most intense neutron sources, neutron macromolecular crystallography has historically been an intensity limited technique, requiring very large crystal volumes and long acquisition times. However, over the years, LADI-III has gone through a number of upgrades, such as its relocation in 2010 to the end-position of a new guide (H143), and these have dramatically reduced both the crystal volumes required and the data collection times. This has placed LADI-III's performance in a world-leading position, despite the more recent appearance of instruments at other neutron facilities, such as BioDiff at FRM-II, MaNDi at SNS and iBIX at J-Parc. The smallest crystals used, largest systems studied and fastest data collections have all been achieved using LADI-III. Currently, LADI-III utilizes a multilayer bandpass filter for wavelength selection. The replacement of the multilayer bandpass filter with a neutron velocity selector is a planned upgrade in 2026 that will increase the neutron transmission by a factor of ~2.

This upgrade will allow further reductions in the crystal volumes required or data collection times. In addition, it will provide more flexibility in terms of wavelength bandwidth choice so as to further optimize data collection strategies.