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Neutrons for Science
beams differ significantly, creating uncertainty in cosmological models. But to-date it is unclear whether this difference arises from experimental artefacts or profound physics136.
A second striking example of fundamental research at the ILL is the quest to determine the value of the electrical dipole moment (EDM) of the neutron; how close to zero is this fundamental quantity? For decades, scientists at the ILL have been pushing the experimental detection limits in order to set upper values for the EDM, which are of importance when discussing the theory of the weak interaction (one of the four fundamental forces of nature) and models of the origin of the Universe, especially its matter- antimatter asymmetry137.
11.5 Conclusions and future
We take this opportunity to look back at the more than 50 years of the ILL’s existence. The ILL very rapidly attained a high
level of productivity. By 1975, 7 years after the signature of the Intergovernmental Convention and only 4 years after the first criticality of the reactor (with many distinctive features - compact high neutron density core, large cold source, and many guide tubes), the ILL’s reactor source was operating for about 250 days per year.
136 Serebrov A.P., Fomin A.K., Physics Procedia 17, 199-205 (2011), DOI 10.1016/j.phpro.2011.06.037; Greene G.L. and Geltenbort P., Scientific American 314, 36-41 (2016), DOI 10.1038/scientificamerican0416-36
137 Serebrov A.P., et al., Crystallography Reports 61, 129-138 (2016), DOI 10.1134/S1063774516010193 237