The early development of neutron diffraction: science in the wings of the Manhattan Project

Abstract

Early neutron diffraction experiments performed in 1944 using the first nuclear reactors are described.

Research opportunities with compact accelerator-driven neutron sources

“…In the early years, the principal sources of neutron beams were the first nuclear reactors pursued in the course of developments for the atomic bomb. Researchers were mostly physicists investigating, on the side, what kinds of measurements would be possible [6]. Soon, scientists began to apply neutron scattering methods to probe the properties of materials rather than just characterizing the nuclear interactions.…”

“…[16,17] Figure 3.6 Estimated global neutron yield from low-energy nuclear reactions. [18] 6 Li(p,n) 6 Be, 7 Li(p,n) 7 Be, 9 Be(p,n) …”

“…[6] Today's high-power SPSSs include the MW-level sources, i.e., the Spallation Neutron Source (SNS) in the US and the Japan Spallation Neutron Source (JSNS of J-PARC), and the sub-MW-level sources, i.e., the ISIS at UK. Additionally, a MW-level steady-state spallation source, SINQ, has been in operation for twenty years in Switzerland.…”

A historical introduction to the symmetries of magnetic structures. Part 1. Early quantum theory, neutron powder diffraction and the coloured space groups

“…As the neutron sources created for the Manhattan project were finding new uses for fundamental science, Ernest Wollan led a series of fundamental investigations into neutron diffraction by monochromatised neutrons at the Oak Ridge National Laboratory (Shull et al, 1951, Mason et al, 2013. Part of this, a study by Clifford Shull and Samuel Smart of MnO (Shull and Smart, 1949), generated some very surprising results (Anderson, 2011) -they saw new diffraction peaks at low temperature ( Figure 1).…”

US Neutron Facility Development in the Last Half-Century: A Cautionary Tale

“…It was clear that the unique properties of the neutron offered powerful advantages for nuclear and other fundamental physics studies, for chemical analysis by neutron activation, and especially for probing the structure and dynamics of materials and molecules. 1 The sensitivity of neutron scattering to different isotopes, most notably hydrogen and deuterium, provided a powerful and unique tool to determine the structure of molecular and macromolecular materials, such as polymers. The neutron magnetic moment allows direct probing of the atomic-scale structure and properties of magnetic materials, which underpins modern computer technology; the deep and non-destructive penetration of materials by neutron beams allows unique imaging of materials and products, including modern-day fuel cells; and neutrons have extraordinary potential for the study of atomic and molecular dynamics in all classes of materials over nine orders of magnitude in time, from 10 -5 to 10 -14 seconds.…”