In neutron time-of-flight scattering, a form of

inelastic neutron scattering Neutron scattering, the irregular dispersal of free neutrons by matter, can refer to either the naturally occurring physical process itself or to the man-made experimental techniques that use the natural process for investigating materials. Th ...

, the initial position and velocity of a pulse of

neutron The neutron is a subatomic particle, symbol or , that has no electric charge, and a mass slightly greater than that of a proton. The Discovery of the neutron, neutron was discovered by James Chadwick in 1932, leading to the discovery of nucle ...

s are fixed, and their final position and the time after the pulse that the neutrons are detected are measured. By the principle of conservation of momentum, these pairs of coordinates may be transformed into momenta and energies for the neutrons, and the experimentalist may use this information to calculate the momentum and energy transferred to the sample. Inverse geometry spectrometers are also possible. In this case, the final position and velocity are fixed, and the incident coordinates are varied. Time-of-flight scattering can be performed at either a

research reactor Research reactors are nuclear fission-based nuclear reactors that serve primarily as a neutron source. They are also called non-power reactors, in contrast to power reactors that are used for electricity production, heat generation, or maritim ...

or a

spallation Spallation is a process in which fragments of material (spall) are ejected from a body due to impact or stress. In the context of impact mechanics it describes ejection of material from a target during impact by a projectile. In planetary p ...

source.

Time-of-flight spectrometers at pulsed sources

Time-of-flight spectrometers at pulsed sources include Pharos at LANSCE's Lujan Center at

Los Alamos National Laboratory Los Alamos National Laboratory (often shortened as Los Alamos and LANL) is one of the sixteen research and development Laboratory, laboratories of the United States Department of Energy National Laboratories, United States Department of Energy ...

, MAPS, MARI, HET, MERLIN and LET at the ISIS neutron source, and ARCS, CNCS, and SEQUOIA at the Spallation Neutron Source, iBIX, SuperHRPD, PLANET, SENJU, TAKUMI, iMATERIA and NOVA at the J-PARC and SKAT-EPSILON, DIN-2PI, NERA at the IBR-2 pulsed reactor.The IBR-2 instruments information
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Time-of-flight spectrometers at continuous sources

Time-of-flight spectrometers at continuous sources include DCS and FCS at the

NIST The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical s ...

laboratories in Maryland, IN4, IN5, and IN6 at the Institut Laue-Langevin, TOFTOF at the Forschungsneutronenquelle Heinz Maier-Leibnitz, PELICAN at the Australian Nuclear Science and Technology Organisation, FOCUS at the

Paul Scherrer Institute The Paul Scherrer Institute (PSI) is a multi-disciplinary research institute for natural and engineering sciences in Switzerland. It is located in the Canton of Aargau in the municipalities Villigen and Würenlingen on either side of the Ri ...

Related projects

Integrated Infrastructure Initiative for Neutron Scattering and Muon Spectroscopy (NMI3) is a European consortium of 18 partner organisations from 12 countries, including all major facilities in the fields of neutron scattering and muon spectroscopy.

References

Neutron scattering {{scattering-stub