Nuclear Resonant Scattering (NRS) is an experimental technique that uses pulsed, high-energy synchrotron radiation to obtain information on the hyperfine interaction between the nuclei in the sample.
The principle of NRS is based on Mössbauer spectroscopy. In Mössbauer spectroscopy, constant, monochromatic gamma radiation from a decaying excited nucleus is absorbed by nuclei in the sample, resulting in an absorption spectrum. In the absorption spectrum, hyperfine interaction of the nuclei in the sample can be seen from splitting or broadening of the absorption peaks.
A large difference between NRS and Mössbauer spectroscopy is the radiation that is sent to the sample. Instead of gamma rays, high-energy synchrotron X-ray radiation is used. This causes all hyperfine-split resonances to be excited at the same time. Also, the synchrotron radiation is not applied as a monochromatic beam, but as pulses. After each pulse, the excited states decay and these temporal decays interfere. This leads to a quantum beat pattern from which the hyperfine properties of the sample can be deduced. Because of this time behaviour, NRS is sometimes referred to as Mössbauer spectroscopy in the time domain.
An application of this technique is probing magnetism of ultra-thin iron films.