Another synchrotron-based method is Nuclear Inelastic Scattering (NIS), also known as Nuclear Resonant Vibrational Spectroscopy (NRVS). As the latter name indicates, its primary goal is to measure the vibrational properties (phonons) of solids or molecules. The basic information one wants to know in this respect is the density of states (DOS) of phonons: the number of vibration modes with a particular frequency.
Here are several resources to learn about NIS/NRVS. Inspect a least two of them, and try to understand them up to the point at which you are able to answer the question underneath.
Resources about NIS/NRVS:
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