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Dynamics from elastic neutron-scattering via direct measurement of the running time-integral of the van Hove distribution function.

ABSTRACT: We present a new neutron-scattering approach to access the van Hove distribution function directly in the time domain, I(t), which reflects the system dynamics. Currently, I(t) is essentially determined from neutron energy-exchange. Our method consists of the straightforward measurement of the running time-integral of I(t), by computing the portion of scattered neutrons corresponding to species at rest within a time t, (conceptually elastic scattering). Previous attempts failed to recognise this connection. Starting from a theoretical standpoint, a practical realisation is assessed via numerical methods and an instrument simulation.

SUBMITTER: Benedetto A

PROVIDER: S-EPMC6677729 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Dynamics from elastic neutron-scattering via direct measurement of the running time-integral of the van Hove distribution function.

Benedetto Antonio A Kearley Gordon J GJ

Scientific reports 20190802 1

We present a new neutron-scattering approach to access the van Hove distribution function directly in the time domain, I(t), which reflects the system dynamics. Currently, I(t) is essentially determined from neutron energy-exchange. Our method consists of the straightforward measurement of the running time-integral of I(t), by computing the portion of scattered neutrons corresponding to species at rest within a time t, (conceptually elastic scattering). Previous attempts failed to recognise this ...[more]

PMID: 31375739

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