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

TL;DR

This paper introduces a novel neutron-scattering technique to directly measure the time-integral of the van Hove distribution function, providing new insights into system dynamics through elastic scattering measurements.

Contribution

It presents a new method to access the van Hove distribution function directly in the time domain, overcoming limitations of previous energy-exchange based approaches.

Findings

The method enables direct measurement of the running time-integral of I(t).

Numerical and simulation assessments demonstrate the feasibility of the approach.

The approach offers a new way to study system dynamics in neutron scattering experiments.

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.