The resolution function in direct geometry neutron chopper spectrometers are fascinating. They exist up to 4 dimension in powder and single crystal experiments.
- Web app
- Experimental data for ARCS and SEQUOIA
- Published ARCS data
- Source code
The resolution function in direct geometry neutron chopper spectrometers are fascinating. They exist up to 4 dimension in powder and single crystal experiments.
Super resolution phonon Density of States from the ARCS instrument, a neutron Direct Geometry Chopper Spectrometer
Read Morepublished in Science on Oct 9, 2015. https://science.sciencemag.org/content/350/6257/193.
From Wikipedia: “A glacier is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries”
Glacier erosion power law was proposed by Jonathan Harbor, Bernard Hallet, and Charles Raymond, Nature, 1988.
But what is value of b, the power factor?
Sub-pixel image correlation techniques for satellite imagery were developed and used in this study to obtain accurate 3D model of the glacier surface, and then its moving speed, u, and helped constrain the value of b.
Flux and elastic resolution for a wide range of instrument conditions were measured and modeled for the ARCS chopper spectrometer.
This work provides a key reference for users of the ARCS instrument, making it easier for users to plan for their experiments. The online interactive resolution/flux plots make it much easier for ARCS users to take educated tradeoff between resolution and flux, while taking their experiment requirements into account.
Research details:
This work was published at https://doi.org/10.1016/j.physb.2018.11.027.
MCViNE: A software package for simulation of modern, complex neutron sample/sample environments, and detector systems. ~240k lines of C++/Python
Neutron Bragg edge modeling
A snapshot of a neutron CT reconstruction.
Neutron has greater penetration depths and has different cross section dependency on elements than X-ray. Neutron tomography can be used to study a variety of larger samples and is finding applications in engineering, material science, biology, and archeology. This package is in use by ORNL neutron imaging beamlines for neutron CT reconstructions.
A website for this calibration work is at https://sns-chops.github.io/SEQ-IDF-12292017/