Abstract
The Nanoscale Ordered MAterials Diffractometer (NOMAD) is neutron time-of-flight diffractometer designed to determine pair distribution functions of a wide range of materials ranging from short range ordered liquids to long range ordered crystals. Due to a large neutron flux provided by the Spallation Neutron Source SNS and a large detector coverage neutron count-rates exceed comparable instruments by one to two orders of magnitude. This is achieved while maintaining a relatively high momentum transfer resolution of a δQ/Q∼0.8% FWHM (typical), and a possible δQ/Qof0.24% FWHM (best). The real space resolution is related to the maximum momentum transfer; a maximum momentum transfer of 50 -1 can be obtained routinely and the maximum momentum transfer given by the detector configuration and the incident neutron spectrum is 125 -1. High stability of the source and the detector allow small contrast isotope experiments to be performed. A detailed description of the instrument is given and the results of experiments with standard samples are discussed.
| Original language | English |
|---|---|
| Pages (from-to) | 68-75 |
| Number of pages | 8 |
| Journal | Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms |
| Volume | 287 |
| DOIs | |
| State | Published - Sep 15 2012 |
Funding
We thank Chris Benmore for providing the sample that served as a standard for the GLAD diffractometer for long years. This research at Oak Ridge National Laboratory’s Spallation Neutron Source was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, US Department of Energy .
| Funders | Funder number |
|---|---|
| Scientific User Facilities Division | |
| U.S. Department of Energy | |
| Basic Energy Sciences | |
| Oak Ridge National Laboratory |
Keywords
- Neutron diffractometer
- Pair-distribution function
- Spallation Neutron Source