Design and operation of the wide angular-range chopper spectrometer ARCS at the Spallation Neutron Source
D L Abernathy1, M B Stone, M J Loguillo
1Neutron Scattering Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. abernathydl@ornl.gov
The Review of Scientific Instruments
|February 4, 2012
Summary
The ARCS spectrometer at the Spallation Neutron Source (SNS) offers high neutron flux and detector coverage for condensed matter studies. Its design minimizes background scattering, enabling detailed investigations of lattice dynamics and magnetism.
Area of Science:
- Condensed matter physics
- Materials science
- Neutron scattering spectroscopy
Background:
- The Spallation Neutron Source (SNS) houses the ARCS spectrometer, designed for high-flux neutron scattering experiments.
- Optimizing neutron flux and detector coverage is crucial for advanced materials research.
Purpose of the Study:
- To detail the design and capabilities of the wide angular-range chopper spectrometer ARCS.
- To highlight novel features that enhance data quality and experimental efficiency.
- To confirm the instrument's performance through simulations and early results.
Main Methods:
- Utilizing an elliptically focused neutron guide and high-speed choppers.
- Employing a large array of helium-3 position-sensitive detectors.
- Implementing a window-free flight path by placing detectors within vacuum.
Main Results:
- ARCS provides high neutron flux and extensive detector coverage.
- Novel design features minimize background scattering for cleaner data.
- Instrument performance aligns with analytical and Monte Carlo simulations.
Conclusions:
- The ARCS spectrometer is operating as expected, with well-understood neutronic performance.
- Its capabilities facilitate diverse studies of excitations in condensed matter.
- Ongoing improvements aim to expand scientific productivity and data collection effectiveness.
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