The NCNR Spin-Polarized Triple-Axis Spectrometer (SPINS)

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The NCNR Spin-Polarized Triple-Axis Spectrometer
(SPINS)
The SPINS instrument is located at the heart of
the cold neutron guide hall of the NIST Center
for Neutron Research.
SPINS
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The NCNR Spin-Polarized Triple-Axis Spectrometer
(SPINS)

• Incident Energy
• 14 2 meV ( 2.4 6.1 Å )
• Energy Resolution
• 0.02 1 meV
• Special Equipments
• Supermirror Transmission Polarizer
• A stack of single crystal Si plates with Fe/Si
  supermirror coatings
• Multi-crystal Analyzer
• 11 Horizontally Focusing PG Blades
• Position Sensitive Detector
• 3He, 20 25 cm2
• Filters
• PG or Be filters before sample
• Be or BeO filters after sample

The SPINS instrument with a super-conducting
magnet.
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The SPINS Operation Modes IConventional
Triple-Axis Spectroscopy (TAS)
A single point at a time
TAS is ideally suited for probing small regions
of phase space
Shortcoming Low data collection rate
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The SPINS Operation Modes II Horizontally
Focusing (HF) Analyzer Mode
Relaxed Q-resolution
Useful for studying systems with short-range
correlations
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The SPINS Operation Modes III Multiplexing
Detection System for TAS
1meV
qai qa D2qi qa - atan(x sinqa/(Lxcosqa)) kf
i ta/2sinqai Qi ki - kfi
Probes scattering events at different energy and
momentum transfers simultaneously
Survey (hw-Q) space by changing the incident
energy and scattering angle
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The SPINS Operation Modes IV Position-Sensitive
Detector in Two-Axis Mode
The filter passes only those neutrons with 0 lt Ef
lt Ecutoff
Large angular acceptance w / L 11o for SPINS