Wind SMS/STICS: Ion Velocity Distribution Functions in Magnetosphere

Wind spacecraft data includes 3-minute 3D velocity distribution functions for selected ion species using triple and double coincidence measurements. The Suprathermal Ion Composition Spectrometer (STICS) instrument measures ions over an energy per charge range of 6 - 200 keV/e, combining electrostatic analyzer, time-of-flight, and solid-state detector measurements. The data is provided by the National Aeronautics and Space Administration.

Use Cases

• Analyze ion velocity distributions based on triple-coincidence measurements for species like H+, He+, and Fe10+.
• Compare signal-to-noise ratios based on triple-coincidence versus double-coincidence measurement techniques.
• Study 3D velocity distribution functions based on the instrument's nearly 4π steradian viewing area from spacecraft spin.
• Investigate ion identification limitations based on double-coincidence measurements for select ions well-separated in E/Q - TOF space.

Strengths

• Data includes statistical errors for the velocity distribution functions.
• The triple-coincidence technique greatly improves signal-to-noise ratio.
• Double-coincidence measurements provide better statistics by counting ions not registered by the SSD.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Measured by the Wind spacecraft's Suprathermal Ion Composition Spectrometer (STICS) instrument.

Geography

Magnetosphere