Parker Solar Probe FIELDS: SCM Cross Spectra Data in Sensor Coordinates

NASA's Parker Solar Probe FIELDS experiment provides Level 2 cross spectra data from its Digital Fields Board (DFB) search coil magnetometer. The dataset contains power spectral densities, real/imaginary cross terms, coherence, and phase as functions of frequency and time, calibrated for instrument gain and filter responses. Data is expressed in sensor coordinates (u,v,w or d,e,f) with units of nT²/Hz for magnetic fields and V²/Hz for voltages.

Use Cases

• Analyzing wave-particle interactions in the solar wind based on magnetic field cross spectra.
• Studying plasma wave coherence and phase relationships across frequency bins.
• Investigating spectral slopes and features at high frequencies, noting the described calibration effects.
• Comparing magnetic field behavior across different solar orbits using the provided sensor coordinate systems.

Strengths

• Data is calibrated for multiple instrument responses including Hanning window, analog/digital filter gains, and preamplifier response.
• Provides both auto spectra (power spectral densities) and cross spectra (real/imaginary terms, coherence, phase).
• Cross spectra are averaged in frequency and time with either 56 or 96 spectral bins.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Voltage sensor data lacks corrections for plasma sheath impedance and antenna effective length, which are reserved for Level 3 products.
• Row count is unknown, which may limit suitability assessment.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Collected by the Digital Fields Board (DFB) instrument, the low-frequency (<75 kHz) component of the FIELDS experiment on the Parker Solar Probe spacecraft.

Time Range

Covers solar orbits, with coordinate systems differing for orbits 1-2 (d,e,f) and orbit 3+ (u,v,w).

Freshness

Last updated 2026-03 13 05:45:35.071575; freshness should be verified.

Geography

Data collected in space by the Parker Solar Probe in the inner heliosphere.