Helios 2 E6: Hourly Particle Fluxes from 0.3 to 1.0 AU

Helios 2 E6 data provides hourly averaged fluxes of electrons, protons, and alpha particles measured by the Helios-B deep space probe. The dataset, from NASA and the Federal Republic of Germany, covers the energy range 0.3 to 2.0 MeV for electrons, 4.0 to 51 MeV for protons, and 2.0 to 48 MeV for alpha particles, with measurements taken from 0.3 to 1.0 Astronomical Units from the Sun. It includes differential fluxes, integral fluxes for particles above certain energies, and for some channels, the standard deviations of the averages.

Use Cases

• Modeling solar energetic particle events based on multi-channel proton and alpha particle flux data.
• Analyzing the temporal evolution of cosmic ray fluxes based on hourly averaged measurements over the mission's range.
• Studying correlations between electron, proton, and alpha particle populations in interplanetary space.
• Validating space weather simulation outputs against historical in-situ particle measurements.

Strengths

• Data includes multiple particle types (electrons, protons, alphas) across several defined energy channels.
• Provides both differential and integral flux measurements, with some channels including standard deviations.
• Instrument was calibrated prior to launch using radioactive sources, particle accelerators, and ground-level muons.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• The energy boundaries for two electron channels (0.2 to 0.8 and 0.8 to 2 MeV) are described as only rough estimates.
• Negative rate values indicate missing or invalid data, which may require handling.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Measured by a particle telescope instrument on the Helios-B spacecraft.

Time Range

Coverage corresponds to the operational period of the Helios-B mission.

Freshness

Last updated 2026-03-13 07:04:05.657325; freshness should be verified.

Geography

Interplanetary space from 0.3 to 1.0 Astronomical Units from the Sun.