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MMS 3 Hot Plasma Composition Analyzer (HPCA) Time of Flight, TOF, Counts, Level 2 (L2), Survey Mode, 0.625 s Data

Published by MMS_SDC, CDAWeb | National Aeronautics and Space Administration | Catalog Last Checked: August 12, 2026 at 12:41 AM | Dataset Last Updated: August 10, 2026
Hot Plasma Composition Analyzer (HPCA) Time of Flight, TOF, Counts, Level 2, Survey 10 s Data. The MMS HPCA instruments measure the energy and composition of magnetospheric plasmas in the energy range from 1 eV to 40 keV. An electrostatic energy analyzer (ESA) that is optically coupled to a carbon-foil based Time-of-Flight (TOF) section comprises each HPCA. The basic HPCA data product is an array of counts for 5 ion species, at 63 energies, for each of 16 elevation anodes. Sixteen basic products, also called azimuths, are acquired every 10 s; half a spacecraft spin period nominally has 16 azimuths. The five ion species are protons (H+), alpha particles (He++), helium ions (He+), singly charged Oxygen (O+), and background counts.

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Complete Metadata
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accessLevel public
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description Hot Plasma Composition Analyzer (HPCA) Time of Flight, TOF, Counts, Level 2, Survey 10 s Data. The MMS HPCA instruments measure the energy and composition of magnetospheric plasmas in the energy range from 1 eV to 40 keV. An electrostatic energy analyzer (ESA) that is optically coupled to a carbon-foil based Time-of-Flight (TOF) section comprises each HPCA. The basic HPCA data product is an array of counts for 5 ion species, at 63 energies, for each of 16 elevation anodes. Sixteen basic products, also called azimuths, are acquired every 10 s; half a spacecraft spin period nominally has 16 azimuths. The five ion species are protons (H+), alpha particles (He++), helium ions (He+), singly charged Oxygen (O+), and background counts.
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identifier https://doi.org/10.48322/2dfa-yh15
keyword 
[
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landingPage https://doi.org/10.48322/2dfa-yh15
license https://www.usa.gov/government-works
modified 2026-08-10
programCode 
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publisher 
{
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  "@type": "org:Organization"
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theme 
[
  "Heliophysics"
]
title MMS 3 Hot Plasma Composition Analyzer (HPCA) Time of Flight, TOF, Counts, Level 2 (L2), Survey Mode, 0.625 s Data

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