BackForwardInstrument:  EPAM 

Instrument details
Acronym EPAM
Full name Electron, Proton, and Alpha-particle Monitor
Purpose To measure solar and interplanetary particle fluxes
Short description Assembly of two telecopes to measure spectra of ions Z from 1 to 28, energy/mass 0.045-92 MeV/n) and electrons (38-315 keV) with directional coverage of nearly a full unit sphere
Background Part of a package of instruments for solar observation
Scanning Technique Viewing the outer space tranvers to the Sun-Earth direction from the spinning ACE satellite on the L1 Lagrange libration point
Resolution N/A
Coverage / Cycle Large fraction of the interplanetary space, nearly continuous
Mass 6.4 kg Power 6.5 W Data Rate 160 bps

 

Providing Agency NASA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 1997 to 2027
Last update: 2021-11-10
Detailed characteristics
Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Solar and space environment monitors
  • Energetic particle spectrometer
WIGOS Subcomponents
  • Subcomponent 1
  • Solar wind in situ plasma and energetic particles, magnetic field, at L1
  • Solar wind at L1 - Electron sensor
  • Solar wind at L1 - Proton sensor
  • Solar wind at L1 - Alpha-particle sensor
  • Solar wind at L1 - Heavy ion sensor
  • Solar wind at L1 - Plasma density sensor
  • Solar wind at L1 - Plasma temperature sensor
  • Solar wind at L1 - Plasma velocity sensor
Mission objectives
Primary mission objectives
  • Solar wind density
  • Solar wind temperature
  • Solar wind velocity
Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
Note: * Primary mission objective.
VariableRelevance for measuring this variableOperational limitationsExplanation
Electron differential directional flux3 - highNo specific limitation.Interplanetary space, low and medium energy (up to 400 keV)
Proton differential directional flux3 - highNo specific limitation.Interplanetary space, medium and high energy (over 40 to over 1000 keV)
Alpha particles differential directional flux2 - very highNo specific limitation.Interplanetary space. Low-medium energy range (<10 up to 100 MeV/n)
Solar wind density*1 - primaryNo specific limitation.Interplanetary space. Infrerred from Proton. Electron and Alpha-particle spectroscopy
Solar wind temperature*1 - primaryNo specific limitation.Interplanetary space. Infrerred from Proton. Electron and Alpha-particle spectroscopy
Solar wind velocity*1 - primaryNo specific limitation.Interplanetary space. Infrerred from Proton. Electron and Alpha-particle spectroscopy
Heavy ion flux energy and mass spectrum4 - fairNo specific limitation.Interplanetary space. Low-medium energy range (<10 up to 100 MeV/n)