Version:2.6.0
NumericalData
ResourceID
spase://NASA/NumericalData/SOHO/CELIAS/PM/PT5M
ResourceHeader
ResourceName
SOHO Charge, Element, and Isotope Analysis System (CELIAS) Proton Monitor 5 Minute Solar Wind data
ReleaseDate
2023-10-17 00:00:00Z
RevisionHistory
RevisionEvent
ReleaseDate
2020-07-07 21:15:18Z
Note
Only known prior ReleaseDate of the metadata
RevisionEvent
ReleaseDate
2023-10-17 00:00:00Z
Note
Updated URLs, minor corrections, AK 20231017
Description
The Proton Monitor is a solar wind Energy per Charge (E/Q) analyzer of a new design, consisting of a three-box deflection system followed by a wedge-shaped MicroChannel Plate (MCP) assembly. The data are derived from sets of 6 rates (one for each voltage step of the PM deflection system) obtained every 30 seconds. The voltage steps are spaced logarithmically (about 60% step size) from about 0.3 to 3 kV. At a given voltage step the energy per charge dynamic range is slightly more than a factor of 2. The overall geometry factor of the PM is about 1.0 x 10^-4 cm^2.
Acknowledgement
Please acknowledge the University of Maryland Space Physics Group
Contacts
InformationURL
Name
SOHO Celias Proton Monitor Home Page
URL
Description
Site hosting instrument information, some data and plots for SOHO Celias PM
PriorIDs
spase://VHO/NumericalData/SOHO/CELIAS/PT5M
spase://VSPO/NumericalData/SOHO/CELIAS/PT5M
spase://NASA/NumericalData/SOHO/CELIAS/PT5M
AccessInformation
RepositoryID
Availability
Online
AccessRights
Open
AccessURL
Name
Proton Monitor Data at UMD
URL
Description
CELIAS Proton Monitor repository at UMD
Format
Text
Encoding
ASCII
InstrumentIDs
MeasurementType
ThermalPlasma
MeasurementType
Ephemeris
TemporalDescription
TimeSpan
StartDate
1996-01-20 20:17:30Z
RelativeStopDate
-P1M
Cadence
PT5M
ObservedRegion
Heliosphere.NearEarth
Caveats
On rare occassions the spacecraft's roll angle is changed for brief periods, during which the derived flow direction will refer to a different plane. A list of such times is available at http://umtof.umd.edu/pm/roll.html. In addition, since SOHO is not a spinning spacecraft, the deflection system was designed to have a wide angular acceptance (+- 15 deg). For technical reasons this leads to an ambiguity between incident angle and incident energy/charge; this ambiguity was designed into the PM to match as closely as possible the behavior of the deflection system for the main MTOF sensor. It is not the energy/charge but rather the mass/charge that is needed for interpretation of the MTOF mass data.
Parameter #1
Name
Year
ParameterKey
Field 1
Description
Two digit year
Support
Parameter #2
Name
Month
ParameterKey
Field 2
Description
String representation of month
Support
Parameter #3
Name
Day
ParameterKey
Field 3
Description
Day of the Month
Support
Parameter #4
Name
Time
ParameterKey
Field 4
Description
Colon seperated day of year, hour, minute and second (doy:HH:MM:SS)
Support
Parameter #5
Name
Proton Speed
ParameterKey
Field 5
Description
Proton Speed
Units
km/s
Particle
ParticleType
Proton
Qualifier
Magnitude
ParticleQuantity
Velocity
Parameter #6
Name
Proton Density
ParameterKey
Field 6
Description
Proton number density
Caveats
Parameters are derived from a combination of fitting and moment techniques
Units
cm^-3
Particle
ParticleType
Proton
Qualifier
Fit
Qualifier
Moment
ParticleQuantity
NumberDensity
Parameter #7
Name
Proton Thermal Speed
ParameterKey
Field 7
Description
Most probable proton thermal speed
Caveats
Parameters are derived from a combination of fitting and moment techniques
Units
km/s
Particle
ParticleType
Proton
Qualifier
Scalar
Qualifier
Moment
Qualifier
Fit
ParticleQuantity
ThermalSpeed
Parameter #8
Name
Proton arrival direction
ParameterKey
Field 8
Description
Proton arrival direction in degrees from north/south with positive meaning from the south
Units
degrees
Particle
ParticleType
Proton
Qualifier
DirectionAngle.ElevationAngle
ParticleQuantity
Velocity
Parameter #9
Name
Predicted Helium speed
ParameterKey
Field 9
Description
Predicted (not measured) Helium speed
Particle
ParticleType
Atom
ParticleQuantity
FlowSpeed
AtomicNumber
2
Parameter #10
Name
GSE X
ParameterKey
Field 10
Description
GSE X Component of SOHO position vector based on predicted orbit files ( 1 Re = 6378 km )
Units
Re
UnitsConversion
6.378e6>m
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
GSE
Support
SupportQuantity
Positional
Parameter #11
Name
GSE Y
ParameterKey
Field 11
Description
GSE Y Component of SOHO position vector based on predicted orbit files ( 1 Re = 6378 km )
Units
Re
UnitsConversion
6.378e6>m
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
GSE
Support
SupportQuantity
Positional
Parameter #12
Name
GSE Z
ParameterKey
Field 12
Description
GSE Z Component of SOHO position vector based on predicted orbit files ( 1 Re = 6378 km )
Units
Re
UnitsConversion
6.378e6>m
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
GSE
Support
SupportQuantity
Positional
Parameter #13
Name
Heliocentric Range
ParameterKey
Field 13
Description
Heliocentric Range of SOHO in 10^6 km
Units
millions of km (10^6 km)
UnitsConversion
1e9>m
Support
SupportQuantity
Positional
Parameter #14
Name
Heliographic latitude
ParameterKey
Field 14
Description
Heliographic latitude of SOHO
Units
degrees
Support
SupportQuantity
Positional
Parameter #15
Name
Heliographic longitude
ParameterKey
Field 15
Description
Heliographic longitude of SOHO
Units
degrees
Support
SupportQuantity
Positional
Parameter #16
Name
Earth Carrington Rotation Number
ParameterKey
Field 16
Description
Earth Carrington Rotation Number
Support