Version:2.2.9

NumericalData

ResourceHeader

ResourceName

SOHO Charge, Element, and Isotope Analysis System (CELIAS) Proton Monitor 30 Second Solar Wind data

ReleaseDate

2018-02-27 16:46:59Z

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 cm2.

Acknowledgement

Please acknowledge the University of Maryland Space Physics Group

Contacts

	Role	Person
1.	PrincipalInvestigator	spase://SMWG/Person/Fred.M.Ipavich

InformationURL

Name

SOHO Celias Proton Monitor Home Page

URL

http://umtof.umd.edu/pm/

Description

Site hosting instrument information, some data and plots for SOHO Celias PM

PriorIDs

spase://VHO/NumericalData/SOHO/CELIAS/PT30S

AccessInformation

RepositoryID

spase://SMWG/Repository/NASA/GSFC/VHO-VMO

Availability

Online

AccessRights

Open

AccessURL

URL

https://vho.nasa.gov/mission/soho/celias_pm_30sec/

Description

CELIAS Proton Monitor repository at VHO

Format

Text

Encoding

ASCII

MeasurementType

ThermalPlasma

MeasurementType

Ephemeris

TemporalDescription

TimeSpan

StartDate

1996-01-20 20:17:30Z

RelativeStopDate

-P 5M

Cadence

PT30S

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

SupportQuantity

Temporal

Parameter #2

Name

Month

ParameterKey

Field 2

Description

String representation of month

Support

SupportQuantity

Temporal

Parameter #3

Name

Day

ParameterKey

Field 3

Description

Day of the Month

Support

SupportQuantity

Temporal

Parameter #4

Name

Time

ParameterKey

Field 4

Description

Colon seperated day of year, hour, minute and second (doy:HH:MM:SS)

Support

SupportQuantity

Temporal

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

GSE X

ParameterKey

Field 9

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 #10

Name

GSE Y

ParameterKey

Field 10

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 #11

Name

GSE Z

ParameterKey

Field 11

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 #12

Name

Heliocentric Range

ParameterKey

Field 12

Description

Heliocentric Range of SOHO in 10^6 km

Units

millions of km (10^6 km)

UnitsConversion

1e9>m

Support

SupportQuantity

Positional

Parameter #13

Name

Heliographic latitude

ParameterKey

Field 13

Description

Heliographic latitude of SOHO

Units

degrees

Support

SupportQuantity

Positional

Parameter #14

Name

Heliographic longitude

ParameterKey

Field 14

Description

Heliographic longitude of SOHO

Units

degrees

Support

SupportQuantity

Positional

Parameter #15

Name

Earth Carrington Rotation Number

ParameterKey

Field 15

Description

Earth Carrington Rotation Number

Support

SupportQuantity

Temporal