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Data Access
FTPS from SPDF (not with most browsers)
HTTPS from SPDF
CDAWeb
WebService:
CDAWeb Programmatic Data Access
HAPI: CDAWeb HAPI Server
VMO UCLA
DE 2 2s Retarding Potential Analyzer (RPA) Ion Plasma Parameters
var authors='Heelis, Roderick, A.; Hanson, William, B.; Candey, Robert, M.';
document.write(authors);
(2023).
DE 2 2s Retarding Potential Analyzer (RPA) Ion Plasma Parameters.
[Data set].
Space Physics Data Facility; University of California, Los Angeles.
https://doi.org/10.48322/41b3-kz41. Accessed on document.write(currentDateStr);.
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ResourceID
spase://NASA/NumericalData/DE2/RPA/PT2S
Description
This data set contains the following plasma parameters at 16ms resolution from the DE 2 Retarding Potential Analyzer: ion drift velocity, ion temperature, densities of all ions and of O+, H+, He+, molecular, and high mass ions. Data are available in ASCII from nssdcftp and in CDF format from CDAWeb (as well as CDAWeb plots and lists). The data span the 18-month DE 2 lifetime, except for a gap from 1981/317 to 1982/041.
Metadata Rights
CC0-1.0:
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions. The actual data/software may be subject to a different license.
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Details
Version:2.7.1
NumericalData
ResourceID
spase://NASA/NumericalData/DE2/RPA/PT2S
NamingAuthority
NASA
ResourceType
NumericalData
ResourceHeader
ResourceName
DE 2 2s Retarding Potential Analyzer (RPA) Ion Plasma Parameters
AlternateName
Dynamics Explorer 2 RPA Ion Plasma
AlternateName
DE-B RPA Ion Plasma
DOI
https://doi.org/10.48322/41b3-kz41
ReleaseDate
2026-07-21 12:04:50Z
RevisionHistory
RevisionEvent
ReleaseDate
2021-04-27 15:38:11Z
Note
Only known prior ReleaseDate of the metadata
RevisionEvent
ReleaseDate
2023-07-30 12:34:56.789Z
Note
Added DOI and PublicationInfo minted by LFB, metadata versioned up to SPASE 2.6.0, reviewed by LFB 20230727
RevisionEvent
ReleaseDate
2025-10-02 15:11:48Z
Note
Updated PublishedBy name to match ROR Registry. Added ResourceType and NamingAuthority. Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. Matched version number in schemaLocation attribute to updated value in Version tag. ZCB
RevisionEvent
ReleaseDate
2025-12-04 13:29:08Z
Note
Added MetadataRightsList and RightsList(s). Updated to 2.7.1. ZCB
RevisionEvent
ReleaseDate
2026-06-26 13:16:45Z
Note
Add 'Z' to RevisionEvent:ReleaseDate(s), PublicationDate, TemporalDescription:TimeSpan:StartDate, TemporalDescription:TimeSpan:StopDate. ZCB
RevisionEvent
ReleaseDate
2026-07-21 12:04:50Z
Note
Added HelioData InformationURL. JWL
Description
This data set contains the following plasma parameters at 16ms resolution from the DE 2 Retarding Potential Analyzer: ion drift velocity, ion temperature, densities of all ions and of O+, H+, He+, molecular, and high mass ions. Data are available in ASCII from nssdcftp and in CDF format from CDAWeb (as well as CDAWeb plots and lists). The data span the 18-month DE 2 lifetime, except for a gap from 1981/317 to 1982/041.
Acknowledgement
Please acknowledge the RPA Principal Investigators, Drs. W.B. Hanson (original P.I.) and R.A. Heelis
PublicationInfo
Authors
Heelis, Roderick, A.; Hanson, William, B.; Candey, Robert, M.
PublicationDate
2023-01-01 00:00:00Z
PublishedBy
Space Physics Data Facility; University of California, Los Angeles
Contacts
Role
Person
StartDate
StopDate
Note
1.
PrincipalInvestigator
spase://SMWG/Person/Roderick.A.Heelis
2.
PrincipalInvestigator
spase://SMWG/Person/William.B.Hanson
3.
MetadataContact
spase://SMWG/Person/James.M.Weygand
4.
GeneralContact
spase://SMWG/Person/Robert.M.Candey
5.
MetadataContact
spase://SMWG/Person/Lee.Frost.Bargatze
InformationURL
Name
Readme file at SPDF
URL
https://spdf.gsfc.nasa.gov/pub/data/de/de2/plasma_rpa/00readme.txt
InformationURL
Name
NSSDC's Master Catalog on the Retarding Potential Analyzer (RPA)
URL
https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1981-070B-07
Description
The Retarding Potential Analyzer (RPA) measured the bulk ion velocity in the direction of the spacecraft motion, the constituent ion concentrations, and the ion temperature along the satellite path. These parameters were derived from a least squares fit to the ion number flux vs energy curve obtained by sweeping or stepping the voltage applied to the internal retarding grids of the RPA. In addition, a separate wide aperture sensor, a duct sensor, was flown to measure the spectral characteristics of iregularities in the total ion concentration. The measured parameters obtained from this investigation were important to the understanding of mechanisms that influence the plasma; i.e., to understand the coupling between the solar wind and the earth's atmosphere. The measurements were made with a multigridded planar retarding potential analyzer very similar in concept and geometry to the instruments carried on the AE satellites. The retarding potential was variable in the range from approximately +32 to 0 volts. The details of this voltage trace, and whether it was continuous or stepped, depended on the operating mode of the instrument. Specific parameters deduced from these measurements were ion temperature; vehicle potential; ram component of the ion drift velocity; the ion and electron concentration irregularity spectrum; and the concentration of H+, He+, O+, and Fe+, and of molecular ions near perigee. Additional details are in W. B. Hanson et al., Space Sci. Instrum., v. 5, n. 4, p. 503, 1981.
InformationURL
Name
HelioData
URL
https://helio.data.nasa.gov/dataset/DE2_RPA_PT2S
Description
The HelioData dataset page provides an overview of the dataset with access links, associated variables, and more.
PriorIDs
spase://VMO/NumericalData/DE2/VEFI/Ni.Vi.Ti/PT2S
spase://VSPO/NumericalData/DE2/RPA/PT2S
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb
Availability
Online
AccessRights
Open
RightsList
Rights
SchemeURI
https://spdx.org/licenses/
RightsIdentifierScheme
SPDX
RightsIdentifier
CC0-1.0
RightsURI
https://spdx.org/licenses/CC0-1.0.html
RightsName
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products
AccessURL
Name
FTPS from SPDF (not with most browsers)
URL
ftps://spdf.gsfc.nasa.gov/pub/data/de/de2/plasma_rpa/
Description
For ftp retrieval of daily CDF files
AccessURL
Name
HTTPS from SPDF
URL
https://spdf.gsfc.nasa.gov/pub/data/de/de2/plasma_rpa/
Description
In CDF via HTTP from CDAWeb
Format
CDF
DataExtent
Quantity
300
Units
KB
Per
P1D
Acknowledgement
Please acknowledge the RPA Principal Investigators, Drs. W.B. Hanson (original P.I.) and R.A. Heelis and the Space Physics Data Facility at NASA/GSFC
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb
Availability
Online
AccessRights
Open
RightsList
Rights
SchemeURI
https://spdx.org/licenses/
RightsIdentifierScheme
SPDX
RightsIdentifier
CC0-1.0
RightsURI
https://spdx.org/licenses/CC0-1.0.html
RightsName
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products
AccessURL
Name
CDAWeb
URL
https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=DE2_ION2S_RPA&index=sp_phys
ProductKey
DE2_ION2S_RPA
Description
For CDAWeb subset, plot and list capabilities
Format
Text
AccessDirectoryTemplate
https://cdaweb.gsfc.nasa.gov/pub/data/de/de2/plasma_rpa/ion2s_cdaweb/$Y
AccessFilenameTemplate
de2_ion2s_rpa_$Y$m$d_$v.cdf
DataExtent
Quantity
100
Units
KB
Per
PT1H
Acknowledgement
Please acknowledge the RPA Principal Investigators, Drs. W.B. Hanson (original P.I.) and R.A. Heelis and the Space Physics Data Facility at NASA/GSFC
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF
Availability
Online
AccessRights
Open
AccessURL
Name
CDAWeb Programmatic Data Access
URL
https://cdaweb.gsfc.nasa.gov/WS/cdasr/1/dataviews/sp_phys/datasets/DE2_ION2S_RPA/clientLibraryExample/
Style
WebService
ProductKey
DE2_ION2S_RPA
Description
Access to this data from common programming environments. Note: this AccessInformation element was added by HDPWS.
Format
Binary
Acknowledgement
Please acknowledge the RPA Principal Investigators, Drs. W.B. Hanson (original P.I.) and R.A. Heelis and the Space Physics Data Facility at NASA/GSFC
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb
Availability
Online
AccessRights
Open
RightsList
Rights
SchemeURI
https://spdx.org/licenses/
RightsIdentifierScheme
SPDX
RightsIdentifier
CC0-1.0
RightsURI
https://spdx.org/licenses/CC0-1.0.html
RightsName
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products
AccessURL
Name
CDAWeb HAPI Server
URL
https://cdaweb.gsfc.nasa.gov/hapi
Style
HAPI
ProductKey
DE2_ION2S_RPA
Description
Web Service to this product using the HAPI interface.
Format
CSV
Acknowledgement
Please acknowledge the RPA Principal Investigators, Drs. W.B. Hanson (original P.I.) and R.A. Heelis and the Space Physics Data Facility at NASA/GSFC
AccessInformation
RepositoryID
spase://SMWG/Repository/UCLA/DE2
Availability
Online
AccessRights
Open
AccessURL
Name
VMO UCLA
URL
http://vmo.igpp.ucla.edu/data1/DE2/RPA/ni_Ti_vi_2s_ascii/
Description
Dynamics Explorer 2 Retarding Potential Analyzer 2 s data
Format
Text
Encoding
ASCII
Acknowledgement
NASA; William B. Hanson; VMO
ProcessingLevel
Calibrated
InstrumentIDs
spase://SMWG/Instrument/DynamicsExplorer2/RPA
MeasurementType
ThermalPlasma
TemporalDescription
TimeSpan
StartDate
1981-08-06 00:00:00Z
StopDate
1983-02-16 00:00:00Z
Cadence
PT2S
ObservedRegion
Earth.NearSurface.Ionosphere