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Voyager 2 LECP - Daily Average Interplanetary Data
var authors='Krimigis, Stamatios M.';
document.write(authors);
(2025).
Voyager 2 LECP - Daily Average Interplanetary Data.
[Data set].
Space Physics Data Facility.
https://doi.org/10.48322/gngy-ee60. Accessed on document.write(currentDateStr);.
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or other formats, should include the "Accessed on date" to identify the version of the resource being cited in a given publication.
ResourceID
spase://NASA/NumericalData/Voyager2/LECP/Particle/PT24H
Description
This data file contains 1 day averages of count rates for 11 energetic ion channels from the Low Energy Charged Particle (LECP) instrument on Voyager 2. The data listed are averaged over 24 hours, with the start time of the averging interval begining at the start of the day listed. For
example, 77/300 is an average over hours 0-23 on day 300 of 1977. Times are given in SCET-UT. The count rates R are in counts per second. The statistical uncertainty for each channel is the inverse square root of the total number of counts during each 24 hour period times the average count rate R. Included in the data table are the passbands in KeV for protons, the logarithmic mean energy Em for the differential energy channels, the geometric factor "g" (cm**2-steradian), and the flux conversion factor "f". To get from count rate R to differential in energy flux "dj(E)/dE", multiply R by f,
i.e.,
dj(E)/dE=f*R.
Note that f is simply the inverse of the energy passband multiplied by
the geometric factor. Generally one uses a more elaborate algorithm to
calculate fluxes by determining the local slope of the energy spectrum within
each energy passband, usually by an iterative algorithm, and then evaluating
the flux corresponding to each channel using this slope. However, if the
slope of the energy spectrum is not to steep, the approximation dj(E)/dE=f*R
is very good if the flux is evaluated at the mean energy Em=Sqrt(EL*EH),
where EL and EH are the low and high energy ends of the passband. Since the
slopes of low energy ion spectra in the interplanetary medium are in the
range of -1 to -3, the approximation is very good.
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/Voyager2/LECP/Particle/PT24H
NamingAuthority
NASA
ResourceType
NumericalData
ResourceHeader
ResourceName
Voyager 2 LECP - Daily Average Interplanetary Data
DOI
https://doi.org/10.48322/gngy-ee60
ReleaseDate
2026-02-17 18:48:01Z
RevisionHistory
RevisionEvent
ReleaseDate
2020-07-07 21:15:58Z
Note
Only known prior ReleaseDate of the metadata
RevisionEvent
ReleaseDate
2025-11-14 16:03:01Z
Note
Added PublicationInfo. Added ResourceType and NamingAuthority. ZCB
RevisionEvent
ReleaseDate
2025-12-04 13:32:36Z
Note
Added MetadataRightsList and RightsList(s). Updated to 2.7.1. ZCB
RevisionEvent
ReleaseDate
2026-02-17 18:48:01Z
Note
Added DOI. TLK
Description
This data file contains 1 day averages of count rates for 11 energetic ion channels from the Low Energy Charged Particle (LECP) instrument on Voyager 2. The data listed are averaged over 24 hours, with the start time of the averging interval begining at the start of the day listed. For
example, 77/300 is an average over hours 0-23 on day 300 of 1977. Times are given in SCET-UT. The count rates R are in counts per second. The statistical uncertainty for each channel is the inverse square root of the total number of counts during each 24 hour period times the average count rate R. Included in the data table are the passbands in KeV for protons, the logarithmic mean energy Em for the differential energy channels, the geometric factor "g" (cm**2-steradian), and the flux conversion factor "f". To get from count rate R to differential in energy flux "dj(E)/dE", multiply R by f,
i.e.,
dj(E)/dE=f*R.
Note that f is simply the inverse of the energy passband multiplied by
the geometric factor. Generally one uses a more elaborate algorithm to
calculate fluxes by determining the local slope of the energy spectrum within
each energy passband, usually by an iterative algorithm, and then evaluating
the flux corresponding to each channel using this slope. However, if the
slope of the energy spectrum is not to steep, the approximation dj(E)/dE=f*R
is very good if the flux is evaluated at the mean energy Em=Sqrt(EL*EH),
where EL and EH are the low and high energy ends of the passband. Since the
slopes of low energy ion spectra in the interplanetary medium are in the
range of -1 to -3, the approximation is very good.
Acknowledgement
Use of these data in publications should be accompanied by acknowledgements of the NASA Space Physics Data Facility, the National Space Science Data Center and the responsible Principal Investigator defined in the experiment documentation provided here.
PublicationInfo
Authors
Krimigis, Stamatios M.
PublicationDate
2025-11-14 16:03:01Z
PublishedBy
Space Physics Data Facility
Contacts
Role
Person
StartDate
StopDate
Note
1.
PrincipalInvestigator
spase://SMWG/Person/Stamatios.M.Krimigis
2.
TechnicalContact
spase://SMWG/Person/Robert.B.Decker
PriorIDs
spase://VSPO/NumericalData/Voyager2/LECP/Particle/PT24H
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF
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/voyager/voyager2/particle/lecp/daily/
Description
In ASCII via FTP from SPDF
AccessURL
Name
HTTPS from SPDF
URL
https://spdf.gsfc.nasa.gov/pub/data/voyager/voyager2/particle/lecp/daily/
Description
In ASCII via HTTP from SPDF
Format
Text
ProviderProcessingLevel
CALIBRATED
InstrumentIDs
spase://SMWG/Instrument/Voyager2/LECP
MeasurementType
EnergeticParticles
TemporalDescription
TimeSpan
StartDate
1977-09-07 00:00:00
StopDate
1994-12-30 23:59:59
Cadence
PT24H
ObservedRegion
Heliosphere