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DE 1 Plasma Wave Instrument (PWI) Step Frequency Correlator Electric and Magnetic Field Spectral Density

(2023). DE 1 Plasma Wave Instrument (PWI) Step Frequency Correlator Electric and Magnetic Field Spectral Density [Data set]. NASA Space Physics Data Facility. https://doi.org/10.48322/cb14-a164 (CiteAs link). Accessed on .

ResourceID
spase://NASA/NumericalData/DE1/PWI/SFC/PT0.25S

Description

Two Dynamics Explorer (DE) spacecraft were launched August 3, 1981, and placed into coplanar polar orbits with DE-1 in a highly elliptical orbit and DE-2 in a lower more circular orbit. The primary objective of the DE program was to investigate magnetosphere-ionosphere-atmosphere coupling processes. The DE mission provided a wealth of new information on a wide variety of magnetospheric plasma wave phenomena including auroral kilometric radiation, auroral hiss, Z mode radiation, narrow-band electromagnetic emissions associated with equatorial upper hybrid waves, whistler mode emissions, wave-particle interactions stimulated by ground VLF transmitters, equatorial ion cyclotron emissions, ion Bernstein mode emissions, and electric field turbulence along the auroral field lines. These files contain calibrated, full resolution, data from the DE-1 Plasma Wave Instrument (PWI). This instrument was designed and built by the plasma wave group at The University of Iowa, Department of Physics and Astronomy, in collaboration with investigators at Stanford University's STAR Laboratory. It measured plasma wave phenomena and quasi-static electric fields using paired combinations of five PWI sensors: a 200m tip-to-tip long wire electric antenna deployed in the spacecraft spin plane, a 9m tip-to-tip tubular electric antenna deployed along the spacecraft spin axis, a short 0.6m electric antenna, mounted on the boom and oriented parallel to the long wire antenna, a magnetic loop antenna mounted on the boom and oriented to measure the component of the magnetic field parallel to the long wire antenna, and a magnetic search coil antenna, also mounted on a boom and oriented to measure the magnetic field parallel to the spacecraft spin axis. The PWI main electronics unit consisted of a Step Frequency Correlator (SFC), a Low Frequency Correlator (LFC), a Wideband Analog Receiver (WBR) and a Linear Wave Receiver (LWR). Only the SFC data are included in these files. The LFC data were provided in a companion fileset. A dataset containing available high rate WBR LWR data may be provided in the future. The SFC consisted of two Step Frequency Receivers (SFR-A and SFR-B) which provided amplitude measurements of the electric and magnetic fields from 100 Hz to 400 kHz and in-phase and quadrature-phase correlations of signals from any selected antenna pair. Phase data are not provided in these datasets.

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Details

Version:2.6.0

NumericalData

ResourceID
spase://NASA/NumericalData/DE1/PWI/SFC/PT0.25S
ResourceHeader
ResourceName
DE 1 Plasma Wave Instrument (PWI) Step Frequency Correlator Electric and Magnetic Field Spectral Density
AlternateName
Dynamics Explorer 1 PWI SFC Spectra
AlternateName
DE-A PWI SFC Spectra
DOI
https://doi.org/10.48322/cb14-a164
ReleaseDate
2023-10-09 12:34:56.789
RevisionHistory
RevisionEvent
ReleaseDate
2020-07-07 21:14:31
Note
Only known prior ReleaseDate of the metadata
RevisionEvent
ReleaseDate
2023-07-30 12:34:56.789
Note
Added DOI and PublicationInfo minted by LFB, metadata versioned up to SPASE 2.6.0, reviewed by LFB 20230727
RevisionEvent
ReleaseDate
2023-10-09 12:34:56.789
Note
Added complete CDAWeb and HAPI AccessInformation, LFB 20231009
Description

Two Dynamics Explorer (DE) spacecraft were launched August 3, 1981, and placed into coplanar polar orbits with DE-1 in a highly elliptical orbit and DE-2 in a lower more circular orbit. The primary objective of the DE program was to investigate magnetosphere-ionosphere-atmosphere coupling processes. The DE mission provided a wealth of new information on a wide variety of magnetospheric plasma wave phenomena including auroral kilometric radiation, auroral hiss, Z mode radiation, narrow-band electromagnetic emissions associated with equatorial upper hybrid waves, whistler mode emissions, wave-particle interactions stimulated by ground VLF transmitters, equatorial ion cyclotron emissions, ion Bernstein mode emissions, and electric field turbulence along the auroral field lines. These files contain calibrated, full resolution, data from the DE-1 Plasma Wave Instrument (PWI). This instrument was designed and built by the plasma wave group at The University of Iowa, Department of Physics and Astronomy, in collaboration with investigators at Stanford University's STAR Laboratory. It measured plasma wave phenomena and quasi-static electric fields using paired combinations of five PWI sensors: a 200m tip-to-tip long wire electric antenna deployed in the spacecraft spin plane, a 9m tip-to-tip tubular electric antenna deployed along the spacecraft spin axis, a short 0.6m electric antenna, mounted on the boom and oriented parallel to the long wire antenna, a magnetic loop antenna mounted on the boom and oriented to measure the component of the magnetic field parallel to the long wire antenna, and a magnetic search coil antenna, also mounted on a boom and oriented to measure the magnetic field parallel to the spacecraft spin axis. The PWI main electronics unit consisted of a Step Frequency Correlator (SFC), a Low Frequency Correlator (LFC), a Wideband Analog Receiver (WBR) and a Linear Wave Receiver (LWR). Only the SFC data are included in these files. The LFC data were provided in a companion fileset. A dataset containing available high rate WBR LWR data may be provided in the future. The SFC consisted of two Step Frequency Receivers (SFR-A and SFR-B) which provided amplitude measurements of the electric and magnetic fields from 100 Hz to 400 kHz and in-phase and quadrature-phase correlations of signals from any selected antenna pair. Phase data are not provided in these datasets.

Acknowledgement
Users of the DE-1 PWI SFC data are encouraged to acknowledge NASA CDAWeb and The University of Iowa as the source of the data in any publication.
PublicationInfo
Authors
Gurnett, Donald, A.
PublicationDate
2023-01-01 00:00:00
PublishedBy
NASA Space Physics Data Facility
Contacts
RolePersonStartDateStopDateNote
1.PrincipalInvestigatorspase://SMWG/Person/Donald.A.Gurnett
2.MetadataContactspase://SMWG/Person/Jolene.S.Pickett
3.MetadataContactspase://SMWG/Person/Larry.J.Granroth
4.MetadataContactspase://SMWG/Person/Chris.W.Piker
5.MetadataContactspase://SMWG/Person/Lee.Frost.Bargatze
InformationURL
Name
The University of Iowa DE-1 PWI Page
URL
Description
Language
en
PriorIDs
spase://VWO/NumericalData/DynamicsExplorer1/PWI/SFC.PT0.25S
spase://VSPO/NumericalData/DynamicsExplorer1/PWI/SFC/PT0.25S
spase://VSPO/NumericalData/DE1/PWI/SFC/PT0.25S
AccessInformation
RepositoryID
Availability
Online
AccessRights
Open
AccessURL
Name
FTPS from SPDF (not with most browsers)
URL
ProductKey
DE1_PWI_SFC-SPECTRA
Description

In CDF via ftps from SPDF

AccessURL
Name
HTTPS from SPDF
URL
ProductKey
DE1_PWI_SFC-SPECTRA
Description

In CDF via https from SPDF

AccessURL
Name
CDAWeb
URL
ProductKey
DE1_PWI_SFC-SPECTRA
Description

Access to ASCII, CDF, and plots via NASA/GSFC CDAWeb

Format
CDF
Encoding
None
Acknowledgement
Users of the DE-1 PWI SFC data are encouraged to acknowledge NASA CDAWeb and The University of Iowa as the source of the data in any publication.
AccessInformation
RepositoryID
Availability
Online
AccessRights
Open
AccessURL
Name
CDAWeb HAPI Server
URL
Style
HAPI
ProductKey
DE1_PWI_SFC-SPECTRA
Description

Web Service to this product using the HAPI interface

Format
CSV
Acknowledgement
Users of the DE-1 PWI SFC data are encouraged to acknowledge NASA CDAWeb and The University of Iowa as the source of the data in any publication.
ProcessingLevel
Calibrated
InstrumentIDs
MeasurementType
Waves.Passive
MeasurementType
Spectrum
TemporalDescription
TimeSpan
StartDate
1981-09-16 05:21:48
StopDate
1984-06-28 20:35:55
Cadence
PT0.25S
Parameter #1
Name
Event time for the start of the sweep
ParameterKey
Epoch
Description

Spacecraft Event Time in UTC for the start of an SFR sweep. To get time offsets within a sweep add the corresponding values in the SubSweepTime array.

Support
SupportQuantity
Temporal
Parameter #2
Name
SFC Ex Receiver (1=A,2=B,3=both)
ParameterKey
Ex_Receivers
Description

Step Frequency Correlator has two independent Step Frequency Receivers, labeled 'A' and 'B'. This variable records which of the SFRs were connected to the Ex antenna during the collection of each record. This field will read: '1' if SFR-A was connected to Ex, '2' if SFR-B was connected to Ex, and '3' if both were used at different times during the 32 second sweep period.

Support
SupportQuantity
Other
Parameter #3
Name
SFC Es Receiver (1=A,2=B,3=both)
ParameterKey
Es_Receivers
Description

Step Frequency Correlator has two independent Step Frequency Receivers, labeled 'A' and 'B'. This variable records which of the SFRs were connected to the Es antenna during the collection of each record. This field will read: '1' if SFR-A was connected to Es, '2' if SFR-B was connected to Es, and '3' if both were used at different times during the 32 second sweep period.

Support
SupportQuantity
Other
Parameter #4
Name
SFC Ez Receiver (1=A,2=B,3=both)
ParameterKey
Ez_Receivers
Description

Step Frequency Correlator has two independent Step Frequency Receivers, labeled 'A' and 'B'. This variable records which of the SFRs were connected to the Ez antenna during the collection of each record. This field will read: '1' if SFR-A was connected to Ez, '2' if SFR-B was connected to Ez, and '3' if both were used at different times during the 32 second sweep period.

Support
SupportQuantity
Other
Parameter #5
Name
SFC B Receiver (1=A,2=B,3=both)
ParameterKey
B_Receivers
Description

Step Frequency Correlator has two independent Step Frequency Receivers, labeled 'A' and 'B'. This variable records which of the SFRs were connected to the B antenna during the collection of each record. This field will read: '1' if SFR-A was connected to B, '2' if SFR-B was connected to B, and '3' if both were used at different times during the 32 second sweep period.

Support
SupportQuantity
Other
Parameter #6
Name
Integer combining all data quality flags (0 = no issues detected)
ParameterKey
Quality_Flag
Description

A bitwise OR'ing of all known issue values for this record. The following issue values are defined. (0x2: Attenuation Mode) If this value is present the measurements are less sensitive than normal due to the input being attenuated by 30 dB. Though the data are still calibrated they do not have the same contrast as data collected in the un-attenuated state. (0x1: Gain Toggle Mode) If this value is present it means that the SFC was toggling attenuation states every 1/2 second. Measurements collected in the first half of the second are not attenuated. Measurements collected in the last half were attenuated by 30 dB. To achieve a single calibrated state for a single filter band in a record the attenuated measurements have been dropped. The final quality flag is a bitwise OR'ing of all issue values.

Support
SupportQuantity
Other
Parameter #7
Name
Spin Plane E-Field (SFC Ex) Spectra, 200 meter antenna, 104 Hz to 409 kHz
ParameterKey
Ex_Spectra
Description

These data are collected via the Long Wire Antenna (Ex) which has a frequency response range of DC to 2 MHz. It is constructed of two 100 meter wires deployed in the spacecraft spin plane held in place by a 5 g tip mass. The conductor is made of BeCu wire with 7 strands of 5-mil diam each. The effective electrical length is 173.1 meters DC and 101.4 meters AC.

Units
V^2 m^-2 Hz^-1
Structure
Size
512
Wave
WaveType
PlasmaWaves
WaveQuantity
ACElectricField
FrequencyRange
SpectralRange
RadioFrequency
Low
104
High
409000
Units
Hz
Parameter #8
Name
Spin Axis E-Field (SFC Ez) Spectra, 8 meter antenna, 104 Hz to 409 kHz
ParameterKey
Ez_Spectra
Description

These data are collected via the Tubular Electric Antenna (Ez) which has a frequency response range of DC to 2 MHz. It is constructed of two 4 meter tubes deployed along the spacecraft spin axis. The conductor is silver plated BeCu 2.8 cm diameter elements and has an effective electrical length of 8.0 meters DC and 5.0 meters AC.

Units
V^2 m^-2 Hz^-1
Structure
Size
512
Wave
WaveType
PlasmaWaves
WaveQuantity
ACElectricField
FrequencyRange
SpectralRange
RadioFrequency
Low
104
High
409000
Units
Hz
Parameter #9
Name
Spin Plane E-Field (SFC Es) Spectra, 0.6 meter antenna, 104 Hz to 100 kHz
ParameterKey
Es_Spectra
Description

These data are collected via the Short Electric Antenna (Es) which has a response range of 20 Hz to 100 kHz. It's constructed of two 10 cm diameter wire spheres separated by 0.6 meters with fiberglass booms. It is mounted on the PWI 6 meter boom oriented parallel to the long wire antenna (Ex). It's effective electrical length is 0.6 meters for AC signals.

Units
V^2 m^-2 Hz^-1
Structure
Size
512
Wave
WaveType
PlasmaWaves
WaveQuantity
ACElectricField
FrequencyRange
SpectralRange
RadioFrequency
Low
104
High
100000
Units
Hz
Parameter #10
Name
Spin Plane B-Field Spectra (SFC B), 1.0 m^2 loop, 104 Hz to 409 kHz
ParameterKey
B_Spectra
Description

These data are collected via the Magnetic Loop Antenna (B) which has a frequency response range of 100 Hz to 35 kHz for dB/dt and 35 kHz to 400 kHz response for B. It is constructed of a single loop of aluminum tubing of 0.8 by 1.25 meters in size covering 1.0 m^2 area and is mounted on the PWI 6 meter boom oriented to measure the spin-modulated component of B parallel to the long wire antenna, Ex.

Units
nT^2 Hz^-1
Structure
Size
512
Wave
WaveType
PlasmaWaves
WaveQuantity
ACMagneticField
FrequencyRange
SpectralRange
RadioFrequency
Low
104
High
409000
Units
Hz
Parameter #11
Name
Time offsets from the Epoch time for each spectra measurement in a sweep
ParameterKey
SubSweepTime
Description

If sub-sweep timing is not important to your application, this value can be ignored. Otherwise for each measurement add this time to the Epoch value for the record. There is one offset in this array for each measurement in the sweep

Units
s
Support
SupportQuantity
Temporal
Parameter #12
Name
Channel Frequency Centers (fixed), 512 (104.8 to 409610 Hz)
ParameterKey
Frequencies
Description

The SFC contained two Filter Receivers, SFR-A and SFR-B; this variable provides frequency channel centers for the two receivers. The same table is used for both SFR-A and SFR-B data.

Units
Hz
Support
SupportQuantity
Other
Parameter #13
Name
Wideband (waveform) data availability status
ParameterKey
WBR_xmit
Description

PWI Waveform data were transmitted directly from DE1 without going through the standard telemetry stream. This status field will read 0 if the wideband transmitter was off during this time period and thus waveform data were not transmitted. A 1 in this field indicates the transmitter was on and that waveform data may be available.

Support
SupportQuantity
Other