2.3.2
spase://NASA/NumericalData/MMS/1/FIELDS/EDI/Burst/Level2/ElectricField/PT0.0009765625S
MMS 1 Electron Drift Instrument (EDI) Electric Field, Level 2, Burst Survey
2021-04-27T15:38:11Z
Electron Drift Instrument (EDI) Electric Field Burst Survey, Level 2, 0.0009765625 s Data (1024 samples/s). EDI has two scientific data acquisition modes, called electric field mode and ambient mode. In electric field mode, two coded electron beams are emitted such that they return to the detectors after one or more gyrations in the ambient magnetic and electric field. The firing directions and times-of-flight allow the derivation of the drift velocity and electric field. In ambient mode, the electron beams are not used. The detectors with their large geometric factors and their ability to adjust the field of view quickly allow continuous sampling of ambient electrons at a selected pitch angle and fixed but selectable energy. To find the beam directions that will hit the detector, EDI sweeps each beam in the plane perpendicular to B at a fixed angular rate of 0.22 °/ms until a signal has been acquired by the detector. Once signal has been acquired, the beams are swept back and forth to stay on target. Beam detection is not determined from the changes in the count-rates directly, but from the square of the beam counts divided by the background counts from ambient electrons, i.e., from the square of the instantaneous signal-to-noise ratio (SNR). This quantity is computed from data provided by the correlator in the Gun-Detector Electronics that also generates the coding pattern imposed on the outgoing beams. If the squared SNR ratio exceeds a threshold, this is taken as evidence that the beam is returning to the detector. The thresholds for SNR are chosen dependent on background fluxes. They represent a compromise between getting false hits (induced by strong variations in background electron fluxes) and missing true beam hits. The basic software loop that controls EDI operations is executed every 2 ms. As the times when the beams hit their detectors are neither synchronized with the telemetry nor equidistant, EDI data have no fixed time-resolution. Data are reported in telemetry slots. In Survey, using the standard packing mode 0, there are eight telemetry slots per second and Gyn Detector Unit (GDU). The last beam detected during the previous slot will be reported in the current slot. If no beam has been detected, the data quality will be set to zero. In Burst telemetry there are 128 slots per second and GDU. The data in each slot consists of information regarding the beam firing directions (stored in the form of analytic gun deflection voltages), times-of-flight (if successfully measured), quality indicators, time stamps of the beam hits, and some auxiliary correlator-related information. Whenever EDI is not in electron drift mode, it uses its ambient electron mode. The mode has the capability to sample at either 90 degrees pitch angle or at 0/180 degrees (field aligned), or to alternate between 90 degrees and field aligned with selectable dwell times. While all options have been demonstrated during the commissioning phase, only the field aligned mode has been used in the routine operations phase. The choices for energy are 250 eV, 500 eV, and 1 keV. The two detectors, which are facing opposite hemispheres, are looking strictly into opposite directions, so while one detector is looking along B the other is looking antiparallel to B (corresponding to pitch angles of 180 and 0 degrees, respectively). The two detectors switch roles every half spin of the spacecraft as the tip of the magnetic field vector spins outside the field of view of one detector and into the field of view of the other detector. This is the primary data product generated from data collected in electric field mode. The science data generated are drift velocity and electric field data in various coordinate systems. They are derived from triangulation and/or time-of-flight analysis. Where both methods are applicable, their results will be combined using a weighting approach based on their relative errors. The EDI instrument paper can be found at: http://link.springer.com/article/10.1007%2Fs11214-015-0182-7. The EDI instrument data products guide can be found at https://lasp.colorado.edu/mms/sdc/public/datasets/fields/.
J. Burch, R. Torbert, H. Vaith
spase://SMWG/Person/James.L.Burch
PrincipalInvestigator
spase://SMWG/Person/Roy.B.Torbert
PrincipalInvestigator
spase://SMWG/Person/Hans.E.Vaith
PrincipalInvestigator
spase://SMWG/Person/Robert.E.McGuire
MetadataContact
spase://SMWG/Person/Lee.Frost.Bargatze
MetadataContact
The Magnetospheric Multiscale (MMS) Mission home page at Goddard Space Flight Center (GSFC)
https://mms.gsfc.nasa.gov/
The Magnetospheric Multiscale (MMS) Mission Home Page hosted by the Goddard Space Flight Center (GSFC).
Data Caveats and Current Release Notes at LASP MMS SDC
https://lasp.colorado.edu/mms/sdc/public/datasets/fields/
The Magnetospheric Multiscale (MMS) Mission home page hosted by the Laboratory of Atmospheric and Space Physics, Science Data Center (LASP, SDC) at the University of Colorado, Boulder.
At UNH
http://mms-fields.unh.edu/
The Magnetospheric Multiscale (MMS) FIELDS Instrument Suite home page. The web page is hosted by the University of New Hampshire (UNH).
spase://VSPO/NumericalData/MMS/1/FIELDS/EDI/Burst/Level2/ElectricField/PT0.0009765625S
spase://SMWG/Repository/NASA/GSFC/SPDF
Online
Open
FTPS from SPDF (not with most browsers)
ftps://spdf.gsfc.nasa.gov/pub/data/mms/mms1/edi/brst/l2/efield/
In CDF via ftp from SPDF.
HTTPS from SPDF
https://spdf.gsfc.nasa.gov/pub/data/mms/mms1/edi/brst/l2/efield/
In CDF via http from SPDF.
CDAWeb
https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=MMS1_EDI_BRST_L2_EFIELD&index=sp_phys
MMS1_EDI_BRST_L2_EFIELD
Access to ASCII, CDF, and plots via NASA/GSFC CDAWeb
CDF
None
J. Burch, R. Torbert, H. Vaith. Please acknowledge the data providers and CDAWeb when using these data.
spase://SMWG/Repository/NASA/GSFC/SPDF
Online
Open
CDAWeb HAPI Server
https://cdaweb.gsfc.nasa.gov/hapi
MMS1_EDI_BRST_L2_EFIELD
Web Service to this product using the HAPI interface.
CSV
J. Burch, R. Torbert, H. Vaith. Please acknowledge the data providers and CDAWeb when using these data.
Calibrated
spase://SMWG/Instrument/MMS/1/FIELDS/EDI
ElectricField
2015-09-14T14:13:04
-P2M
PT0.0009765625S
Earth.Magnetosheath
Earth.Magnetosphere
Earth.Magnetosphere.Magnetotail
Earth.Magnetosphere.Main
Earth.Magnetosphere.RadiationBelt
Earth.NearSurface.EquatorialRegion
Earth.NearSurface.Plasmasphere
Heliosphere.NearEarth
Epoch Time
Epoch
Epoch Time Tags for Velocity and Electric Field Data, Terrestrial Time 2000 (TT2000)
PT0.0009765625S
ns
1e-9>s
UT
I16
2015-03-01T00:00:00.000000000
2065-12-31T00:00:01.000000000
9999-12-31T23:59:59.999999999
Temporal
Lower-Bound on the Time Tags
Time series defined by using: EPOCH
mms1_edi_t_delta_minus_brst_l2
Lower-Bound on the Epoch Time Tags
PT0.0009765625S
ns
1e-9>s
dt
I10
LinearScale
1707-09-22T12:12:10.961224195
2000-01-01T11:59:00.816000000
9999-12-31T23:59:59.999999999
Temporal
Upper-Bound on the Time Tags
Time series defined by using: EPOCH
mms1_edi_t_delta_plus_brst_l2
Upper-Bound on the Epoch Time Tags
PT0.0009765625S
ns
1e-9>s
dt
I10
LinearScale
1707-09-22T12:12:10.961224195
2000-01-01T11:59:00.816000000
9999-12-31T23:59:59.999999999
Temporal
E x B Drift Velocity Vector (DSL)
Time series defined by using: EPOCH
mms1_edi_vdrift_dsl_brst_l2
E cross B Drift Velocity Vector in Despun Angular Momentum (DSL) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
SC
TimeSeries
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Vector
Velocity
E x B Drift Velocity Vector (GSE)
Time series defined by using: EPOCH
mms1_edi_vdrift_gse_brst_l2
E cross B Drift Velocity Vector in Geocentric Solar Ecliptic (GSE) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
GSE
TimeSeries
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Vector
Velocity
E x B Drift Velocity Vector (GSM)
Time series defined by using: EPOCH
mms1_edi_vdrift_gsm_brst_l2
E cross B Drift Velocity Vector in Geocentric Solar Magnetospheric (GSM) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
GSM
TimeSeries
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Vector
Velocity
Electric Field Vector (DSL)
Time series defined by using: EPOCH
mms1_edi_e_dsl_brst_l2
Electric Field Vector in Despun Angular Momentum (DSL) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
SC
TimeSeries
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Vector
Electric
Electric Field Vector (GSE)
Time series defined by using: EPOCH
mms1_edi_e_gse_brst_l2
Electric Field Vector in Geocentric Solar Ecliptic (GSE) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
GSE
TimeSeries
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Vector
Electric
Electric Field Vector (GSM)
Time series defined by using: EPOCH
mms1_edi_e_gsm_brst_l2
Electric Field Vector in Geocentric Solar Magnetospheric (GSM) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
GSM
TimeSeries
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Vector
Electric
Triangulation Weight
Time series defined by using: EPOCH
mms1_edi_tri_weight_brst_l2
Weighted Use of Triangulation Method in the Level 2 Results
PT0.0009765625S
TimeSeries
TRI weight
I3
LinearScale
0
100
-32768
Other
Triangulation Reduced Chi-Squared
Time series defined by using: EPOCH
mms1_edi_tri_rchisq_brst_l2
Reduced Chi-Squared from Triangulation Analysis
PT0.0009765625S
Reduced chi-squared
F12.4
LinearScale
1.0
500000.0
-1.0e+31
Other
Lower-Bound Drift Velocity Vector Error (DSL)
Time series defined by using: EPOCH
mms1_edi_v_dsl_delta_minus_brst_l2
Lower-Bound on the E cross B Drift Velocity Error in Despun Angular Momentum (DSL) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
SC
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Uncertainty
Velocity
Upper-Bound Drift Velocity Vector Error (DSL)
Time series defined by using: EPOCH
mms1_edi_v_dsl_delta_plus_brst_l2
Upper-Bound on the E cross B Drift Velocity Error in Despun Angular Momentum (DSL) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
SC
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Uncertainty
Velocity
Lower-Bound Drift Velocity Vector Error (GSE)
Time series defined by using: EPOCH
mms1_edi_v_gse_delta_minus_brst_l2
Lower-Bound on the E cross B Drift Velocity Error in Geocentric Solar Ecliptic (GSE) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
GSE
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Uncertainty
Velocity
Upper-Bound Drift Velocity Vector Error (GSE)
Time series defined by using: EPOCH
mms1_edi_v_gse_delta_plus_brst_l2
Upper-Bound on the E cross B Drift Velocity Error in Geocentric Solar Ecliptic (GSE) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
GSE
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Uncertainty
Velocity
Lower-Bound Drift Velocity Vector Error (GSM)
Time series defined by using: EPOCH
mms1_edi_v_gsm_delta_minus_brst_l2
Lower-Bound on the E cross B Drift Velocity Error in Geocentric Solar Magnetospheric (GSM) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
GSM
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Uncertainty
Velocity
Upper-Bound Drift Velocity Vector Error (GSM)
Time series defined by using: EPOCH
mms1_edi_v_gsm_delta_plus_brst_l2
Upper-Bound on the E cross B Drift Velocity Error in Geocentric Solar Magnetospheric (GSM) Cartesian Coordinates
PT0.0009765625S
km/s
1e-3>m/s
Cartesian
GSM
F12.4
LinearScale
3
Vx
1
Vy
2
Vz
3
-500000.0
500000.0
-1.0e+31
Electron
Uncertainty
Velocity
Lower-Bound Electric Field Vector Error (DSL)
Time series defined by using: EPOCH
mms1_edi_e_dsl_delta_minus_brst_l2
Lower-Bound on the Electric Field Vector Error in Despun Angular Momentum (DSL) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
SC
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Uncertainty
Electric
Upper-Bound Electric Field Vector Error (DSL)
Time series defined by using: EPOCH
mms1_edi_e_dsl_delta_plus_brst_l2
Upper-Bound on the Electric Field Vector Error in Despun Angular Momentum (DSL) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
SC
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Uncertainty
Electric
Lower-Bound Electric Field Vector Error (GSE)
Time series defined by using: EPOCH
mms1_edi_e_gse_delta_minus_brst_l2
Lower-Bound on the Electric Field Vector Error in Geocentric Solar Ecliptic (GSE) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
GSE
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Uncertainty
Electric
Upper-Bound Electric Field Vector Error (GSE)
Time series defined by using: EPOCH
mms1_edi_e_gse_delta_plus_brst_l2
Upper-Bound on the Electric Field Vector Error in Geocentric Solar Ecliptic (GSE) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
GSE
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Uncertainty
Electric
Lower-Bound Electric Field Vector Error (GSM)
Time series defined by using: EPOCH
mms1_edi_e_gsm_delta_minus_brst_l2
Lower-Bound on the Electric Field Vector Error in Geocentric Solar Magnetospheric (GSM) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
GSM
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Uncertainty
Electric
Upper-Bound Electric Field Vector Error (GSM)
Time series defined by using: EPOCH
mms1_edi_e_gsm_delta_plus_brst_l2
Upper-Bound on the Electric Field Vector Error in Geocentric Solar Magnetospheric (GSM) Cartesian Coordinates
PT0.0009765625S
mV/m
1e-3>V/m
Cartesian
GSM
F12.4
LinearScale
3
Ex
1
Ey
2
Ez
3
-10000.0
10000.0
-1.0e+31
Uncertainty
Electric