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1) THEMIS-B: Electric Field 3s and 1/8s Data maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/EFI/PT3S
Start:2007-02-24 00:00:00 Observatory:THEMIS-B Cadence:3 seconds
Stop:2015-05-25 01:02:45 Instrument:THEMIS-B Electric Field Instrument Resource:NumericalData
THEMIS-B Electric Field Instrument (EFI) electric field measurements. This Level 2 product is a 3D estimate of E_perp derived from the spin plane E-field measurements assuming E dot B = 0, using relevant FGM (Flux-Gate Magnetometer) data. Includes spin-averaged, and Fast-survey field data. Spin-averaged (EFS_DOT0) data has approximately 3-second time resolution. Fast-survey (EFF_DOT0) data has 1/8-second time resolution.

2) ARTEMIS P1 field-plasma merged data, near moon maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/ESA.FGM/PT96S
Start:2010-09-01 00:00:00 Observatory:THEMIS-B Cadence:96 seconds
Stop:2015-05-25 01:02:44 Instrument:THEMIS-B Electrostatic Analyzers Resource:NumericalData
This data set contains 96s and 384s resolution magnetic field and plasma ion data from the THEMIS-B ESA and FGM instruments during the near moon (ARTEMIS) phase of the spacecraft life (>~September 1, 2010). The data are at each resolution for several mutually exclusive, contiguous hours during most days. The field-plasma-merged data set was created at GSFC/Space Physics Data Facility (SPDF) as part of the LunaSOX effort, from CDAWeb data sets THB_L2_ESA (good quality, high angular resolution mode only) and THB_L2_FGM. Geocentric spacecraft and moon orbit data from SSCWeb were used to add geocentric and selenocentric spacecraft position data to the merged data set records.

3) THEMIS-B: ESA electron/ion energy fluxes and moments maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/ESA/PT3S
Start:2007-02-16 00:00:00 Observatory:THEMIS-B Cadence:
Stop:2015-05-25 01:02:45 Instrument:THEMIS-B Electrostatic Analyzers Resource:NumericalData
THEMIS-B: Electrostatic Analyzers (ESA): Electron/Ion Ground-Calculated Energy Fluxes (5eV - 25 keV for Ions and 6eV - 30 KeV for Electrons) and Moments (density, velocity, pressure, and temperature). The satellite has 2 modes Fast and Slow survey and 3 data types: FULL, REDUCED and BURST. FULL: 88 angles x 32 energies, time resolution of 128 spins(395 seconds) in slow survey and 32 spins(98 seconds) in fast survey. REDUCED: spin time resolution(3 sec) but angles averaged into 1 angular spectra x 32 energies in slow survey or 6 angular spectra(90 degree x 90 degree window) x 32 energies in fast survey. BURST: 88 angles x 32 energies and spin time resolution(3 sec) but only available sporadically and for short duration. Note that angular resolution affects moments since they are obtained integrating over the mode-specific angular distribution. These moments are processed on the ground. They should be regarded as approximations but will improve in quality as our processing routines are improved over the course of the mission to account for additional sources of variance.

4) THEMIS-B Level 1 Probe State Data maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/Ephemeris/PT01M
Start:2007-02-17 23:35:58 Observatory:THEMIS-B Cadence:01 minutes
Stop:2015-05-25 01:02:42 Instrument:THEMIS-B Probe Status Resource:NumericalData
The L1 STATE files contain the following data, sampled at one-minute intervals: * probe position and velocity in GEI, GSE, and GSM coordinates; * flags to indicate regions of interest and maneuver status; * RA and declination of spin axis; * spin period and spin phase; * spin model parameters for high-precision interpolation of spin phase between one-minute data points. Version number indicates data source as follows: * V00: predicted ephemeris and attitude, no spin period or spin phase; * V01: predicted ephemeris and attitude, spin period and spin phase derived from probe telemetry; * V02: predicted attitude, definitive ephemeris from magnetometer and Doppler tracking data; * V03: corrected attitude and spin phase derived from fully calibrated magnetometer data. (added science attitude determination using perigee data post-processing). Produced by Mission Ops, Science Ops and Science Team.

5) THEMIS-B: Probe Electric Field Instrument and Search Coil Magnetometer Instrument, Digital Fields Board - digitally computed Filter Bank spectra and E12 peak and average in HF band (FBK). maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/FBK/PT4S
Start:2007-02-24 00:00:01 Observatory:THEMIS-B Cadence:4 seconds
Stop:2015-05-25 01:02:42 Instrument:THEMIS-B Electric Field Instrument Resource:NumericalData
The Filter Bank is part of the Digital fields board and provides band-pass filtering for EFI and SCM spectra as well as E12HF peak and average value calculations. The Filter Bank provides band-pass filtering for less computationally and power intensive spectra than the FFT would provide. The process is as follows: Signals are fed to the Filter Bank via a low-pass FIR filter with a cut-off frequency half that of the original signal maximum. The output is passed to the band-pass filters, is differenced from the original signal, then absolute value of the data is taken and averaged. The output from the low-pass filter is also sent to a second FIR filter with 2:1 decimation. This output is then fed back through the system. The process runs through 12 cascades for input at 8,192 samples/s and 13 for input at 16,384 samples/sec (EAC input only), reducing the signal and computing power by a factor 2 at each cascade. At each cascade a set of data is produced at a sampling frequency of 2^n from 2 Hz to the initial sampling frequency (frequency characteristics for each step are shown below in Table 1). The average from the Filter Bank is compressed to 8 bits with a pseudo-logarithmic encoder. The data is stored in sets of six frequency bins at 2.689 kHz, 572 Hz, 144.2 Hz, 36.2 Hz, 9.05 Hz, and 2.26 Hz. The average of the coupled E12HF signal and it's peak value are recorded over 62.5 ms windows (i.e. a 16 Hz sampling rate). Accumulation of values from signal 31.25 ms windows is performed externally. The analog signals fed into the FBK are E12DC and SCM1. Sensor and electronics design provided by UCB (J. W. Bonnell, F. S. Mozer), Digital Fields Board provided by LASP (R. Ergun), Search coil data provided by CETP (A. Roux). Table 1: Frequency Properties. Cascade | Frequency content of Input Signal | Low-pass Filter Cutoff Frequency | Freuency Content of Low-pass Output Signal | Filter Bank Frequency Band 0* 0 - 8 kHz 4 kHz 0 - 4 kHz 4 - 8 kHz 1 0 - 4 kHz 2 kHz 0 - 2 kHz 2 - 4 kHz 2 0 - 2 kHz 1 kHz 0 - 1 kHz 1 - 2 kHz 3 0 - 1 kHz 512 Hz 0 - 512 Hz 512 Hz - 1 kHz 4 0 - 512 Hz 256 Hz 0 - 256 Hz 256 - 512 Hz 5 0 - 256 Hz 128 Hz 0 - 128 Hz 128 - 256 Hz 6 0 - 128 Hz 64 Hz 0 - 64 Hz 64 - 128 Hz 7 0 - 64 Hz 32 Hz 0 - 32 Hz 32 - 64 Hz 8 0 - 32 Hz 16 Hz 0 - 16 Hz 16 - 32 Hz 9 0 - 16 Hz 8 Hz 0 - 8 Hz 8 - 16 Hz 10 0 - 8 Hz 4 Hz 0 - 4 Hz 4 - 8 Hz 11 0 - 4 Hz 2 Hz 0 - 2 Hz 2 - 4 Hz 12 0 - 2 Hz 1 Hz 0 - 1 Hz 1 - 2 Hz *Only available for 16,384 Hz sampling.

6) THEMIS-B: On Board Fast Fourier Transform (FFT) power spectra of Electric (EFI) and Magnetic (SCM) field measurements, for particle and wave burst survey modes. maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/FFT/PT0.0556S
Start:2006-06-26 18:30:23 Observatory:THEMIS-B Cadence:0.0556 seconds
Stop:2015-05-25 01:02:42 Instrument:THEMIS-B Electric Field Instrument Resource:NumericalData
On Board Fast Fourier Transform (FFT) power spectra of Electric (EFI) and Magnetic (SCM) field measurements for particle and wave burst survey modes. Spectra are produced only in Particle Burst and Wave Burst modes; only a preselected four of the signals listed in Table 1 are input at any time. Data fed through the FFT while not in Particle or Wave Burst modes is automatically disgarded. The FFTs (Cooley-Tukey algorithm) are conducted as an integral part of the power spectrum calculation by the Field Programable Gate Arrays (FPGAs). A CORDIC algorithm is used for sine/cosine calculations. The data has raw resolution of 1024 pts for 8,192 sample/sec signals and 2048 pts for 16,384 sample/sec signals (EAC measurements only). Signals at 8,192 samples/sec are handled by 1024-point FFTs, while those at 16,384 samples/sec go through 2048-point FFTs. Past and current signal configurations for specific spacecraft are listed bellow in Table 2. The spectra are arranged into log spaced frequency bins in steps of 16, 32, or 64. Cadence is adjusted to keep packet size constant (i.e. increasing the fequency resolution by a factor of 2 decreases the sampling rate by 1/2). The frequency bins cover a range of 0 Hz to 4 kHz. Table 1: FFT Input Signals. Signal Description SCMX, SCMY, SCMZ: Three axis magnetic fiend from SCM V1 through V6: Probe-spacecraft voltage for all six EFI sensors E12DC, E34DC, E56DC: DC-coupled electric field measured from opposing EFI sensors E12AC, E34AV, E56AC: AC-coupled electric field measured from opposing EFI sensors E12HF: High frequency electric field from EFI Table 2: Spacecraft specific configurations. All probes were initially set to use EDC34, EDC56, SCM2, and SCM3 signals for both particle and wave burst modes. Output was set to 16 frequency bins at 4 Hz. Configuration Changes: 30 June - 3 July 2008: Particle burst spectra on all probes reconfigured to 64 bins at 1 Hz. Table 3: Instrument-Spacecraft Physical Configuration Instrument Alignment in Spacecraft Geometric coordinates (SPG). See THEMIS website for coordinate system details and mechanical drawings. EFI boom 1: Along positive X-axis EFI boom 2: Along negative X-axis EFI boom 3: Along positive Y-axis EFI boom 4: Along negative Y-axis EFI boom 5: Along positive Z-axis EFI boom 6: Along negative Z-axis SCM: *The SCM uses an instrument specific set of axes; an orthogonal system centered instrument with the X-axis 12.1 degrees from the SPG X-axis.

7) THEMIS-B: Fluxgate Magnetometer Measurements 1/128s maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/FGM/PT0.0078125S
Start:2007-02-16 00:00:00 Observatory:THEMIS-B Cadence:
Stop:2015-05-25 01:02:44 Instrument:THEMIS-B Fluxgate Magnetometer Resource:NumericalData
Spacecraft-collected fluxgate magnetometer measurements: Decimated TeleMetry High, DSL, GSE and GSM coordinates, cadence 3s-1/128s. The high-resolution data is available only for time intervals when the instrument was switched into a high-resolution mode. Sensor and electronics design provided by TUBS (Glassmeier, Auster) and IWF (Baumjohann, Magnes)

8) THEMIS-B: On Board spin fits (FIT) of Electric (EFI) and Magnetic (FGM) field. On-Board Spin-fit electric and magnetic field data maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/Fits/PT3S
Start:2008-01-14 17:00:00 Observatory:THEMIS-B Cadence:3 seconds
Stop:2015-05-25 01:02:45 Instrument:THEMIS-B Electric Field Instrument Resource:NumericalData
THEMIS-B: On Board spin fits of Electric (EFI) and Magnetic (FGM) fields. This file contains data EFI and FGM that has been despun on-board to 3 second resolution. It stores meta information like the number of points that contributed to each spin and the standard deviation of those points. For the EFI data it also stores variables with the Z component of the EFI data zeroed and the Z component of the EFI estimated using the E.B=0 equality. The need to use an estimated Z axis for the EFI is due to error in measurements from the EFI axial booms. These data are provided in DSL (despun spacecraft L-Z vector), GSM, and GSE coordinates.

9) THEMIS-B: On Board moments: ESA and SST Electron/Ion moments, density, flux, velocity, pressure and temperature. maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/MOM/PT3S
Start:2007-08-10 00:02:05 Observatory:THEMIS-B Cadence:3 seconds
Stop:2015-05-25 01:02:45 Instrument:THEMIS-B: On Board moments: ESA and SST Electron/Ion moments density, flux, velocity, pressure and temperature. Resource:NumericalData
THEMIS-B On Board moments. On board data outputs include number density, particle flux, energy flux, and a six component symetric momentum flux tensor. Other moments are calculated from these partial moments on the ground adding total pressure, velocity, plasma temperature (measured as a three dimensional energy vector), and a six component symetric pressure tensor to the list of data products. Number density and total pressure are scalar outputs. Velocity is calculated in DSL, GSE, GSM, and MFA coordinates (coordinate descriptions are listed below in Table 1). Magnetic Field Aligned pressure tensor and temperature are calculated as well. All quantities are calculated for both ions and electrons from a combination of ESA and SST data. Moments data are taken at spin resolution in all ESA survey modes except burst. The spacecraft potential, as measure by the EFI, is used to correct for spacecraft charging by shifting the particle energies for calculation; this eliminates contamination from photo-electrons. Also, weighting factors are used to account for instrument specific energy and angle efficiency variations. Table 1: Coordinate Descriptions. Despun Sun - L-vector (DSL): Z-axis points towards the spin axis, the Y-axis is obtained from the cross product of Z and the Spacecraft-Sun direction as viewed from the probe. The X-axis sits in the Z-axis-Sun plane and completes a right handed system. Geocentric Solar Ecliptic (GSE): Z-axis is normal to the solar ecliptic, the X-axis points from earth towards the Sun, and Y complets a right handed system. Geocentric solar Magnetosphereic (GSM): X-axis points from Earth to the Sun, the Y-axis is orthogonal to the Earth's magnetic dipole and points towards the dusk side, and the X-Z plane contains the dipole axis. Magnetic Field Aligned (MFA): Z-axis points along magnetic field lines, the Y-axis is the orthonormal cross product of the Z-axis and a vector pointing towards the Sun, and the X-axis completes the right handed system.

10) THEMIS-B: Search Coil Magnetometer 1/8s, 1/128s and 1/8192s Data maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/SCM/PT0.125S
Start:2007-02-24 00:00:00 Observatory:THEMIS-B Cadence:0.125 seconds
Stop:2015-05-25 01:02:44 Instrument:THEMIS-B: Search Coil Magnetometer Resource:NumericalData
THEMIS-B: Search Coil Magnetometer (SCM) magnetic field measurements. Includes FAST SURVEY, PARTICLE BURST and WAVE BURST data. FAST SURVEY (SCF): 1/8 second time resolution. PARTICLE BURST (SCP): 1/128 second time resolution; only short bursts of data. WAVE BURST (SCW): 1/8192 second time resolution; only short bursts of data. Sensor and electronics design provided by LPP, Roux and Le Contel. SCM Telemetry Modes (Only first 3 apply to level 2 SCM products): +-------------------------------------------------------------------------------------------------------------------------+ | Fast Survey (scf) | Waveform data for the 3 SCM components; sampling rate between 2 and 256 S/s, nominal value is 8. | | Particle Burst (scp) | Waveform data nominally at 128 S/s. | | Wave Burst (scw) | Waveform data nominally at 8192 S/s. | | Filter Bank (fbk)^ | Mean signal value over 6 frequency bands (4-2 kHz, 1-0.5 kHz, 256-128 Hz, 64-32 Hz, 16-8 Hz. | | Particle Burst Spectra (ffp)^^ | Compressed FFT spectra in 16, 32, or 64 frequency bins; sampling between 1/4 to 8 S/s. | | Wave Burst Spectra (ffw)^^ | Compressed FFT spectra in 16, 32, or 64 frequency bins; sampling between 1/4 to 8 S/s. | +-------------------------------------------------------------------------------------------------------------------------+ * ^Only two available inputs between all 3 SCM and 12 EFI data signals. * ^^Only four available inputs between 3 SCM and 16 other data signals.

11) THEMIS-B: Solid State Telescope (SST): Energy flux spectrogram, electron/ion ground-calculated fluxes (30 keV - 300 keV). maxmize
Resource ID:spase://VMO/NumericalData/THEMIS/B/SST/PT3S
Start:2007-03-14 01:00:00 Observatory:THEMIS-B Cadence:3 seconds
Stop:2015-05-25 01:02:44 Instrument:THEMIS-B: Solid State Telescope (SST): Energy flux spectrogram, electron/ion ground-calculated fluxes (30 keV - 300 keV). Resource:NumericalData
THEMIS-B: The Solid State Telescope (SST) measures the incoming intensity (flux per solid angle) of superthermal electrons and ions. The spacecraft is fitted with two units (heads), each SST unit has two pairs of opposing ion and electron sensors. Each single sensor covers an angle of 36 degrees. The units are oriented such that one pair is always centered in the rotation plane, the other oriented at a maximum angle of 54 degrees off the plane. Each pair of units are oriented opposite each other allowing both ion and electron sensors to sweep out a maximum of 92% of the sky (45x45 degree required Elevation by Azimuth FOV, 108x22 raw) . The ion and electron sensors primarily measure particles between 30-300 keV and 30-100 keV respectively with a maximum capability of 20-6000 keV and 25-1000 keV. Full distribution data is measured over 128 angles and 16 energy bins, reduced distribution uses 6 angles and 16 energy bins, and burst mode data has 64 angles in 16 energy bins. Matched and paired electron broom magnets produce quadrapole fields reducing magnetic contamination. A mechanical attenuator is used to increase the instruments dynamical range avoiding oversaturation near the plasma sheet edge.

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