ErgSat/Lepe

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Low-Energy Particle Experiments - Electron Analyzer (LEP-e)

Members

  • Principal Investigator
    • Shiang-Yu Wang (Academia Sinica, Taiwan)
  • Project Engineer
    • Yoichi Kazama (Academia Sinica, Taiwan)
  • Project Scientist
    • Sunny W.Y. Tam (National Cheng Kung University, Taiwan)
  • ERG-SC LEP-e POC
    • Tzu-Fang Chang (Nagoya University, Japan & National Cheng Kung University, Taiwan)

Rules of the Road

  • For the general data policy for the ERG satellite, please refer to this webpage.

Specific to LEP-e Data

*Rules of the Road of LEP-e Level 2 data

  • For details of the instrument, please refer to the following article:

Kazama, Y. et al. (2017), Low-energy particle experiments–electron analyzer (LEPe) onboard the Arase spacecraft, Earth, Planets and Space, doi:10.1186/s40623-017-0748-6.

  • Please include the following sentence in Acknowledgements.

"the development and operation of LEP-e is partly funded by Academia Sinica and National Cheng Kung University of Taiwan and also through the support of Ministry of Science and Technology of Taiwan under contract 106-2111-M-001-011 and 105-3111-Y-001-042"

  • Questions, comments, and any feedback relevant to the data should be directed to the LEP-e team (E-mail: erg_lepe_info at isee.nagoya-u.ac.jp).

Updates on the Instrument Status, Data, Calibration, and Notes

  • 20170114
    • N/A

Past articles archived here


Instrument Specifications

Parameter Value Unit Remark
Dimension (upper part) 180DIA x 200H mm
Dimension (lower part) 170D x 180W x 90H mm
Mass 5.512 kg
Power consumption 8.8 W 44V*0.20A, incl. PSU’s efficiency
Raw data production 24.6 kbyte/spin Science data, w/o compression
G-factor (Coarse ch) 9.34e-4 cm^2 sr keV/keV Average, measured
G-factor (Fine ch) 2.15e-4 cm^2 sr keV/keV Average, measured
Energy range ~19 - 19,000 eV @4kV HV
Energy resolution 9.2  % FWHM, measured
Field of views 2.98 x ~270 deg Science data, w/o compression
Angular resolution (Coarse ch) 2.89 x 21.5 deg EL x AZ, FWHM, measured
Angular resolution (Fine ch) 3.05 x 4.71 deg EL x AZ, FWHM, measured

Observation Modes

Observation Mode Changes

Calibration Information

Science Data Products

AA and BB in a data file name represent the major and minor version numbers, respectively, of the data.

Level-2 data

3-D flux data (12 Coarse Channels) (data file name: erg_lepe_l2_3dflux_YYYYMMDD_vAA_BB.cdf)
Name Description Dimension Nominal Time Resolution Data Load Routine for SPEDAS
Epoch Time at the beginning of spin sector (time) 8s erg_load_lepe,datatype='3dflux'
FEDU*3 Unidirectional differential electron number flux (time) x 32(energy) x 12(sensor channel) x 16(spin phase) 8s erg_load_lepe,datatype='3dflux'
FEEDU*3 Unidirectional differential electron energy flux (time) x 32(energy) x 12(sensor channel) x 16(spin phase) 8s erg_load_lepe,datatype='3dflux'
Count_Raw Raw electron count (time) x 32(energy) x 12(sensor channel) x 16(spin phase) 8s erg_load_lepe,datatype='3dflux'
FEDU_Energy minimum and maximum energy*1 of energy bin*2 (time) x 2(min,max) x 32(energy step) 8s erg_load_lepe,datatype='3dflux'
FEDU_Channel The number of sensor channel 12(sensor channel) (constant) erg_load_lepe,datatype='3dflux'
FEDU_Phase The number of spin phase 16(spin phase) (constant) erg_load_lepe,datatype='3dflux'
FEDU_Angle_SGA Detector look-direction in SGA coordinates 2(elevation,azimuth) x 12(sensor channel) (constant) erg_load_lepe,datatype='3dflux'
FEDU_Angle_GSE Detector look-direction in GSE coordinates (time) x 2(elevation,azimuth) x 12(sensor channel) x 16(spin phase) 8s erg_load_lepe,datatype='3dflux'
FEDU_Quality_Index Quality flag for each energy bin and channel (time) x 32(energy) x 12(sensor channel) 8s erg_load_lepe,datatype='3dflux'
Reduct_Flag Flag for reduction of azch/energy/phase/spin (time) 8s erg_load_lepe,datatype='3dflux'
  • *1 E(min) = E(meas) - 0.5 * E(fwhm) ; E(max) = E(meas) + 0.5 * E(fwhm), where E(meas) is measurement energy and E(fwhm) is energy resolution
  • *2 The actual order of energy step is stored in data variable FEDU_Energy. Please refer to it to derive the exact timing of each energy step within a spin phase.
  • *3 { notice about negative flux values } Because of background count subtraction, (energy) fluxes in this CDF may have negative values. Such negative fluxes mean that electron signals are not large compared to background noise, resulting in poor statistical significance. Users must be cautious on analysis with negative values. { end of notice }


Omni-directional flux data (data file name: erg_lepe_l2_omniflux_YYYYMMDD_vAA_BB.cdf)
Name Description Dimension Nominal Time Resolution Data Load Routine for SPEDAS
Epoch Time at the beginning of spin sector (time) 8s erg_load_lepe
FEDO Omni-directional differential electron number flux (time) x 32(energy) 8s erg_load_lepe
FEDO_Energy minimum and maximum energy*1 of energy bin*2 (time) x 2(min,max) x 32(energy step) 8s erg_load_lepe
  • *1 E(min) = E(meas) - 0.5 * E(fwhm) ; E(max) = E(meas) + 0.5 * E(fwhm), where E(meas) is measurement energy and E(fwhm) is energy resolution
  • *2 The actual order of energy step is stored in data variable FEDO_Energy. Please refer to it to derive the exact timing of each energy step within a spin phase.

Data Inventory (Data Archive Status)

Data repository: http://ergsc.isee.nagoya-u.ac.jp/data/ergsc/satellite/erg/lepe/

Name Processed until Latest Calibration Version Remarks
Full/Normal 3D flux 20170301 0.1
OMNI flux 20170331 1.0
Moment TBD TBD Initial calibration in process