ELectron Spectrometer (ELS) Information

ELectron Spectrometer (ELS) Information

Last Updated: April 18, 2006 by Sandee Jeffers

ELS

Document References:

ASPERA-3 Proposal, Part I: Scientific and Technical Plan, ~865 kb, 50 pages
ELS IDFS Design Document, ~484 kb, 212 pages
ELS-DPU Dataflow/Interface, ~1.2 Mb, 12 pages
ELS Calibration Report, ~2.5 Mb, 37 pages

General Information:

Energy Range: 1 eV - 20 keV
Energy Resolution, DE/E: 8%
Possible Number Energy Steps: 512
- Two Ranges (Low, High) with 128 Steps Each
- 32 Returned
Number Anodes: 16
Acceptance Angle: 360 deg x 2.2 deg
Angular Resolution: 22.5 deg
Geometric Factor (22.5 deg): 5.77 x 10^-4 cm² sr
Geometric Factor x DE/E (22.5 deg): 4.75 x 10^-5 cm² sr eV/eV
Sweep Time: 1 Sweep Every 4 sec
Raw Bit Rate: 8 kbps

There are 6 Virtual Instruments for the Electron Spectrometer:

2 Science Data
1. ELS Science Low Data of 16 anodes:
  - 128 steps
  - 16 bits per sample
  - 31.25 msec for sampling full sweep
  - IDFS Name: ELSSCIL for ELS SCIence Low data
2. ELS Science High Data of 16 anodes:
  - 128 steps
  - 16 bits per sample
  - 31.25 msec for sampling full sweep
  - IDFS Name: ELSSCIH for ELS SCIence High data
2 Sweep Data
1. ELS Sweep Low Data of 2 Sensors (1 Deflection Voltage Reference and 1 Deflection Voltage Monitor) for each Step:
  - 128 steps
  - 16 bits per sample
  - 31.25 msec for sampling full sweep of 128 steps
    28.125 msec. data accumulation + 3.125 msec. data latency
  - IDFS Name: ELSSWPL for ELS SWeeP Low data
2. ELS Sweep High Data of 2 Sensors (1 Deflection Voltage Reference and 1 Deflection Voltage Monitor) for each Step:
  - 128 steps
  - 16 bits per sample
  - 31.25 msec for sampling full sweep of 128 steps
    28.125 msec. data accumulation + 3.125 msec. data latency
  - IDFS Name: ELSSWPH for ELS SWeeP High data
2 Engineering Data (Health & Safety, Monitors, Voltages)
1. 5 Engineering Monitor and Reference Values:
  - 8 bits per sample
  - data samples taken every 31.25 msec.
  - IDFS Name: ELSENG8 for ELS ENGineering 8-bit monitors
2. 6 Engineering Status Indicators:
  - 1 bit per sample
  - data samples taken every 31.25 msec.
  - IDFS Name: ELSENGS for ELS ENGineering Status indicators