CASSIOPE SPACECRAFT (Swarm-E)
PROCESSED DATA HANDBOOK
IRM Sensor Surface Current (SSC) HDF5 File
The IRM SSC HDF5 file is generated for each IRM turn-on session.
The IRM SSC HDF5 file consists of an IRM Data Group related directly to the IRM SSC data and a Satellite Data Group relating to CASSIOPE location and attitude data.
IRM Attributes:
| Attribute | Definition |
| data_utc_string | Start datetime (UT) for each group of sensor surface current measurements. Each sensor surface current measurement is 1 ms long. |
| detect_count | Number of ions detected on at least one pre-amplifier on the IRM anode |
| hit_count | Number of ions detected on two pre-amplifiers at the same time on the IRM anode |
| manipulated_sensor_surface_current_data | Truth array indicating if any errors were detected and corrected in each set of sensor surface current data |
| measurement_id | Group measurement ID |
| number_samples | Number of sensor surface current samples in each group |
| number_time_of_flight_cycles | Number of time of flight cycles in each IRM measurement group |
| sensor_surface_current | Current on the surface of the IRM instrument (mA). Positive indicates a net positive current flux on the surface (e.g. ions impinging or electrons leaving). |
| temperature | IRM sensor temperature (deg C). |
| vd_negative | Voltage on the negative plate of the outer ion deflection system (V) |
| vd_positive | Voltage on the positive plate of the outer ion deflection system (V) |
| vsa | Voltage on the inner ion deflection dome (V) |
CASSIOPE Atrributes:
| Attribute | Definition |
| geodedic_altitude | Geodetic spacecraft altitude (m) |
| geodedic_latitude | Geodetic spacecraft latitude (deg) |
| geodedic_longitude | Geodetic spacecraft longitude (deg) |
| geographic_x | Geographic cartesian x-component of the satellite position, in the International Terrestrial Reference Frame (m) |
| geographic_y | Geographic cartesian y-component of the satellite position, in the International Terrestrial Reference Frame (m) |
| geographic_z | Geographic cartesian z-component of the satellite position, in the International Terrestrial Reference Frame (m) |
| j2k_vx | X-component of the satellite velocity, in geographic equatorial inertial coordinates (J2000 epoch, m/s) |
| j2k_vy | Y-component of the satellite velocity, in geographic equatorial inertial coordinates (J2000 epoch, m/s) |
| j2k_vz | Z-component of the satellite velocity, in geographic equatorial inertial coordinates (J2000 epoch, m/s) |
| j2k_x | X-component of the satellite position, in geographic equatorial inertial coordinates (J2000 epoch, m) |
| j2k_y | Y-component of the satellite position, in geographic equatorial inertial coordinates (J2000 epoch, m) |
| j2k_z | Z-component of the satellite position, in geographic equatorial inertial coordinates (J2000 epoch, m) |
| local_time | Local time of measurement (h) |
| magnetic_latitude | Magnetic latitude of satellite (IGRF) (deg) |
| magnetic_local_time | MLT (h) = (Magnetic_Longitude – Subsolar_Magnetic_Longitude + 180)/15, with longitudes expressed in degrees |
| magnetic_longitude | Magnetic longitude of satellite (IGRF) (deg) |
| yaw | Satellite attitude yaw angle (deg) |
| pitch | Satellite attitude pitch angle (deg) |
| roll | Satellite attitude roll angle (deg) |
| satellite_eclipse | Eclipse condition of satellite (“Umbra”, “Penumbra”, or” Sunlit”) |
| sun_azimuth | Solar azimuth angle (deg) |
| sun_beta | Solar beta angle (deg) |
| sun_zenith | Solar zenith angle (deg) |
| utc_string | Date and time for each satellite ephemeris data point. String format ‘%Y-%m-%dT%H:%M:%S.%fZ’ (UT) |