About the verification of the RPW data quality.
RPW L1 QUALITY_BITMASK CDF VARIABLE
Definition
The formal definition of the QUALITY_BITMASK CDF zVariable is provided in the "Metadata Definition for Solar Orbiter Science Data" document (SOL-SGS-TN-0009). There is one value per CDF record.
Table below gives the list of possible values extracted from the rpw_dataset_bitmask_definition_v01.xlsx (in progress). The information provided by this variable will be used by the RPW Calibration Software (RCS) to define the QUALITY_FLAG values (see below).
| Bit | Decimal value | Meaning | Justification | Computation | Comment |
| RPW +Z ANT PA in the line of sight of the HGA during TX ON. | The HGA TX may have an impact on the RPW science measurement quality when the ANT PA in the HGA light of sight | To be determinated by ROC from SPICE computation | |||
| SPICE Heat Shield Door is open | SPICE HSD may have an impact on the RPW +Z ANT bending effect | Known from HSD_SPICE_OPEN E-FECS event | |||
| LFR setting has changed before the end of the current data samples acquisition | According to LFR data acquisition mechanism and CDF structure, it can be impossible for some dataset (i.e., SWF) to take of a LFR setting change - performed via a command execution on-board - in a CDF record time window. Users need nevertheless to be warned when such LFR setting change occurred during a data sample acquisition. | Known from the reception of the TM_LFR_TC_EXE_SUCCESS {YIW00139} S1 TM that confirms the LFR setting change | |||
| Possible SWA-PAS high voltage contamination | SWA-PAS unit may provoke noise on RPW measurements | Inclusion of this event into the bitmask is TBC (quantification of the impact is TBD) | |||
| EMC QUIET window | SolO payload is in EMC QUIET mode | Known from EMC_MAND_QUIET E-FECS event | |||
| EMC NOISY window | SolO payload is in EMC QUIET mode | Known from EMC_PREF_NOISY E-FECS event | |||
| Spacecraft roll manœuvre | Indicate when the spacecraft perform rolls | Known from *_ROLL E-FECS event | |||
| Thruster firings | Indicate when the plateform thruster firings happen | Known from TMC+WOL E-FECS event | |||
| BIAS1_SWEEP - ongoing sweep | Ongoing sweep on one probe. | Should be set from 100 ms before the sweep to 1 s after the sweep on a particular probe. | |||
| BIAS2_SWEEP - ongoing sweep | |||||
| BIAS3_SWEEP - ongoing sweep | |||||
| BIAS1_CURRENT_NONCONSTANT | Changes in biasing current may (1) not be instantaneous, and (2) may have uncertain timestamps. | Should be set from 100 ms before to 1 s after any change in bias current on a particular probe (including sweeps). | |||
| BIAS2_CURRENT_NONCONSTANT | |||||
| BIAS3_CURRENT_NONCONSTANT |
Implementation
The QUALITY_BITMASK values of the RPW L1 CDF will be set by the RPW operations and data pipeline (RODP) hosted at LESIA.
RPW L1R/L2 QUALITY_FLAG CDF VARIABLE
Definition
The formal definition of the QUALITY_FLAG CDF zVariable is provided in the "Metadata Definition for Solar Orbiter Science Data" document (SOL-SGS-TN-0009). There is one value per CDF record.
The possible values of the QUALITY_FLAG CDF zVariable are reported in the following table for convenience.
| Quality | Meaning |
|---|---|
| 0 | Bad data |
| 1 | Known problems, use at your own risk |
| 2 | Survey data, possibly not publication-quality |
| 3 | Good for publication, subject to PI approval |
| 4 | Excellent data which has received special treatment |
Implementation
The QUALITY_FLAG values of the RPW L1 CDF will be all set to "3" by default.
From this initial status, the RCS must then decide in an autonomous way to change or not the value of QUALITY_FLAG records, when transferring the quality information to the output RPW CDF. The RCS decision must rely on relevant data (i.e, QUALITY_BITMASK, other data, parent data, etc.) as explained in the next section.
The RCS cannot increase the value of a given QUALITY_FLAG record. Especially, the higher QUALITY_FLAG index (i.e. "4") is not used for L1/L1R/L2 CDF.
For instance, if a given input RPW L1R CDF has a QUALITY_FLAG record value equals to "2", then the corresponding value in the output L2 CDF can be "2", "1" or "0" depending on the RCS QUALITY_FLAG computation. In another word, "bad quality" data records cannot become "good quality" data records along the L1 to L2 data processing path.
Computation
The detailed computation of the QUALITY_FLAG for each RPW data product is given in the RCS Software Requirements Specification (SRS) documents (see RPW Calibration Software Documentation).
DOCUMENTATION
- The RPW science Data Validation and Verification Plan (DVVP) is available in https://confluence-lesia.obspm.fr/download/attachments/3113240/ROC-GEN-SCI-PLN-00077-LES_Iss01_Rev00%28RPW_DVVP%29.draft-2019011.pdf?version=1&modificationDate=1549625875889&api=v2