CAA Operational Review 9 Double Star PEACE Team Report A.N. Fazakerley, B. Mihaljcic, N. Doss, C. Annekallu, Y. Bogdanova, G. Watson. MSSL-UCL Operational Review Meeting – 9 ESAC 04 June 2014

Personnel No formal funding for Double Star archiving activities Same team as for Cluster archiving work, but Branislav has done the vast majority of the Double Star work in recent times

Summary Delivery of PITCH_SPIN data for both spacecraft for all years Preparation of Caveats dataset Significant efforts to optimise quality of delivered data, overcoming challenges of noisy and/or incomplete raw data

Status of software development (1) Production Software – PITCH_SPIN PITCH_SPIN CAA data is produced twice, once for each raw dataset Merging software picks the best data spin-by-spin to produce final file (using G version unless the other is better) 7 types of problem (usually due to poor raw data quality) identified and handled The following slides illustrate these points Status of software development (1)

PITCH_SPIN production process 3DF data (O version, IDFS) Ground made PAD (O version, IDFS) 3DF data (G version, IDFS) Ground made PAD ( version, IDFS) CAA Format Data 2004-08-19 (232) CAA PITCH_SPIN data ‘O’ version data ‘G’ version Merged data (spin-by-spin) Spin Origin (G or O) Corrections may be needed at any of these stages Successful PITCH_SPIN production implies that 3DF data problems have also been solved

Merging of CAA files produced from “O” and from “G” version of raw data at spin level CAA PITCH_SPIN data [‘O version’] CAA PITCH_SPIN data [‘G version’] CAA PITCH_SPIN data (produced by taking best spins from either ‘O’ or ‘G’ version) The merging code can handle, missing, incomplete and shifted spins if they occur in any of the datasets then choose the best one for the final CEF file.

Correction of PITCH_SPIN production errors BEFORE: TC-1 PITCH_SPIN CAA format Data AFTER: TC-1 PITCH_SPIN CAA format Data PITCH_SPIN data PITCH_SPIN data The DS or DS_rp IDFS 3DF data had no problems. PITCH_SPIN data plots (LHS plot), had problems below ~700 eV as RPAD had problems REASON: For such cases the RPAD production code was missing the start or end timestamp due to a corrupt data stream. We fixed the problem and regenerated DS and DS_rp RPAD to make correct PITCH_SPIN (RHS plot)

Correction of PITCH_SPIN production errors : TC-2 preset problem in raw 3D data (aa mode) 2004-08-19 (232) Corrected 3DF data O version 3DF data G version 3DF data O version 3DF data G version

Correction of PITCH_SPIN production errors In this case the CAA production code can be adjusted to make a good CAA CEF file The recipe file that the CAA code makes ensures that in this case spins only from fixed DS data is used to make final CAA file (here version ‘M’) PITCH_SPIN data ‘O’ version (low and high energy sweep preset FIXED 100%) PITCH_SPIN data ‘G’ version (only low energy sweep could be FIXED 100%) PITCH_SPIN Merged data (The merged data set is 100% FIXED) Spin Origin 2004-08-20 (233)

2004-08-21 (234) Correction of PITCH_SPIN production errors In this case only the O ver high energy sweep is ok (see panel 1) and only the low energy sweep from G ver is ok (see panel 2) The CAA production code can be adjusted to take only : O ver: high energy sweep from panel 1 G ver: low energy sweep from panel 2 to make the final CAA file shown in panel 3 Hence data from alternate files is taken as shown in panel 4 PITCH_SPIN data ‘O’ version (only HIGH energy sweep could be FIXED 100%) PITCH_SPIN data ‘G’ version (only LOW energy sweep could be FIXED 100%) PITCH_SPIN Merged data (The merged data set is 100% FIXED) Spin Origin 2004-08-21 (234)

2004-08-20 (241) Correction of PITCH_SPIN production errors In this case only the DS data is used to make the correct CAA CEF for a case when there are data gaps. PITCH_SPIN data ‘O’ version (HIGH and LOW sweeps 100% FIXED) PITCH_SPIN data ‘G’ version (LOW sweeps 100% FIXED) PITCH_SPIN Merged data Spin Origin 2004-08-20 (241)

Example of delivered PITCH_SPIN data with multiple gaps due to gaps in raw data CAVEATS and possibly Status flags will inform the user that these are “real” data gaps that cannot be fixed.

Status of software development (2) Production Software – 3DX 3DX CAA production code complete, merging software ready Production Software – SCPOT Algorithm available, may try to improve; specific CAA production code tbd Production Software – Moments production software exists, merging software to be produced, accuracy will be affected when no spacecraft potential estimate can be produced Production Software – Caveats production software exists, may update to indicate days with multiple gaps (Limited progess on Status parameters) Status of software development (2)

Status of calibration and cross-calibration activity It is difficult to perform in-flight cross-calibration for the PEACE instruments on the Double Star spacecraft. There is no direct measurement of spacecraft potential, so determination of PEACE moments is only possible if one may estimate the spacecraft potential from PEACE spectra (i.e. if the energy range covered the photoelectrons). Even when PEACE moments can be produced, there is a problem because there is no absolute density reference (such as is provided by WHISPER on Cluster) – HIA on TC-1 is not suitable, nor LEID on TC-2. There are no convenient close conjunctions with other spacecraft that might provide a useful reference either.

Data delivery status TC-1 UPDATED since the written report 2 weeks ago   TC-1 UPDATED since the written report 2 weeks ago (data not delivered where JPEG compression mode was not used - rare) TC2 UPDATED since the written report 2 weeks ago Data delivery status Product name 2004 2005 2006 2007 2008 MOMENTS   n/a PITCH_SPIN D 3DX 3DX-LAR (rare) SCPOT Product name 2004 2005 2006 2007 2008 MOMENTS   PITCH_SPIN D 3DX 3DX-LAR (rare) SCPOT

Data delivery plan Logical Sequence (timing tbc) 3DX and 3DX-LAR data   Logical Sequence (timing tbc) 3DX and 3DX-LAR data following merging software provision (note the files are so large that they must be delivered in 2 hour parts, so production/delivery may be time consuming) SC_POT following completion of production code Moments production code exists but importantly we need to ensure the quality flag highlights intervals where SC_POT is unavailable (lack of potential is less important for plasmasheet than for solar wind/magnetosheath) Caveats following completion of data gap warning code based on existing software that estimates number of gaps per day, may also indicate days lacking estimated spacecraft potential data Data delivery plan

Estimating spacecraft potential from PEACE data (suitable energy spectra) TC1 (2007-072) 3DF 05:00-06:00 electrons Plasma electrons Photo Automated software s/c potential estimate Clear distinction between the photo-electron and plasma electron populations Spacecraft potential (black line) can be estimated from PEACE data. We don’t claim this estimate is perfect! In this case relatively accurate MOMENTS can be produced.

Estimating spacecraft potential from PEACE data (unsuitable energy spectra) TC1 (2007-093) 3DF 13:00-14:00 electrons Plasma Electrons? Photo In this case there is only the plasma electron population, but no photo-electron population Hence, no s/c potential estimate can be made from PEACE energy spectra. Moments accuracy is reduced Last of potential data less serious when plasma is at high energies, e.g plasmasheet .

Data re-delivery plan Aspirations (timing tbc) PITCH_SPIN data   Aspirations (timing tbc) PITCH_SPIN data possibly we will regenerate using new CAA FGM dataset (present version uses TC-1 spin rate FGM data and TC-2 FGM CoI FGM data) All datasets possibility of regeneration if calibration knowledge is improved Data re-delivery plan

Documentation The CAA has these documents: User Guide to the PEACE measurements in the CAA – in draft form Calibration Report of the PEACE measurements – not available Interface Control Document for DS PEACE in the CAA V3.0 The PEACE team CAA-related papers:  Paper on Double Star calibrations in preparation The CAA Documentation page does not (but could) provide a link to the PEACE Operations History webpages. Documentation

Replies to OR8 (and earlier) Recommendations OR4- R18 to all teams and CAA: Double Star, the first bilateral mission between ESA and China, ceased collecting data in 2008, and the existing data currently resides with the individual instrument teams in Europe and China. Without proper archiving of the Double Star data it will eventually be lost to the scientific community as has happened many times in the past with previous space missions. The board is aware that activities to ingest Double Star data into the CAA have begun, as recommended in OR3. However, the board fears that in the absence of additional funds for the CAA to complete this work, this important activity will fail. The quality of the data ingested cannot be guaranteed without proper investment in calibration and data validation activities. Without extra funding, some of the instrument teams will be unable to provide their data to the CAA. The board urges that the CAA seek additional support to continue quality assurance and archiving of the Double Star data PROPOSE TO CLOSE No extra funding has been made available. Nevertheless, we have reached the stage of beginning data deliveries.

Replies to CC19 Recommendations CC19-AI-01 to All: Check that the headers are complete and correct. This concerns particularly various descriptions in different levels (experiment, instrument, dataset). PROPOSE TO CLOSE The experiment/instrument/dataset description headers for Double Star have been checked and updated where necessary. The main change was to update email addresses. Updated headers have been submitted to CAA   CC19-AI-07 to PEACE: to provide the DWP team with a source code of the software required to read PEACE HK data (both CLUSTER and DOUBLE STAR) We have provided the required software and DWP have confirmed that it was effective. CC19-AI-17: to deliver the annual report and ICD on the Double Star datasets for the OR-9 review This document is the annual report. The ICD was not updated.

Replies to CC19 Recommendations CC19-AI-18: to deliver the Double Star datasets of 2004-8 to the CAA. IN PROGRESS UPDATED since the written report 2 weeks ago PITCH_SPIN has been delivered for all years for both spacecraft. More datasets will follow.   CC19-AI-21: to investigate if their processed data and PP are shifted in time in 20-22 Sep 2006 and 1-30 Nov 2006 PROPOSE TO CLOSE This has been investigated and no such time shift has been observed in PEACE data.

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