PSO processing

Introduction

PSO processing during the mission was mostly related with mission planning and instrument health checks. The mission planning part consisted in the elaboration of the so called long term plan (LTP) and the pre-programmed pointing list (PPL). The PPL was required by MOC to prepare the lists of pointings that were uploaded to the satellite.

The health check consisted in the ingestion of

Long term plan production

The long term plan was updated regularly and as the name indicates it covers long periods of time. In general it was updated to cover

AHF ingestion

The AHF delivered by Flight Dynamics on a daily basis was ingested by the PSO. During the ingestion process, for each PID the planned pointing (PPL) was compared with the actual pointing and any discrepancies larger than a pre defined threshold where flagged and a warning issued. In general this resulted in a clarification request to MOC. Most poniting discrepancies where caused by thruster under or overperformance.

During the ingestion the duration of the PID was also compared against the planned duration as defined in the PPL and the start and end times where also checked. This allowed to the PSO to closely follow any deviation from the pointing law.

Quality Reports ingestion

The data quality reports produced by both DPCs (Daily Quality Report and Weekly Health Report) where ingested daily by the PSO. The reports contained among other things estimates of the noise per pointing period, calibration constants per pointing period, representative temperatures for the subsystems of the two instruments and, in the case of the HFI, glitch rates. The purpose of these reports was three fold:

1. Evaluate status of the mission in terms of sky coverage using pointing information and noise provided in the DQR;
2. Evaluate the general health of the instrument;
3. Provide information that allowed the PSO in the declaration of a small gap

SREM calibrated data analysis

SREM calibrated data is produced by Paul Buehler at the PSI in Zurich and delivered to the PSO on a daily basis. Once the data is delivered, plots showing the calibrated SREM data are then automatically generated. There was a delay of around 48 hours between the data acquisition and the delivery of the data files to the PSO. This prevented this data from being used to raise an alarm during periods of unusually large solar activity (although such warnings where not necessary as both instruments where never at risk of serisou damage from space weather). This data was however used to correlate with HFI glitches and temperature fluctuations in the 100mK stage.