4.4.9 XRCF Calibration Data Management

Lab sub-assembly and XRCF calibration activities have produced Terabytes of data. Data from the XRCF and on-orbit data arrive in telemetry format and will be converted by the ASC into its standard archival format for archiving. Ancillary data from the XRCF environmental instrumentation and the test data from the HRMA X-ray Data System (HXDS) will also be archived by the ASC. They intend to archive both raw data and processed data.

At XRCF two parallel data paths were employed. Both ACIS-2C and the flight instrument had raw CCD pixel data available through a port called the High Speed Tap (HST). These data are similar to the sub-assembly calibration data, and form a direct check on the flight telemetry format data. The HST also offered a much higher bandwidth data path valuable during ground calibration. The HST will not be available during flight. All ACIS-2C data were collected through the HST, because the ACIS on-board processors were not present. HST data were collected and archived by the ACIS EGSE. Copies of the raw data were made on DLT tapes by the ACIS team, and one copy resides at PSU and one at MIT. An additional copy was made by Bruce Wyshak of the ASC, and the DLT tapes for this copy reside at the ASC. Standardly processed data were forwarded by the ACIS EGSE via ftp to a mirror site at the XRCF third floor data system. Copies of the processed data on DLT and DAT tape are also maintained at PSU and MIT.

The second data path was the normal flight telemetry, processed as science and engineering data packets and sent to the RCTUE. Data from the RCTUE were collected and archived by the MCC. Telemetry format data from the flight instrument were processed by the AQLC computer. These data have also been archived and supplied to the ASC.