Calibration Access and Data Handbook

Combination of the selected observations to make the templates and build CCFs

This step is done mostly interactively and uses some basic ad-hoc IDL procedures, mainly for testing and checking of the consistency of the results.Once the observations have been selected and the count spectra extracted, the available spectra of each background level are accumulated. The combined spectrum is built as follows

Add COUNTS

Average BACKSCAL

Average AREASCAL

Average QUALITY such that QUALITY=0|1

Exposure times are added and the total is written in the EXPOSURE keyword of the header of the output FITS file. Finally, the CCFs are built from these templates.