Raw COS data are processed through the STScI OPUS
pipeline. Data first undergo Generic Conversion, by which bits from individual exposures are unpacked and combined into files containing raw, uncalibrated data. Next, the raw files are processed through the COS calibration pipeline, calcos
, which performs image and spectroscopic reduction to produce output files useful for scientific analysis. Finally, the data are ingested into the Hubble Data Archive through the Data Archive and Distribution System (DADS). This system populates a database containing header keywords that is accessible to users via the Mikulski Archive for Space Telescopes
(MAST). Both calibrated and uncalibrated data are then available for distribution by MAST
to the user.