Terapix Star Formation Region IC 1396, © 2002 CFHT
i* mosaics of the COSMOS/ACS field
Data processing steps
by HJMCC - Updated April 20th, 2004

This page describes deep stacks produced at TERAPIX in the COSMOS/ACS F10 field.

Outline of the data processing steps

These images were reduced using the TERAPIX pipeline tools, following standard techniques, which are as follows:

-  Pre-reduced data from CFHT is ingested into the TERAPIX pipeline and used to produce weight-maps for each image

-  We compute a global astrometric and photometric solution for all images (for the i* data there are around 90 images in total)

-  Using this solution, the data is median combined using SWARP to produce a single, contiguous image, as well as its associated weight map.

-  Sextractor is used to produce the final image catalogue from the full contiguous image and its associated weight map

-  A rebinned image (at 0.35''/pixel) is produced for image visualisation purposes

-  Masks are produced which define the usable area of field

-  Star/galaxy separation is carried out using a locally-computed flux-radius to define the stellar locus

-  a second sub-catalogue is produced which contains a subset of parameters extracted from the full catalogue but contains also star/galaxy separation information and mask information.

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