  The South Galactic Cap u-band Sky Survey (SCUSS) is a deep u-band imaging
survey in the Southern Galactic Cap, using the 90Prime wide-field imager on the
2.3m Bok telescope at Kitt Peak. The survey observations started in 2010 and
ended in 2013. The final survey area is about 5000 deg2 with a median 5-sigma
point source limiting magnitude of about 23.2. This paper describes the survey
data reduction process, which includes basic imaging processing, astrometric
and photometric calibrations, image stacking, and photometric measurements.
Survey photometry is performed on objects detected both on SCUSS u-band images
and in the SDSS database. Automatic, aperture, point-spread function (PSF), and
model magnitudes are measured on stacked images. Co-added aperture, PSF, and
model magnitudes are derived from measurements on single-epoch images. We also
present comparisons of the SCUSS photometric catalog with those of the SDSS and
CFHTLS.
