South Galactic Cap u-band Sky Survey (SCUSS): Data Reduction

TL;DR

The paper details the data reduction process for the SCUSS u-band survey, including calibration, image stacking, and photometry, and compares its catalog with SDSS and CFHTLS data.

Contribution

It provides a comprehensive description of the data reduction pipeline and calibration procedures for the SCUSS survey, enhancing data quality and usability.

Findings

Survey covers 5000 deg2 with median magnitude of 23.2

Photometry includes multiple measurement methods and calibrations

Comparison shows consistency with SDSS and CFHTLS catalogs

Abstract

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.